U.S. patent application number 11/096103 was filed with the patent office on 2005-08-04 for device and method for supplying power to a vehicle, semi-conductor circuit device for use in the same and collective wiring device for a vehicle or an automobile.
This patent application is currently assigned to Hitachi, Ltd.. Invention is credited to Horibe, Kiyoshi, Koni, Mitsuru, Saito, Hiroyuki, Sakamoto, Shinichi, Yoshida, Tatsuya.
Application Number | 20050168072 11/096103 |
Document ID | / |
Family ID | 27054732 |
Filed Date | 2005-08-04 |
United States Patent
Application |
20050168072 |
Kind Code |
A1 |
Saito, Hiroyuki ; et
al. |
August 4, 2005 |
Device and method for supplying power to a vehicle, semi-conductor
circuit device for use in the same and collective wiring device for
a vehicle or an automobile
Abstract
A power supply line is wired in a loop from a battery power
supply, and a power supply relay circuit is installed
intermediately of the power supply line such that power is supplied
from the power supply relay circuit to an electric load connected
to a terminal unit of an intensive wiring line. By this
arrangement, not only wires for control signals but also wires for
power supply can be reduced. The terminal unit may serve also as
the power supply relay circuit.
Inventors: |
Saito, Hiroyuki;
(Hitachinaka-shi, JP) ; Yoshida, Tatsuya;
(Naka-gun, JP) ; Sakamoto, Shinichi; (Mito-shi,
JP) ; Koni, Mitsuru; (Hitachinaka-shi, JP) ;
Horibe, Kiyoshi; (Hitachi-shi, JP) |
Correspondence
Address: |
CROWELL & MORING LLP
INTELLECTUAL PROPERTY GROUP
P.O. BOX 14300
WASHINGTON
DC
20044-4300
US
|
Assignee: |
Hitachi, Ltd.
Chiyoda-ku
JP
Hitachi Car Engineering Co., Ltd.
Hitachinaka-shi
JP
|
Family ID: |
27054732 |
Appl. No.: |
11/096103 |
Filed: |
April 1, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11096103 |
Apr 1, 2005 |
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10131248 |
Apr 25, 2002 |
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10131248 |
Apr 25, 2002 |
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09504116 |
Feb 15, 2000 |
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6401891 |
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09504116 |
Feb 15, 2000 |
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08894285 |
Aug 21, 1997 |
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6182807 |
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Current U.S.
Class: |
307/10.1 |
Current CPC
Class: |
B60R 2016/0322 20130101;
B60G 17/0195 20130101; B60L 1/00 20130101; B60G 2600/08 20130101;
B60R 16/0315 20130101; B60G 17/0185 20130101; B60R 2021/01061
20130101; B60R 2021/0104 20130101; F16F 15/02 20130101; B60R
2021/01115 20130101 |
Class at
Publication: |
307/010.1 |
International
Class: |
B60L 009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 1995 |
JP |
7-32647 |
Sep 15, 1995 |
JP |
7-228238 |
Claims
1. A power supplying apparatus for an automobile, comprising: an
anti-lock braking control unit including a control circuit for
controlling a solenoid for a hydraulically controlled valve of an
anti-lock braking apparatus of said automobile; a power supply line
for connecting said control unit and a power supply of said vehicle
to each other; and an anti-lock braking apparatus power supply
circuit for connecting or disconnecting said power supply line
connected to said anti-lock braking control unit to or from said
solenoid.
Description
TECHNICAL FIELD
[0001] This invention relates to a power supplying apparatus and
method for a plurality of electric loads remote from a power
supply, and also to a semiconductor circuit apparatus and an
intensive wiring apparatus for transmission of control information
for use with the power supplying apparatus and method.
BACKGROUND ART
[0002] In a conventional power supplying apparatus for a vehicle, a
power supply carried on the vehicle and each of several electric
loads are connected to each other by a long power supply line with
a fuse interposed therein. When a power supply line is
short-circuited, the fuse is blown to disconnect the electric load
from the power supply.
[0003] In control of electric loads of a conventional vehicle, a
so-called multiplexing wiring system is known wherein controllers
for individually controlling a plurality of electric loads are
integrated into a smaller number of controllers having a
communication function and a calculation function so that control
signals for the electric loads are calculated by the smaller number
of controllers and the control signals are transmitted to terminal
equipments connected by communication lines to control several
electric loads connected to each of the terminal equipments (refer
to, for example, U.S. Pat. Nos. 4,771,382, 5,113,410, 4,855,896 and
5,438,506).
[0004] However, power supply lines are usually wired from a power
supply directly to individual electric loads or to driving circuits
for the electric loads, and the number of power supply lines is
equal to or larger than the number of electric loads and the floor
or the inside of the body of a vehicle is full of wiring lines.
[0005] Accordingly, basically it is a principle object of the
present invention to provide a novel power supplying apparatus for
a vehicle. More specifically, it is an object of the present
invention to reduce power supply lines of a power supplying
apparatus for a vehicle. It is another object of the present
invention to eliminate a fuse. It is a further object of the
present invention to provide a novel power supplying method. It is
a still further object of the present invention to provide a novel
semiconductor circuit apparatus for use for supplying power. It is
a yet further object of the present invention to provide a novel
intensive wiring apparatus integrated with a power supply control
system. It is a yet further object of the present invention to
provide a novel power supplying apparatus for a particular electric
load of an automobile. It is a yet further object of the present
invention to provide a novel apparatus for detecting
short-circuiting of a power supply line. The objects recited above
are solved by different solving means disclosed hereinbelow or in
the appended claims.
DISCLOSURE OF INVENTION
[0006] According to a first aspect of the present invention, since
two power supply lines are led out from one of poles of a power
supply such that power can be supplied from both of the power
supply lines to electric loads, a novel power supplying apparatus
wherein, even if one of the lines is short-circuited, supply of
power can be maintained from the other line can be provided.
[0007] According to another aspect of the present invention, since
an electric switching apparatus for controlling connection and
disconnection between a power supply line and an electric load is
provided in a relay circuit provided between the power supply line
and the electric line such that, when the power supply line is
short-circuited, the switching apparatus is operated to disconnect
the electric load from the circuit, a fuse can be eliminated.
[0008] According to a further aspect of the present invention,
since power transmission lines of a closed loop are formed from
power supply lines connected to one of two poles of a power supply
such that power can be supplied from the opposite sides of a
connection point of an electric load so that, even if
short-circuiting or disconnection occurs with one of the
transmission lines, supply of power can be continued from the other
side of the transmission line, the number of electric loads which
are rendered uncontrollable by a failure of a transmission line can
be reduced.
[0009] According to a still further aspect of the present
invention, since a network is formed from power supply lines
similar to communication lines to construct a multiplexing wiring
system which can handle both of control signals and power, also the
power supply lines are aggregated and the number of electric wires
can be reduced.
[0010] According to a yet further aspect of the present invention,
since power supplying apparatus for electric loads for an air
conditioner control unit, a power train control unit, a lamp
control unit, a navigation unit, an anti-lock braking control unit,
a window opening and closing motor control unit, a display circuit
control unit for an instrument panel, a rear defogger controlling
unit, a beacon control unit and so forth are formed from a novel
power supplying apparatus of the present invention, those electric
loads in an automobile can be controlled with a reduced number of
wiring lines.
BRIEF DESCRIPTION OF DRAWINGS
[0011] FIG. 1 is a view of an entire power supplying system for an
automobile to which the present invention is applied;
[0012] FIG. 2 is a functional block diagram of the power supplying
system;
[0013] FIG. 3 is a diagram illustrating operation of the power
supplying system;
[0014] FIG. 4 is a state transition table of the operation of the
power supplying system;
[0015] FIG. 5 is a view showing an appearance of a power supply
wire for supplying power according to the present invention;
[0016] FIG. 6 is a functional block diagram of a BCM;
[0017] FIG. 7 is a circuit diagram of a trouble detection circuit
for an electric wire;
[0018] FIG. 8 is a diagrammatic view showing a construction of a
switching circuit;
[0019] FIG. 9 is a diagram illustrating operation for power supply
switching;
[0020] FIG. 10 is a diagram showing a construction of a power
supply circuit;
[0021] FIG. 11 is a diagram showing a construction of an
interruption circuit;
[0022] FIG. 12 is a detailed circuit diagram of an output
interface;
[0023] FIG. 13 is a detailed circuit diagram of an input
interface;
[0024] FIG. 14 is a functional block diagram of an FIM;
[0025] FIG. 15 is a functional block diagram of a DDM;
[0026] FIG. 16 is a diagram showing a construction of another power
supply circuit;
[0027] FIG. 17 is a functional block diagram of a PDM, an RRDM and
an RLDM;
[0028] FIG. 18 is a functional block diagram of an IPM;
[0029] FIG. 19 is a functional block diagram of an RIM;
[0030] FIG. 20 is a functional block diagram of a DSM and a
PSM;
[0031] FIG. 21 is a view illustrating an extension connector;
[0032] FIG. 22 is a view illustrating a T-shaped branching
connector;
[0033] FIG. 23 is a diagram illustrating a power supply module for
extension;
[0034] FIG. 24 is a drawing showing input data tables of individual
units;
[0035] FIG. 25 is a drawing showing output data transmission)
tables of the individual units;
[0036] FIG. 26 is a drawing showing output data tables for an ABS,
an SDM, an air conditioner control unit, a PCM and a navigation
unit;
[0037] FIG. 27 is a flow chart illustrating operation of a power
supply network after connection to a battery;
[0038] FIG. 28 is a flow chart of diagnosprocesses;
[0039] FIG. 29 is a flow chart of transmission signal interrupt
processing;
[0040] FIG. 30 is a flow chart of fixed interrupt processing;
[0041] FIG. 31 is a flow chart of data transmission processing;
[0042] FIG. 32 is a flow chart of trouble detection for a
integnated power/communication cable;
[0043] FIG. 33 is a flow chart of trouble detection for a switching
element;
[0044] FIG. 34 illustrates trouble detection of a driven load;
[0045] FIG. 35 is a control flow chart of a power window;
[0046] FIG. 36 is a control flow chart of a turn signal lamp;
[0047] FIG. 37 is a control flow chart of a headerlamp;
[0048] FIG. 38 is a control flow chart of a brake lamp;
[0049] FIG. 39 is a control flow chart of a door lock;
[0050] FIG. 40 is a control flow chart of a power seat;
[0051] FIG. 41 is a control flow chart of trunk opening
control;
[0052] FIG. 42 is a circuit diagram showing a construction of an
I/O communication IC;
[0053] FIG. 43 is a diagram illustrating transmission data
formats;
[0054] FIG. 44 is a state transition table of the communication
IC;
[0055] FIG. 45 is a time chart of a communication bus;
[0056] FIG. 46 is a diagram illustrating a data communication
circuit;
[0057] FIG. 47 is a time chart of a transmission circuit;
[0058] FIG. 48 is a drawing showing a circuit construction of a
schedule counter;
[0059] FIG. 49 is a time chart of the schedule counter;
[0060] FIG. 50 is a drawing showing a circuit construction of a VPW
generator;
[0061] FIG. 51 is a time chart of the VPW generator;
[0062] FIG. 52 is a drawing showing a circuit construction of a
signal generation ROM;
[0063] FIG. 53 is a drawing showing a circuit construction of a CRC
generator;
[0064] FIG. 54 is a diagram showing a construction of a data
receive circuit;
[0065] FIG. 55 is a time chart of the data receive circuit;
[0066] FIG. 56 is a drawing showing a circuit construction of a VPW
decoder;
[0067] FIG. 57 is a time chart of the VPW decoder;
[0068] FIG. 58 is a drawing showing a circuit construction of a CRC
checker;
[0069] FIG. 59 is a drawing showing a circuit construction of a
clock generator;
[0070] FIG. 60 is a time chart of the clock generator;
[0071] FIG. 61 is a diagram showing a system configration of a
PCM;
[0072] FIG. 62 is a detailed diagram illustrating an internal
configration of the PCM;
[0073] FIG. 63 is a drawing showing a detailed configration of an
output interface;
[0074] FIG. 64 is a drawing showing a detailed configration of
another output interface;
[0075] FIG. 65 is a detailed diagram illustrating a digital input
interface;
[0076] FIG. 66 is a drawing showing a connection condition of IPM
loads;
[0077] FIG. 67 is a drawing showing a connection condition of RIM
loads;
[0078] FIG. 68 is a diagram of a conventional system configration
of a PCM;
[0079] FIG. 69 is a basic control flow chart of the PCM;
[0080] FIG. 70 is a flow chart of analog signal input
processing;
[0081] FIG. 71 is a flow chart of engine speed measurement
processing;
[0082] FIG. 72 is a flow chart of initialization processing in the
basic control flow chart;
[0083] FIG. 73 is a flow chart of engine control processing in the
basic control flow chart;
[0084] FIG. 74 is a flow chart of AT control processing in the
basic control flow chart;
[0085] FIG. 75 is a detailed flow chart of power supply cut-off
processing upon short-circuiting in the basic control flow
chart;
[0086] FIG. 76 illustrates power supply cut-off processing upon
load grounding in the basic control flow chart;
[0087] FIG. 77 is a detailed flow chart of transmission data write
processing in the basic control flow chart;
[0088] FIG. 78 is a detailed flow chart of ending processing in the
basic control flow chart;
[0089] FIG. 79 is a flow chart of multiplexed communication data
receive processing;
[0090] FIG. 80 is a diagram showing a system configuration of an
SDM;
[0091] FIG. 81 is a detailed diagram illustrating an internal
configuration of an SDM module;
[0092] FIG. 82 is a drawing showing a load connection state of a
BCM and an IPM;
[0093] FIG. 83 is a drawing showing a conventional construction of
an SDM system;
[0094] FIG. 84 is a drawing showing a basic control flow chart of
an SDM of the present embodiment;
[0095] FIG. 85 is a flow chart of air bag control processing in the
basic control flow chart;
[0096] FIG. 86 is a flow chart of transmission data write
processing in the basic control flow chart;
[0097] FIG. 87 is a flow chart of multiplexed communication data
receive processing;
[0098] FIG. 88 is a diagram showing a system configuration of an
A/C control unit;
[0099] FIG. 89 is a detailed diagram illustrating an internal
configuration of the A/C control unit;
[0100] FIG. 90 is a drawing showing a detailed configuration of an
output interface;
[0101] FIG. 91 is a drawing showing a load connection state of an
IPM;
[0102] FIG. 92 is a diagram showing a system configuration of a
conventional A/C control unit;
[0103] FIG. 93 is a basic control flow chart of the A/C control
unit of the present embodiment;
[0104] FIG. 94 is a flow chart of analog signal input
processing;
[0105] FIG. 95 is a flow chart of A/C control processing in the
basic control flow;
[0106] FIG. 96 is a flow chart of door opening setting processing
of the A/C control processing;
[0107] FIG. 97 is a flow chart of blower fan capacity setting
processing of the A/C control processing;
[0108] FIG. 98 is a control flow chart of power supply cut-off
processing of the A/C control processing;
[0109] FIG. 99 is a flow chart of transmission data write
processing in the basic control flow chart;
[0110] FIG. 100 is a flow chart of multiplexed data receive
processing in the basic control flow chart;
[0111] FIG. 101 is a diagram showing a system configuration of an
ABS system;
[0112] FIG. 102 is a detailed diagram showing an internal
configuration of an ABS module;
[0113] FIG. 103 is a drawing illustrating a load connection
situation of an FIM;
[0114] FIG. 104 is a drawing showing a load connection situation of
an IPM;
[0115] FIG. 105 is a drawing showing a conventional construction of
an ABS system;
[0116] FIG. 106 is a basic control flow chart of an ABS of the
present embodiment;
[0117] FIG. 107 is a flow chart of wheel speed calculation
processing;
[0118] FIG. 108 is a flow chart of brake control processing in the
basic control flow chart;
[0119] FIG. 109 is a flow chart of transmission data write
processing in the basic control flow chart;
[0120] FIG. 110 is a flow chart of multiplexed communication data
receive processing in the basic control flow chart;
[0121] FIG. 111 is a diagram showing a system configuration of a
navigation system;
[0122] FIG. 112 is a detailed diagram showing an internal
configuration of the navigation system;
[0123] FIG. 113(A) is a diagram illustrating a load connection
situation of an IPM;
[0124] FIG. 113(B) is a diagram illustrating a load connection
situation of a BCM;
[0125] FIG. 114 is a drawing showing a conventional example of a
navigation system;
[0126] FIG. 115 is a basic control flow chart of a navigator;
[0127] FIG. 116 is a flow chart of transmission data write
processing in the basic control flow chart; and
[0128] FIG. 117 is a flow chart of multiplex data receive
processing in the basic control flow chart.
BEST MODE FOR CARRYING OUT THE INVENTION
[0129] FIG. 1 is a view of an entire system for an automobile to
which the present invention is applied, and FIG. 2 is a functional
block diagram of the system. Reference numeral 3 denotes a battery
which supplies power to the entire vehicle via a fusible link 4.
Reference numeral 10 denotes a power train control module (PCM)
which effects control of the fuel injection amount or the ignition
timing of an engine and control of an engine transmission and is
mowted in the proximity of the engine (for example, on an outer
wall of an intalce manitold, in the inside of a surge tank or the
like) around which sensors and/or actuators for controlling the
engine which is an object of control. A set of actuators as
electric loads such as several sensors such as an air flow meter
and a water temperature sensor, injectors 9 and a fan motor 35 for
cooling the engine are connected to the PCM 10. Reference numeral
11 denotes an anti lock braking system (ABS) control module, which
is mounted rearwardly of an engine room adjacent to an ABS
actuator. Reference numeral 16 denotes an air conditioner (A/C)
control unit which is disposed in the proximity of a dashboard on
the passenger's seat adjacent A/C sensors and actuators. Reference
numeral 25 denotes an air bag control module (SDM), which is mowted
in the proximity of a center console. Reference numeral 15 denotes
a navigation control module (NAVI), which is carried in the
proximity of a display section of an instrument panel. Reference
numeral 30 denotes a beacon control module (beacon), which is
installed in a trunk room. Reference numeral 14 denotes a body
control module (BCM), to which devices and/or key switches in the
proximity of a steering wheel are connected and which is installed
in the proximity of the dashboard. Each of the modules at least has
an arithmetic processing unit (cpu) communication means
(communication IC) for communicating data with the other
modules.
[0130] Each module is installed in the proximity of a sensor or a
device such as an electric load connected to the module so that the
harness length between the module and each of the devices connected
to the module may be minimized. A front integrated module (FIM) 5
is disposed at front locations of the engine room adjacent
headerlamps 1 and 6 or turn signal lamps 2a, 2b, 7a and 7b and is
connected so as to drive the headerlamps 1 and 6, the turn signal
lamps 2a, 2b, 7a and 7b, a horn 8 and so forth mounted in the
proximity. An instrument panel module (IPM) 17 is a module mounted
in an instrument panel meter case and drives lamps and meters in
the instrument panel. A driver door module (DDM) 18, a passenger
door module (PDM) 20, a rear right door module (RRDM) 27 and a rear
left door module (RLDM) 22 are carried on doors on the driver's
seat side, the passenger's seat side, the right side of the rear
seat and the left side of the rear seat, respectively, and door
lock motors 19 and 21, power window (19a, 20a) motors 73 and 106,
door lock switches 74 and 105, power window switches 75 and 104,
motors (not shown) for electrically driven mirrors 19b and 20b and
so forth are connected to them. A driver seat module (DSM) 26 and a
passenger seat module (PSM) 24 are mounted underneath the seats on
the driver's seat side and the passenger's seat side, respectively,
and electrically driven seat motors 111 to 113 and 123 to 125, seat
switches 114 and 122 and so forth are connected to them. A rear
integrated module (RIM) 29 is disposed at a front portion of the
trunk room adjacent tail lamps 32 and 33 and turn signal lamps 31
and 34 and is connected to drive, in addition to the tail lamps 32
and 33 and the turn signal lamps 31 and 34, a trunk opener motor
133, a rear defogger 134 and so forth. The FIM 5, RIM 29, IPM 17,
DDM 18, PDM 20, RRDM 27, RLDM 22, DSM 26 and PSM 24 have
communication means 52, 131, 84, 70, 102, 77, 136, 120 and 109 to
communicate data between different modules, and input/output
interfaces 51, 132, 85, 71, 103, 78, 137, 121 and 110 to which
sensors, switches and external electric loads are connected, but,
in the present embodiment, do not have an arithmetic processing
unit (CPU). (Naturally, they may have an arithmetic processing unit
(CPU)). As multiplexed communication lines along which data are
communicated between different modules, a line 12 is connected to
extend from the FIM 5 to the BCM 14, and a line 36 is connected to
extend from the BCM 14 to the RIM 29 while a line 39 is connected
to extend from the RIM 29 to the FIM 5, and the multiplex
communication lines are wired in a loop in the vehicle. The other
modules, that is, the IPM 17, DDM 18, PDM 20, RRDM 28, RLDM 22, DSM
26, PSM 24, PCM 10, ABS 11, A/C 16, navigation control module 15
and SDM 25 are connected branching from individually near locations
of the lines 12, 36 and line 39 arranged in a loop. In this manner,
since each module is disposed in the proximity of a device
connected to the module and input data and output data of any
device which is not connected to the module are transmitted or
received via the multiplexed communication lines, the necessity for
connection of the module to a device located remotely by a wire in
order to acquire data necessary for the module is eliminated, and
consequently, wiring lines for signal transmission, that is,
harnesses, can be reduced. A power supply line from the battery 3
is connected to the FIM 5 by a power supply line 40 via the fusible
link 4, and connected by a power supply line 13 between the FIM 5
and the BCM 10, by another power supply line 37 between the BCM 10
and the RIM 29 and by a further power supply line 38 between the
RIM 29 and the FIM 5, and is disposed in a loop in the vehicle
compled with the multiplexed communication lines 12, 36 and 39. The
IPM 17, DDM 18, PDM 20, RRDM 27, RLDM 22, DSM 26 and PSM 24 which
are modules which must operate irrespective of an ON or OFF
position of an ignition key switch 67 are connected branching from
near locations of the power supply lines 13, 37 and 38 arranged in
a loop so that electric power may be supplied to them. From the FIM
5, power is supplied via a power supply line 41 to the modules,
actuators and so forth of the PCM 10 and the ABS 11 mounted in the
engine room. From the BCM 10, power is supplied to the A/C 16,
navigation control module 15, SDM 25 and actuators and sensors
mounted in the compartment by power supply lines 42 and 43.
Further, from the RIM 29, power is supplied to the beacon 30 and
actuators and sensors mounted in the trunk room by a power supply
line 44. Since the power supply lines are wired in a loop in the
vehicle and the modules to which power is inputted from the power
supply lines wired in a loop and which supplies the power to the
different modules, actuators, sensors and so forth are disposed one
by one in the engine room, the compartment and the trunk room
(since, in the present embodiment, they are formed from the FIM,
BCM and RIM, respectively), such a situation that power supply
lines are wired in multiples in the vehicle is eliminated, and wire
harnesses in the vehicle can be further reduced.
[0131] FIG. 2 is a functional block diagram of the system. The FIM
5 includes a power supply switching supply circuit 53, an I/O
communication IC 52 and an I/O interface 51. A power supply line
from the positive termimal of the battery 3 is connected to the
power supply and switching circuit 53 via the fusible link 4, and
connected also to the RIM 29 via the power supply line 38. Further,
the power supply line from the battery is supplied to the BCM 14 by
the power supply line 13 via the power supply and switching circuit
53, and from the power supply and switching circuit 53, power is
supplied to such modules as the PCM 10 and the ABS 11, such
actuators as the injectors 9 and the fan motor 35 and sensors
installed in the engine room via the power supply line 41. The I/O
communication IC 52 is connected to the communication line 12 so
that it transmits and receives data to and from the other modules.
The ON/OFF of the power to be supplied to the power supply line 41
is controlled by data received by the I/O communication IC 52. The
I/O interface 51 is connected to the actuators for the headerlamps
1, 2, 6 and 7 and the horn 8 mounted in the proximity of the FIM 5
such that those actuators are driven by signals from the I/O
communication IC 52 and a signal (not illustrated in FIG. 2)
inputted to the FIM 5 is transmitted to the I/O communication IC
52. The RIM 29 includes a power supply & switching circuit 130,
an I/O communication IC 131 and an I/O interface 132 which are the
same as those of the FIM 5. From the power supply & switching
circuit 130, power is supplied also to the module of the beacon 30,
actuators and sensors (not shown in FIG. 2) installed in the trunk
room via the power supply line 44. The I/O communication IC 131 is
connected to the communication line 36 so that it transmits and
receives data to and from the other modules. The I/O interface 132
is connected to such actuators as the tail lamps 31, 32, 33 and 34,
trunk opener motor 133 and rear defogger 134 mounted in the
proximity of the RIM 29 such that it drives those actuators with
signals from the I/O communication IC 131 and transmits a signal
(not illustrated in FIG. 2) inputted to the RIM 29 to the I/O
communication IC 131. The BCM 14 includes a power supply/&
switching & circuit 66, a communication IC 65, a CPU 64 and an
I/O interface 63. The power supply lines are connected by the power
supply & switching circuit 66 of the BCM 14 and the power
supply & switching circuits 53 and 130 of the FIM 5 and RIM 29
and is connected in a loop passing the three modules. The BCM 14 is
mounted in the proximity of the driver's seat dashboard, and the
switches 67 around the driver's seat such as the ignition key
switch, headerlamp switch, turn signal switch and hazard lamp
switch, sensors, and actuators for a wiper motor (not shown), a
motor for an automatic antenna and so forth are connected to the
I/O interface 63. The BCM 14 manages and controls ON/OFF of power
to be supplied from the power supply & switching circuits 53
and 130 of the FIM 5 and RIM 29 and all of inputs and outputs of
the FIM 5, RIM 29, DDM 18, PDM 20, RRDM 27, RLDM 22, IPM 17, DSM 26
and PSM 24 in a centralized manner. As seen in FIG. 6, from the
power supply & switching circuit 66, power is supplied to the
modules (in the present embodiment, the navigation control module
15, A/C 16 and SDM 25) and sensors in the compartment, a room lamp
68 and the actuators such as the wiper motor, automatic antenna
motor and so forth in response to a state of the ignition key
switch. The communication IC 65 is connected to the communication
line 36 so that it transmits and receives data to and from the
other modules. The CPU 64 fetches input data for the electric loads
connected directly to the CPU 64 and data from the other modules
received by the communication IC 65, performs calculation
processing based on the data, outputs driving signals for the
actuators connected directly to the CPU 64 in response to a result
of the calculation and further transmits the result of the
calculation to the other modules via the communication IC 65. The
DDM 18, PDM 20, RRDM 27 and RLDM 22 are modules mounted on the
doors, and include power supply circuits 69, 101, 76 and 135 and
I/O communication ICs 70, 102, 77 and 136, and I/O interfaces 71,
103, 78 and 137, respectively. The power supply circuits 69, 101,
76 and 135 are configrexed so as to receive supply of power from
the power supply lines which are connected in a loop between the
modules of the BCM 14, RIM 29 and FIM 5 and supply the power to the
power supply of the modules and tp the actuators and to the
sensors. The I/O communication ICs 70, 102, 77 and 136 are
connected to the communication lines so that they transmit and
receive data to and from the other modules. The I/O interfaces 71,
103, 78 and 137 are connected to such actuators as the door lock
motors and the power windows (hereinafter referred to as P/W)
mounted in the individual doors such that they drive the actuators
with signals from the I/O communication ICs 70, 102, 77 and 136 and
transmit input signals from the P/W switches and switches regarding
the door locks to the I/O communication ICs 70, 102, 77 and 136.
The DSM 26 and the PSM 24 are modules mounted underneatu the
driver's seat and the passenger's seat, respectively, and include
power supply circuits 119 and 108, I/O communication ICs 120 and
109, and I/O interfaces 121 and 110, respectively. The power supply
circuits 119 and 108 are constructed so as to receive supply of
power from the power supply lines connected in a loop between the
BCM 14, RIM 29 and FIM 5 and supply the power to the power supply
of the modules, to actuators and to sensors. The I/O communication
ICs 120 and 109 are connected to the communication lines so that
they transmit and receive data to and from the other modules. The
I/O interfaces 121 and 110 are connected to the actuators such as
seat motors mounted in the proximities of them such that they drive
the actuators with signals from the I/O communication ICs 120 and
109 and transmit inputs signals of seat switches to the I/O
communication ICs 120 and 109. The IPM 17 is a module mounted in
the instrument panel meter and includes a power supply circuit 83,
an I/O communication IC 84 and an I/O interface 85. The power
supply circuit 83 receives supply of power from the power supply
lines connected in a loop between the BCM 14, RIM 29 and FIM 5 and
supply the power to the power supply of the module, to actuators
and to sensors. The I/O communication IC 84 is connected to the
communication lines so that it transmits and receives data to and
from the other modules. The I/O interface 85 is connected to
actuators of display lamps 86, 87 and 88 mounted on the instrument
panel such that it drives the actuators with signals from the I/O
communication IC 84 and transmits input signals from switches
provided on the panel to the I/O communication IC 84. The PCM 10,
ABS 11, navigation control module 15, A/C 16, SDM 25 and beacon 30
include power supply circuits 54, 61, 89, 93, 115 and 126,
communication ICs 57, 60, 91, 95, 117 and 128, CPUs 56, 59, 90, 94,
116 and 127 and I/O interfaces 55, 58, 96, 118 and 129 or an
operation and display unit 92. Those modules have CPUs and perform
calculation processing and communication control regarding
respective objects of control. The power supply circuits 54, 61,
89, 93, 115 and 126 are constructed so as to receive power supplied
thereto from the BCM 14, RIM 29 and FIM 5 and supply the power to
the power supply of the modules, to actuators and to sensors. The
communication Ics 57, 60, 91, 95, 117 and 128 are connected to the
communication line so that they transmit and receive data to and
from the other modules. The I/O interfaces 55, 58, 96, 118 and 129
are connected to actuators such as fuel supplying injectors of the
engine, driving solenoids for hydraulic valves for the ABS and the
blower motor mounted in the proximities of them such that they
drive them in accordance with results of calculation of the
respective CPUs and transmit input signals thereto to the CPUs 56,
59, 90, 94, 116 and 127. The I/O communication ICs built in the FIM
5, RIM 29, DDM 18, PDM 20, RRDM 27, RLDM 22, IPM 17, DSM 26 and PSM
24 have respective unique physical addresses and are each
constructed such that it fetches, when an address signal same as
the physical address of the I/O communication IC appears on the
communication lines, a signal following the address signal, outputs
the signal to the I/O interface, then outputs input data from an
electric load connected to the I/O interface to the communication
lines, and, if a change appears in the electric load connected to
the I/O interface, then transmits a function address representing
contents that "input data from an electric load to the I/O
interface are transmitted" first and then outputs input data of the
I/O interface to the communication line. Since the communication
function is restricted in the manner, a module construction which
does not require a CPU can be used. A module having this I/O
communication IC is generally referred to as LCU (Local Control
Unit). The communication ICs built in the BCM 14, PCM 10, ABS 11,
navigation control module 15, A/C 16, SDM 25 and beacon 30 are
constructed so that control of transmission and reception is
performed by a CPU. In particular, also the timing at which
transmission is to be started and the transmission data are
controlled by a signal from the CPU, and not only reception
according to the physical address peculiar to the CPU but also a
function address can be discriminated by the CPU to fetch or ignore
data following the function address. In the following, operation is
described with reference to FIG. 3. As an example, a case wherein
the P/W raising switch on the passenger's seat side mounted on the
door on the driver's seat side is depressed to raise the P/W on the
passenger's seat will be described. If the P/W raising switch on
the passenger's seat side mounted on the door on the driver's seat
is depressed, then the level of a signal of the passenger's seat
P/W raising switch inputted to the DDM 18 changes from high to low.
This variation in input acts as a trigger, and the I/O
communication IC 70 of the DDM 18 starts transmission of all input
data connected to the I/O interface 71 and outputs a signal to the
communication lines. The signal outputted includes information
representing transmission of the input data of the DDM 18 and the
actual input data. The information outputted to the communication
lines is inputted to all of the modules. However, the I/O
communication IC ignores following data since the information does
not present the physical address of the I/O communication IC. The
CPUs of the modules in which communication ICs are built are
programmed so that they individually discriminate their function
addresses and the communication ICs other than that of the BCM 14
ignore following data. The BCM 14 fetches the input data of the DDM
outputted from the DDM 18 and performs discrimination calculation
processing based on the data. Whereas this discrimination
calculation processing may be performed immediately after the data
are received, in the present embodiment, it is executed after each
fixed interval of time. Since the P/W motor for the passenger's
seat is changed from stopping to driving based on a result of the
discrimination calculation processing, the BCM 14 outputs the
physical address of the PDM 20 connected to the passenger's seat
P/W motor, whose output should be changed, to the communication
lines and then transmits output data to all of the actuators
connected to the PDM 20. Whereas the signal on the communication
lines outputted from the BCM 14 is inputted to all of the modules,
only the PDM 20 whose physical address coincides with the signal
receives the data. The PDM 20 outputs the received data to the I/O
interface 103 to drive the actuator. In this instance, since the
signal of the P/W motor is ON, the P/W motor operates to raise the
P/W. According to such a communication procedure as described
above, the P/W of the passenger's seat can be raised by depressing
the P/W raising switch on the passenger's seat side mounted on the
door of the driver's seat. It is to be noted that, though not
shown, where the vehicle is a four-door vehicle, four P/W rolling
up switches are provided for the DDM 18 and also four P/W rolling
down switches are provided. In this manner, input data to the LCU
are all inputted to the BCM 14, and the BCM 14 calculates, based on
the input data, control data for driving of all of the actuators
connected to the LCU and transmits the control data by
communication to the LCU. Since calculation processing for the
control objects of the LCU is all performed by the BCM 14 in this
manner, the LCU can be constructed such that it does not require a
CPU which performs calculation processing. Between those modules
which include a CPU, transmission and reception between the modules
based on a physical address and simultaneous transmission and
reception between a plurality of modules based on a functional
address are performed. As an example, vehicle speed data are
described. A vehicle speed sensor 1008A is connected to the PCM 10
(refer to FIG. 62) so that a vehicle speed is detected by the PCM
10. The PCM 10 outputs a functional address representing contents
that vehicle speed data are outputted to the communication lines
and then outputs the vehicle speed data.
[0132] Since the LCU cannot receive a functional address, it cannot
fetch vehicle speed data. Each of the modules which require such
vehicle speed data (in the present embodiment, the navigation
control module 15, ABS 11, SDM 25, beacon 30 and BCM 14)
discriminates the functional address and, if it discriminates that
vehicle speed data are transmitted, receives following vehicle
speed data and reflects the vehicle speed data on its respective
control. In the present embodiment, the output of the LCU cannot be
controlled directly from any module other than the BCM 14 which
includes a CPU. All information necessary to control the LCU is
inputted to the BCM 14 so that the output of the LCU is controlled
by the BCM 14.
[0133] FIG. 4 is a state transition table of operation. The state A
is a state wherein the battery is disconnected and all of the
modules are unpowerwd.
[0134] The state B is a state wherein those modules to which power
is always supplied while the battery is connected (in the present
embodiment, the BCM 14, FIM 5, RIM 29, DDM 18, PDM 20, RRDM 27,
RLDM 22, IPM 17, DSM 26 and PSM 24) are operative, but power is not
supplied to the other modules. The state C is a state wherein those
modules to which power is supplied in the state B stand by for
operation, that is, sleep. The state D is a state wherein the
ignition key switch is at the accessory position (hereinafter
referred to as ACC) and the modules to which power is supplied in
the state B are operative and besides power is supplied to those
modules to which power is supplied when the ACC is ON (the
navigation control module 15, the A/C 16 and a radio and so forth
which are not described in the present embodiment) so that the
modules are operating. The state E is a state wherein the ignition
key switch is at the ignition position hereinafter referred to as
IGN) and the modules to which power is supplied in the state B are
operative and besides power is supplied to those modules to which
power is supplied when the IGN is ON (in the present embodiment,
the PCM 10, ABS 11, SDM 25 and beacon 30) so that they are
operating. If the battery is connected in the state A, then the BCM
14, FIM 5, RIM 29, DDM 18, PDM 20, RRDM 27, RLDM 22, IPM 17, DSM 26
and PSM 24 start their operation. The I/O interfaces of the FIM 5,
RIM 29, DDM 18, PDM 20, RRDM 27, RLDM 22, IPM 17, DSM 26 and PSM 24
are put into a high impedance state which is an all port initial
state, and the I/O communication IC is put into a standby state.
The BCM 14 transmits, after the initialization of the CPU 64,
communication IC 65 and I/O interface 63, input/output directions
of the I/O interfaces of all of the LCUs and initial output data to
the LCUs from the communication lines to effect initialization of
all of the LCUs. Thereafter, input data to all of the LCUs are
received and ordinary control is entered. In this state, if some
operation is performed, control corresponding to the operation (for
example, door locking control) is performed. If, in this state, no
operation is performed for more than a predetermined time (in the
present embodiment, 30 seconds) and the state wherein all outputs
are off continues, then the BCM 14 discriminates that the vehicle
is in a state left as it is and executes a procedure of entering a
sleep state of the state C. First, the BCM 14 outputs a sleep
command at least once to the communication lines so that all of the
LCUs may enter a sleep state. Each of the LCUs having received the
sleep command stops an oscillation circuit of the I/O communication
IC or the like to enter a sleep state. The BCM 14 thereafter puts
itself into a sleep state. Consequently, the state C is
established. If wake-up requirements are satisfied in the sleep
state of the state C, then the system now enters the state B, in
which it starts its operation. The procedure of the wake-up is such
that, when an input to an LCU changes, then the communication IC of
the LCU varies the potential of the communication lines, and if the
variation of the communication line is detected by the
communication IC of the BCM, then the communication IC generates a
wake-up signal to the CPU and the CPU starts its operation to
operate the communication IC. Then, a wake-up command is
transmitted from the communication IC to all of the LCUs to wake
up, and the communication IC starts its operation. All of the LCUs
start their operation in response to the wake-up command. As an
example, when the vehicle is in a state left as it is, that is,
when the system is in the state C, if a driver of the vehicle
inserts a key into a key cylinder of a door and unlocks the door,
then the input to a door unlock detection switch connected to the
DDM 18 varies, and in response to the variation, the system wakes
up in the procedure described above and enters the state B in which
its starts its ordinary operation. Or, according to another wake-up
procedure, when an input signal connected directly to the BCM
varies, then a wake-up signal for the CPU is generated in response
to the signal of the variation and the CPU starts its operation to
render the communication IC operative. Thereafter, the
communication IC transmits a wake-up command to all of the LCUs so
that they may wake up to start their operation. All of the LCUs
start their operation in response to the wake-up command.
Transition from the state C to the state B occurs in this manner.
If the ACC is turned on when the system is in the state B, then the
system enters the state D. If the ACC switch connected to the BCM
14 is switched on, then the BCM 14 starts supply of power from the
power supply & switching Circuit 66 to the navigation control
module 15, the A/C 16, and, though not shown in FIG. 2, those
modules, sensors and actuators to which power is supplied when the
ACC is on such as a radio. Further, the BCM 14 transmits a control
signal via the communication lines so that power may be supplied
from the power supply & switching circuit 130 of the RIM 29 to,
though not shown in FIG. 2, a CD changer and so forth. The RIM 29
which receives the control signal starts supply of power from the
power supply & switching circuit 130. If the IGN is switched on
when the system is in the state B or the state D, then the BCM 14
starts supply of power from the power supply & switching
circuit 66 to the module of the SDM 25, sensors, actuators and so
forth. The module to which power is supplied (in the present
embodiment, the SDM 25) starts its ordinary operation after it
performs initialization. Further, the BCM 14 transmits a control
signal via the communication line so that power may be supplied
from the power supply & switching circuits 53 and 130 of the
FIM 5 and the RIM 29 to the line 41 and the line 44, respectively.
The FIM 5 having received the control signal starts supply of power
from the power supply & switching circuit 53 to the line 41.
The modules to which power is supplied (in the present embodiment,
the PCM 10 and the ABS 11) start their operation after they
individually perform initialization. Similarly, the RIM 29 having
received the control signal starts supply of power from the power
supply & switching circuit 130 to the line 44. The module to
which power is supplied (in the present embodiment, the beacon 30)
starts its ordinary operation after it performs initialization. If
the IGN is switched off, then transition from the state E to the
state D occurs, and if the IGN is off and the ACC is off, then
transition from the state E to the state B occurs. The requirement
for transition from the state D to the state B is that the ACC is
switched off. Transition to the state A occurs from any other state
if the battery is disconnected. Since power supply of the entire
vehicle is managed by control signals by multiplexed communication
from the BCM 14 and modules from which power is supplied are
disposed in the proximity of modules, sensors and actuators to
which power is supplied in this manner, the length of the power
supply lines can be made short.
[0135] In the following, the various elements of the embodiment of
the present invention are described in more detail with reference
to the drawings.
[0136] Description of Composite Cable
[0137] FIG. 5 is a view showing an internal construction of a power
supply line and a multiplex communication line. In the present
embodiment, a structure of a two core braided cable which includes
a power supply line 13 (37, 38) for supplying power and a multiplex
communication line 12 (36, 39) as well as a shield layer SA which
forms a short-circuiting sensor is taken. In the following
description, the structure is referred to as composite multiplex
communication cable 5Z. The composite multiplex communication cable
5Z is different from an ordinary shield cable in that a potential
is applied to the shield layer. Since a predetermined potential is
applied via a terminal 5C, if the composite multiplex communication
cable 5Z is rubbed against or pinched by the vehicle body to break
a insulating resin protective sheath 5B, the shield layer is first
brought into contact with the vehicle body and the potential
thereof drops to the ground (vehicle body ground). Therefore, by
supervising the potential, a sign of occurrence of a
short-circuiting accident of the power supply line can be
discriminated. Further, where the shield layer is connected to the
ground with a low impedance using a capacitor, there is an effect
also for prevention of invasion of external noise of high
frequencies or of emission of high frequency noise. Further, where
the shield layer is made of a metal, since it is difficult to cut,
there is an effect also for assurance of time until a
short-circuiting accident of the power supply line occurs.
[0138] The composite cable is disclosed in detail in Japanese
patent application Ser. No. 07/32647.
[0139] Description of BCM
[0140] FIG. 6 is a detailed block diagram of the BCM (body control
module). This module is disposed in the neighborhood of the dash
panel, and principally performs fetching of switches operated by a
driver, supply of power to other control units installed in the
proximity of the dash panel and control as a center of the power
supply network using a power supply multiplex communication line
which will be hereinafter described.
[0141] An actual controlling method is hereinafter described with
reference to a flow chart.
[0142] The BCM 14 is connected via composite multiplex
communication cables 5Z to nine modules for effecting power supply
management, including the FIM (front integration module) 5 which
effects power supply management of a front part of the vehicle, the
DDM (driver door module) 18 which effects power supply management
of the door on the driver side, the PDM (passenger door module)
which effects power supply management of the door of the assistant
& driver side, the RLDM (rear left door module) which effects
power supply management of the rear door on the driver side, the
RRDM (rear right door module) which effects power supply management
of the rear door on the driver's seat side, the IPM (instrumental
panel module) which effects power supply management of the meter
panel of the instrument panel forwardly of the driver's seat, the
RIM (rear integration module) which effects power supply management
of a rear part of the vehicle, the DSM (driver's seat module) which
effects power supply management of the driver's seat and the PSM
(passenger seat module) which effects power supply management of
the seat of the passenger's seat side, and is the center which
controls the modules in a concentrated manner.
[0143] Accordingly, only the BCM 14 includes a built-in
microcomputer among the modules. It is to be noted that the reason
why a microcomputer is built only in the BCM is that the system can
be constructed at a low cost, but a microcomputer may otherwise be
built in all of the modules.
[0144] The BCM 14 is connected at an input terminal 14A thereof to
the composite multiplex communication cables 5Z which form a loop.
Consequently, the BCM 14 is connected to the two composite
multiplex communication cables 5Z, and the two communication lines
12 and 36 are logically Ored via internal communication lines 601
and 602 and inputted to the communication IC 65 so that multiplex
communication is performed. The reason why the communication lines
12 and 36 are logically ORed is that it is intended to prevent
disconnection or short-circuiting of one of them from having an
influence on the other of them.
[0145] A potential signal of the shield line 5C is inputted to a
short-circuiting detection circuit 606 via internal signal lines
604 and 605, and a state signal of the shield line 5C is inputted
from the short-circuiting detection circuit 606 to the CPU 64, by
which it is used for means for detection of a trouble of the
composite multiplex communication cable 5Z.
[0146] Details of the short-circuiting detection circuit 606 are
shown in FIG. 7. In the present embodiment, the short-circuiting
sensor shield line 5C interposed between different modules is fixed
to a potential of 2.5 V, which is equal to one half a voltage Vcc
(5V), by resistors R1 and R2. The resistor R1 serves also to
restrict electric current to flow when the short-circuiting sensor
is short-circuited. Reference character S denotes a comparator, and
a Schmitt circuit is formed from resistors R3 to R6. The threshold
level of the Schmitt circuit is set to a voltage lower than 2.5 V
so that, when the potential of the short-circuiting sensor is lower
than the threshold level, the comparator S may output "H".
Accordingly, when the output signal of the short-circuiting
detection circuit 6 is "H", the potential of the short-circuiting
sensor is low. In short, this indicates that the short-circuiting
sensor is in contact with an element having a low potential, and
after all, this indicates that the composite multiplex
communication cables are damaged and contact with the vehicle body
ground.
[0147] The power supply lines are distributed by internal power
supply lead-in lines 608 and 609 to a path inputted to a power
supply switching circuit 610 and another path 612 logically ORed by
diodes and inputted to a power supply circuit 611. The path which
passes the diodes is used so that, even if switches in the inside
of the power supply switching circuit 610 are completely off,
supply of power to a microcomputer 607 or the communication IC 65
may not be cut off.
[0148] The power supply switching circuit 610 is controlled in
accordance with a power supply switching signal 613 by the CPU 64
and is a circuit which switches to select one of the internal power
supply lead-in lines 608 and 609 to be used. The power supply
switching circuit 610 is provided in order that, even if one of the
two power supply multiplex communication cables is damaged and put
into a state wherein it fails to supply power, this may not have an
influence of the other power supply multiplex communication cable.
By this means, even if short-circuiting of a power supply multiplex
communication cable to the vehicle body ground occurs, the damaged
portion can be opened between the power supply switching
circuits.
[0149] Situations in which power supply switching is required and
states of the change-over switch are shown in FIG. 8 and Table
1.
1 TABLE 1 Failure Failure Normal detected detected SW-A ON OFF ON
SW-B ON ON OFF
[0150] Further, an actual state is described with reference to FIG.
9. In FIG. 9, in order to facilitate understandings, notice is
taken of the power supply switching circuit to show it in an
enlarged form. FIG. 9 illustrates a state of the power supply
switching circuit when the power supply multiplex communication
cable between the FIM and the BCM is short-circuited to the vehicle
body ground, and the switch B on the FIM side is switched off while
the switch A on the BCM side is switched off so that the circuit of
the power supply line at the location at which the power supply
multiplex communication cable is short-circuited to the vehicle
body ground is shut-off and no current flows any more.
[0151] A power supply circuit 411 (611) has two power supply input
paths as described hereinabove, and details of the same are
described with reference to FIG. 10. FIG. 10 is an internal block
diagram of the power supply circuit 411 (611). The power supply
circuit 411 (611) receives two inputs of power supply from a power
supply switching circuit 410 (610) and a path 412 (612) described
above. The internal circuit has two independent circuit
constructions and includes, as common circuit blocks, a power
supply reverse connection protection circuit which prevents a break
of the circuitry even if the battery is mounted with the (+)
terminal and the (-) terminal thereof connected reversely, a surge
protection circuit for protecting the circuitry from a high voltage
which is generated when a battery terminal is disconnected during
driving of the vehicle or in a like case, and a low-pass filter for
suppressing a sudden variation of the battery voltage. Battery
power from the power supply switching circuit 410 (610) having
passed through those circuits is used as a voltage source 414 (614)
for driving loads connected to the individual modules which effect
power supply management.
[0152] The power from the path 412 (612) thereafter passes a power
instantaneous disconnection compensation circuit which prevents
interruption of power supply to the control circuit even if power
supply disconnection for a short time which arises from chattering
of a connector or a terminal occurs and then passes a control
circuit driving power production circuit in the form of a constant
voltage power supply circuit which produces power for the control
circuit (in the present embodiment, 5 V), and is used as driving
power for the microcomputer 64, the communication IC 65 and so
forth.
[0153] The power supply line 614 outputted from the power supply
circuit 611 is inputted to a control unit supply power switching
circuit 616 and an interruption circuit 617. The control unit
supply power switching circuit 616 is a switching circuit which
supplies power to the other control units connected to the BCM, and
is switched on and off by a control signal line 618 of the
microcomputer 64. Incidentally, each of various control units
employed in current vehicles (for example, a PCM, an ABS and so
forth) has, in the inside thereof, a power supply protection
circuit which prevents failure of the control unit even if the
battery voltage becomes an abnormal voltage. Since this circuit is
similar to that of the power supply circuit 611 described
hereinabove with reference to FIG. 10, if a power supply module is
used to supply power to various control units as in the present
invention and the power supply protection circuit is built in on
the power supply side, then it is possible to omit power supply
protection circuits from the control units to which power is to be
supplied. In other words, if the number of various control units to
which power is to be supplied is large, then the cost can be
reduced as much as the power supply protection circuits can be
omitted.
[0154] It is to be noted that, in the present embodiment, when an
accessory ACC contact 629 of the key switch is on, power is
supplied to the navigation unit 42, and further, when an ignition
ON contact 630 of the key switch is switched on, supply of power to
the SDM 25 and the air conditioner unit 16 is started. Reference
symbol ST denotes a starter starting switch of the key switch.
[0155] The cut off circuit 617 is provided in order to cope with
two situations described below.
[0156] First, the cut-off circuit 617 is used in order to reduce
the current consumption of a driver 621A built in an output
interface 621 when it is not used. The driver used in the present
embodiment is formed from a driver called IPD (intelligent power
device) as shown in FIG. 12. In this IPD, short-circuiting or
disconnection of a load to be driven is diagnosed by a diagnosis
circuit 621C and a result of the diagnosis is outputted to the
microcomputer 64. The diagnosis circuit 621C includes a protection
circuit which detects, when over-current flows through an element
621B, such over-current and controls a driving signal 622a to limit
the current so that the diagnosis circuit 621C itself may not be
broken. Consequently, the current consumption (dark current) when
the element 621B is inoperative is higher than that of an ordinary
driving element. Accordingly, use of a large number of such drivers
may possibly cause exhaustion of the battery. In order to prevent
this, when the driver 621A need not be driven, power to be supplied
to the driver 621A is cut-off on the upstream side to prevent
consumption of current.
[0157] Second, the cut-off circuit 617 is provided for protection
against a failure of the driver 621A itself. In particular, when
the cut-off circuit 617 supplies power to its load although a
driving signal is not received from the CPU 64, while it is
conventionally impossible to stop the power supply, in the present
embodiment, an cut-off signal 619a from the microcomputer 64 to the
c/o circuit 617 is cut-off to cut-off power, which is to be applied
to the driver, on the upstream of the driver to stop supply of
power to the load.
[0158] A detailed construction of the cut-off circuit 617 is shown
in FIG. 11. The cut/off circuit 617 includes a switching device
617A for which a semiconductor such as an FET is used, and a state
detection means 621D for monitoring an on-off situation of the
switching device 617A. The switching device 617A is normally on in
accordance with the cut-off signal 619a from the microcomputer 64.
Also when the microcomputer 64 detects a trouble of the switching
device 617A from the monitor signal from the state detection means
621D, the driving signal 619a disappears and the switching device
617A is switched off. Operation of the device 617A is indicated in
Table 2.
2TABLE 2 Normal Output driver failed Not used ON OFF OFF
[0159] The communication IC 65 is an IC for exclusive use which
effects data communication with the other modules using the
multiplex communication lines built in the composite multiplex
communication cables. Communication of information obtained by
communication or data to be transmitted is performed over a data
bus 620 connected to the microcomputer 64.
[0160] The output interface 621 has a plurality of drivers 621A
built therein for driving various electric load apparatus connected
to the module 14, and one of the drivers is shown in FIG. 12. The
output interface 621 shown includes an IPD having such a diagnosis
circuit 621C as described above and a state detection circuit 621D
for confirming whether or not the IPD operates normally.
[0161] A signal line set 622 connected to the microcomputer 64
includes, as shown in FIG. 12, three signals of a diagnosis signal
622b, a driving signal 622a and an device diagnosis signal
622c.
[0162] The driving signal 622a is a signal for turning the IPD on.
When the driving signal 622a is "H", power of a power supply line
614a is outputted to the room lamp 32, which is an electric load,
so that the lamp is lit.
[0163] The diagnosis signal 622b indicates a functional situation
of the IPD and is a diagnosis signal line for notifying whether the
load is in a short-circuited state or in an open (disconnected)
state.
[0164] The device diagnosis signal 622c is a failure diagnosis
signal for detection of a failure of the IPD device 621A itself
described above.
[0165] How to detect that the room lamp 32 connected to the BCM is
short-circuited or open or that the IPD device is in failure is
described with reference to Table 3.
3 TABLE 3 Abnormal operation Normal Element Load Load short-
operation failed open circuited Driving H L L H L H signal
Diagnosis H L -- H H L signal Element H L H L L L diagnosis
signal
[0166] As described above, the IPD, the element itself, has a
function of discriminating a state of a load connected thereto, and
as seen in Table 3, a "load open" and a "load short-circuited" can
be discriminated from the relationship between the diagnosis signal
and the driving signal.
[0167] On the other hand, if the IPD element itself fails, then
also the diagnosis signal cannot be relied, and therefore, an
output signal of the IPD is monitored as an element diagnosis
signal as seen in FIG. 12. An impedance converter A and a resistor
R have a function of preventing an electric influence on the IPD
and another function of stabilizing the signal level when the
element failure diagnosis signal is opened.
[0168] This circuit monitors a voltage applied to the room lamp 32
(load) after all, and by monitoring the three of the driving
signal, diagnosis signal and element diagnosis signal, all states
indicated in Table 3 can be grasped. In Table 3, the portion
indicated by "-" (dash) represents whichever one of "H" and "L" is
allowed. Accordingly, if the driving signal is "H" and the
diagnosis signal is "H" while the failure diagnosis signal then is
"L", it is indicated that, although it is discriminated that the
output state of the IPD is correct, no outputting is performed. On
the other hand, when the driving signal is "L" and the failure
diagnosis signal then is "H", it is indicated that no outputting is
performed irrespective of the discrimination that the output state
of the IPD is normal although the IPD is not driven. Further, when
the driving signal is "L" and the failure diagnosis signal then is
"H", outputting of the IPD is performed although the IPD is not
driven.
[0169] In this instance, since both of the two cases are in
abnormal states, it may be determined that the IPD is in failure.
Then, when such a situation is entered, a secondary accident can be
prevented by notifying to a driver of the vehicle or the like by
sound or by an alarm lamp or the like that a trouble has occurred
and by switching off the switching element 617A of the cut-off
circuit 617. A number of such drivers 621 A equal to at least the
number of electric loads connected to the output interface 621 are
provided in the output interface 621.
[0170] An input interface 623 is an aggregate of waveform shaping
circuits for discriminating which one of the switches 25 to 31
connected to the BCM is on. The internal circuit of the input
interface 623 is shown in FIG. 13. The reason why only one circuit
is shown in FIG. 13 is that the other circuits are omitted because
all of the circuits are the same, and actually, a number of same
circuits equal to the number of switches are built in the input
interface 623. Each of the switches is pulled up to a battery
voltage (power supply line 14) by a resistor R10, and thereafter,
it passes a low-pass filter formed from a resistor R11 and a
capacitor C10 and the high voltage side is clamped by a Zener diode
Z10. In short, when the switch is off, ""H" is outputted, but when
the switch is on, "L" is outputted. Those signals are inputted to
the microcomputer 64 via an input signal line 624.
[0171] It is to be noted that switches connected to the input
interface 623 of the BCM include two switches for generation of
left and right signals for turn switches to be used for declaration
of turning to the right and the left, two light switches for
lighting side marker lamps and headerlamps, and three switches of
the accessory ACC switch 629, the ignition power supply switch 630
and a switch 631 for turning on the engine starter motor, which are
controlled by the key switch. In the embodiment, an automatic
antenna motor 633 and a wiper motor 634 are further connected to
the output interface 621 of the BCM.
[0172] An automatic antenna switch 635, a wiper switch 636, a speed
changing resistor 636a and a out side near view mirror control
switch 637 are connected to the input interface 623.
[0173] Since power supply lines are wired in a loop in the vehicle
and control units such as a BCM and an FIM for controlling electric
loads are connected to intermediate portions of the power supply
lines or to power supply lines branching from the power supply
lines so that power is supplied from the power supply lines of the
control units to terminal electric loads, there is no need of
laying a plurality of power supply lines long to each control unit
and there is an effect in reduction of power supply lines. Further,
since they are integrated with data mwltiplexing wiring system,
also information of a large number of operation switches can be
fetched collectively, and since shorter wire harnesses to the
switches can be used by transmitting the switch information by the
data communication lines, saving of wires can be achieved. It is to
be noted that the power supply & switching circuit 66
(indicated by dotted lines) formed between the connector section
14A of the BCM 14 and the output interface 621 and output terminal
14B can be regarded as a power supply relay circuit. Then, the BCM
itself can be regarded as one of power supply relay terminals.
[0174] Description of FIM
[0175] FIG. 14 is a block diagram of the FIM which is disposed at
the front part of the vehicle and effects power supply management
of the front part of the vehicle. The FIM is basically different
from the BCM in that it does not include a microcomputer nor an
input interface circuit and consequently in that the signals
inputted to and outputted from the microcomputer in the BCM are
inputted to the communication IC 52.
[0176] In the present embodiment, the FIM controls two groups
including a group which effects supply of power to the ABS control
unit 11 and the ABS solenoid 62 and effects supply of power to the
PCM control unit 10, the fan motor 35 for an engine cooling
radiator and the fuel injectors 9 to the engine, and another group
which effects driving of the horn 8, headerlamps 1 and 6, clearance
lamps 1a and 6a, and front turn signal lamps 2a, 2b, 7a and 7b.
Since the FIM does not fetch an input signal, the input interface
provided in the BCM is eliminated from the FIM.
[0177] For the communication IC 65 used for the BCM and. the
communication IC 52 used for the FIM, communication Ics of
different types are used. The former is of the type which cannot
perform data communication unless it is used together with a
microcomputer while the latter is of the type which can perform
data communication even if it is not used together with a
microcomputer. While details of the communication IC 52 of the
latter are hereinafter described, if data communication is allowed
without using a microcomputer in this manner, a unit of an object
of communication is not necessary required to have a microcomputer
built therein, and consequently, there is a merit in that reduction
in cost is allowed.
[0178] A short-circuiting detection circuit 406 and a switching
circuit 410, a power supply circuit 411, an cut-off circuit 417, a
switching circuit 416 and an output interface 421 which form the
power supply & switching circuit 53 have same constructions as
those of the BCM described above, and accordingly, description of
them is omitted. Further, details of operation are hereinafter
described with reference to a flow chart.
[0179] Description of DDM
[0180] FIG. 15 is an internal block diagram of the DDM 18 of a
power supply module built in the inside of the driver side door.
The door has a movable hinge element, and it is difficult to assure
a space in which a wire harness is to be wired. Therefore, the
present embodiment has a construction wherein, avoiding to wire the
composite multiplex communication cables in a loop, the DDM is
connected to a single composite multiplex communication line 5Za
branched by a T-shaped branching connector 50A shown in FIG. 22.
Accordingly, the DDM 18 does not adopt such a power supply
switching circuit 410 or 610 as is adopted by the BCM or the
FIM.
[0181] Basically, an cut-off circuit 517, an output interface 521
and an input interface 523 have similar constructions to those of
the BCM or the FIM, and the DDM 18 is characterized in that a power
supply circuit 511 has a simplified construction.
[0182] Details of the power supply circuit 511 are shown in FIG.
16. Since the power supply circuit 511 does not adopt a power
supply switching circuit, power supply is not cut-off completely,
and consequently, the two power supply paths, which are independent
of each other in the BCM, are joined together while a driver
driving power supply is branched from between a low-pass filter and
a instantaneous power supply disconnection compensation circuit.
Since the other circuit construction itself of the power supply
circuit is He same as that of FIG. 10, description of the same is
omitted.
[0183] The DDM 18 principally includes a switch 75 and a motor 7-3
for operating the power window P/W, a switch 74 and a motor 19 for
operating the door lock, and a switch 74A for detecting whether or
not the door is in a locked state. Also a motor 181A for driving a
out side Rew view mirror 181 is connected to the output interface
521. A control switch for the motor 181A is connected to the input
interface 624 of the BCM. It is to be noted that switches 74 for
operating the door lock are switches provided only for the driver
side, and by operating this switch, all of the door locks can be
operated collectively.
[0184] General operation is hereinafter described with reference to
a flow chart.
[0185] Description of PDM, RRDM and RLDM
[0186] FIG. 17 is an internal block diagram of the power supply
modules built in the insides of the doors other than the driver
side door. In this instance, the power supply modules signify the
PDM built in the inside of the passenger side door, the RRDM built
in the inside of the rear right door and the RLDM built in the
inside of the rear left door.
[0187] Those modules have basically the same construction as that
of the DDM, but are different in that dling up and down switches
104 (82, 138) for the power window and a door lock sensor 105 (81,
139) are connected to an input interface 723 and the door lock
motor 21 (28, 23) and the P/W motor 106 (80, 140) are connected to
an output interface 721.
[0188] It is to be noted that a out side rear view mirror motor
181B is connected to the output interface only of the PDM.
[0189] Description of IPM
[0190] FIG. 18 is an internal block diagram of the IPM installed in
the inside of the driver's seat meter panel. The IPM is a module
which effects fetching of an input signal which cannot be inputted
to the BCM and drives various display lamps and alarm lamps
installed in the meter panel. In the present embodiment, a parking
brake switch 830, a foot brake switch 831, a trunk open switch 832
and so forth are connected to an input interface 823, and, as
display lamps and alarm lamp for headerlamps, stop lamps and
sofreth, an SDM alarm lamp, an ABS alarm lamp, malfunction
indicator lamps for the composite multiplex communication cable and
so forth are connected to an output interface 821.
[0191] Also the present module has basically the same circuit
construction as that of the DDM, but it is different only in the
apparatus which are connected to the input interface and the output
interface.
[0192] Description of RIM
[0193] FIG. 19 is an internal block diagram of the RIM disposed in
the rear part of the vehicle. The RIM has a construction similar to
that of the FIM and is a power supply module which drives electric
loads concentrated in the rear part of the vehicle.
[0194] In the present embodiment, the RIM drives a trunk opener
motor 133, tail lamps 32, 33, stop lamps 31a, 34a and turn signal
lamps 31, 34. Further, the beacon 30 is connected to the RIM from a
power supply circuit 911 via a power supply line 914a and a
switching circuit 916. As shown in FIG. 2, the control panel,
display unit and loudspeaker for guidance by voice are connected to
an I/O interface 129 of the beacon unit.
[0195] Since the constructions of the internal blocks are same as
those of the circuitry of the FIM except that no input interface is
provided, description of them is omitted.
[0196] Description of DSM and PSM
[0197] FIG. 20 is an internal block diagram of the DSM and the PSM
disposed in the proximities of the driver's seat and the passengers
seat, respectively. Each of the DSM and the PSM employs motors in
order to adjust the position of the seat (forward and backward
sliding positions, forward and backward reclining positions and the
height), and switches for such adjustment are provided at portions
of the seat. Further, the respective switches are connected to the
input interfaces of the DSM and the PSM and the respective motors
are connected to the output interfaces of the DSM and the PSM.
[0198] As described above, since power supply modules connected by
power supply paths are disposed together with control units to
which power supply is required or disposed in the proximities of
locations where electric loads to be driven are concentrated, a
plurality of power supply lines to a control unit or power supply
lines to electric loads can be integrated, and besides, since the
lengths of the power supply lines can be made short, there is an
effect in saving of power supply lines. Further, where the power
supply lines are integrated with an intensive wiring system, by
collectively fetching information of a large number of operation
switches and sending the switch information to the data
communication lines, short wire harnesses can be used also for wire
harnesses to the individual switches, and consequently, saving of
lines can be achieved. Further, since a semiconductor is used for a
switching device for controlling power supply to an electric load
to form the switching device as an intelligent switching device and
besides an cut-off circuit is provided, also when the electric load
is short-circuited, the device can be prevented from being broken.
As a result, there is a merit in that a fuse box for the vehicle
and fuses for individual electric loads can be eliminated.
[0199] Description of Connector
[0200] By the way, for such a module as the BCM or the FIM to which
two composite multiplex communication cables each integrated with a
power supply line are inputted, a connector 5W shown in FIG. 21 is
used. In FIG. 21, when a module is to be connected to the wiring
side connector 5W, a dummy connector 5X is removed, and instead, a
terminator of the module is inserted to establish connection. Same
reference symbols as those of FIG. 6 denote same members. For such
a module as the DDM or the PDM to which one composite multiple
communication line is inputted, such a branching connector as shown
in FIG. 22 is used. Referring to FIG. 22, when power supply lines
for a module are to be branched from the power supply lines, the
power supply lines are separated and wiring connectors are
connected to ends of the power lines and inserted into two
terminals of the T-shaped branching connector while wiring
connectors on the module side are inserted into the remaining one
terminal of the T-shaped branching connector to establish
connection.
[0201] Description of Additional Module
[0202] In the meantime, in recent years, a consumer having
purchased a vehicle frequently attaches a car audio set, a
navigation apparatus or a like apparatus, and if a additional
terminal by which a power supply module can be added is provided in
the proximity of the passenger's seat dash panel of a vehicle or in
the trunk room in order to cope with such a need as just mentioned,
then supply of power can be performed readily and safely.
[0203] Where two power supply multiplex communication cables are
required, a dummy connector called terminator is connected to a
additional connector of the type of FIG. 21 to form a loop, and
when to use, the terminator is removed and a connector of a power
supply module of the BCM type is inserted instead. Meanwhile, where
it is considered that one power supply multiplex communication
cable may be used, a T-shaped branching aditional terminal shown in
FIG. 22 is inserted, but when not in use, a cover is attached to
the module connection side terminal.
[0204] A additional module is higher in universality and can have
variations in accordance with applications where it has a built-in
microcomputer. For example, a additional module which itself has
alarm sound or an alarm lamp, another additional module for an
audio application which includes a reinforced noise filter, a
further additional module which has a burglary prevention function,
a still further additional module which has a function of an engine
starter and so forth may be available.
[0205] An internal block diagram of a additional module which
includes one composite multiplex communication line is shown in
FIG. 23. The additional module shown is much different from that of
the DDM or the like in that it has a built-in microcomputer. Since
the module for extension employs a microcomputer, it is programmed
so that the microcomputer effects all control such as control of
signals from input/output interfaces, signals of a short-circuiting
detection circuit and an interruption circuit. Further, since the
module for extension can be programmed for exclusive use therefor,
finer control is possible. For example, where an additional module
is supplied for an engine starter, a state of a door lock, a
situation of a gear position, a starting situation of the engine
and so forth can be acquired from the BCM or the PCM by data
communication, and cut-off of power supply or the like when the
function as an engine starter is not required can be achieved
readily.
[0206] Description of General Operation
[0207] In the following, operation of the power supply network for
a vehicle is described with reference to flow charts and so forth.
First, in order to facilitate understandings, input and output
information to and from the individual power supply modules are
described with reference to data tables of FIGS. 24 and 26. It is
to be noted that the input and output tables are formed from 4
bytes (2 bytes for the input and 2 bytes for the output) for each
power supply module.
[0208] FIG. 24 shows data tables of data which are fetched as input
signals by the individual power supply modules. Those tables are
written in a freely readable and writable random access memory
(hereinafter referred to as RAM) which is built in the
microcomputer of the BCM. For example, in the case of the BCM, the
table includes the position of the key switch, the position of the
light switch and two kinds of diagnosis information of the room
lamp, and if the ignition key switch is set to the ACC position
(position for accessory power supply), then the bit 15 of the BCM
of the RAM table is set (changed to "1"), but if the ignition key
switch is set to the ON position, then the bit 14 of the BCM is
set.
[0209] In the case of the FIM, the table includes diagnosis
information inputs of the side marker lamps 1a and 6a which are lit
when the light switch 67 in the BCM is positioned to the position
of a POS 627 (lighting of the side marker lamps). It is to be noted
that diagnosis 1 and diagnosis 2 denote the diagnosis signal and
the element diagnosis signal shown in Table 3, and short-circuiting
detection (1) and short-circuiting detection (2) are used to
indicate distinction of one of two power supply multiplex
communication cables which is inputted to the FIM.
[0210] Further, for input information for each of the totaling 10
modules from the BCM to the RIM, 2 bytes are assured, and the
microcomputer built in the BCM confirms, based on the input
information, which one of the switches is operated and controls
supply of power to a load to a module which makes an object of the
control. Further, based on the diagnosis signals, the microcomputer
confirms a load situation of each module or short-circuiting of a
composite multiplex communication cable and effects alarming or
control of power supply cut-off.
[0211] FIG. 25 is a list of output data tables for use for
operation of the electric loads connected to the individual power
supply modules and control of the power supply switching circuits,
control of the cut-off circuits and control of the switching
circuits. The signals set in the table are transmitted to the
individual power supply modules by multiplex communication and used
for operation, and similarly as in the input tables of FIG. 24, for
output information of each of the totaling 10 modules from the BCM
to the RIM, 2 bytes are assured.
[0212] FIG. 26 shows tables for the other control units which
effect multiplex communication separately from the power supply
modules, and data communication is performed between the five units
of the ABS, SDM, air conditioner unit, PCM and navigation unit and
the BCM. Principally, information to be transmitted from the BCM to
the units includes information of the ignition key switch,
information of the light switch and information of the brake
switch. As information from the units, in addition to a "power
supply instruction permission signal" representing "to cut-off
power supplied to the unit", an "operation OK signal" representing
that preparations for operation have been made after power supply
is started and a "trouble occurrence signal" for notification to a
driver that some trouble has occurred with a system controlled by
the unit, information unique to the unit is transmitted to the
BCM.
[0213] Also those data are stored, similarly to the input and
output tables described above, in the RAM built in the
microcomputer of the BCM, and are used as part of control of the
power supply network of the present invention.
[0214] In this manner, in the present embodiment, multiplex
communication is performed between each power supply module and the
BCM and between each control unit and the BCM, and the information
illustrated in FIGS. 24 to 26 is communicated by the multiplex
communication. While details of from where data received by the BCM
have come or to where data to be transmitted by the BCM are to go
are hereinafter described, each of the modules and the units has a
unique name (address) applied thereto so that an object module or
unit is distinguished based on the address.
[0215] Subsequently, how the functions of the present invention
operate when a battery is connected to the vehicle is described in
order with reference to FIG. 27.
[0216] FIG. 27 is a flow chart illustrating operation of the power
supply network after a battery is connected. If a battery is
connected first in step 1, then power is supplied, in step 2, to
the communication ICs and the microcomputers which are the internal
circuits of the BCM and the power supply modules (hereinafter
referred to as LCUs). This power is different from the power to be
used for supply of power to the electric loads and is normally
supplied to the BCM and the LCUs. This power is, for example, in
the BCM, the control circuit power supply 614b.
[0217] When power is supplied to the microcomputer of the BCM,
initialization processing of the microcomputer is performed in step
3. Thprocesses processes which is necessary for any product which
employs a microcomputer, and processes to set the microcomputer to
enable use of the input and output ports of the microcomputer, to
clear the RAM and to make preparations for use of the functions of
the microcomputer. Then in step 4, preparations for transmission of
initialization data to all of the LCUs connected to the BCM are
performed. Here, the switch situations of the power supply
switching circuits of the LCUs are all switched on to make
preparations for power supply to the electric loads and connection
units. In step 5, the BCM fetches a switch input situation and a
trouble situation from any of the LCUs connected thereto. In step
6, the processing in steps 4 and 5 is repeated until it is
completed for all of the LCUs connected to the BCM. Since initial
information necessary to start control is all acquired by
completion of the processing up to step 6, processing execution
start completion is set in step 7. The foregoing is contents of
processing executed without fail when a battery is connected.
[0218] After step 7 is executed, ordinary control in step 8 is
performed. Thprocesses is described with reference to flow charts
shown in FIG. 28 et seq.
[0219] Subsequently, processing when the power supply network is
not used is described. In the present invention, when the system
need not function, in short, when there is no need of supplying
power, in order to minimize discharge of the battery, power supply
to the electric load driving circuits of the LCUs is cut-offed and
the communication ICs and the communication IC 65 and the
microcomputer of the BCM are put into a low current consumption
mode (sleep mode). First, in step 9, it is checked based on the
output tables of FIG. 25 whether or there is an electric load which
is in operation. If some electric load is outputting, then the
processing returns to step 8, in which the processing is repeated.
However, if no electric load is outputting, it is checked in step
10 based on the input tables of FIG. 24 whether or not some
electric load is planned to operate. If some switch is on or a
trouble has occurred, then the processing returns to step 8
similarly. However, if no switch is on or no trouble has occurred,
then in order to cut-off power supply to the electric loads of the
individual LCUs, a signal for switching off a power supply
switching circuit and a switch switching circuit is set to the
output tables in step 11. In step 12, transmission of the set data
is waited, and after the transmission is completed, the
microcomputer enters a sleep mode in step 13. It is to be noted
that, if operation of some switch is performed in this state, then
the microcomputer is released from the sleep mode, and the
processing is repeated again beginning with step 7.
[0220] Description of FIG. 28
[0221] In the following, contents of the ordinary control are
described. FIG. 28 is a routine of a background job processing
(BGJ) which is part of the processing in step 7. This processing
processes which is executed when processing which is hereinafter
described is not executed, and principally executes
diagnosprocesses. In step 14, trouble detection processing for the
power supply multiplex communication cables is performed; in step
15, trouble detection processing of the switching element of the
output interface; and in step 16, trouble detection processing of a
load to be driven is performed. It is to be noted that details are
hereinafter described.
[0222] Description of FIG. 29
[0223] FIG. 29 is a flow chart of communication receive interrupt
for fetching data received by the communication IC 65. The fetched
data here are stored into an input table described with reference
to FIG. 24 or 26.
[0224] First, in step 18, it is checked whether or not the
microcomputer has been in a sleep mode, and if the microcomputer
has been in a sleep mode, then since this signifies that the entire
system is in a low power consumption mode, sleep cancellation
processing is executed in step 19. Here, a sleep cancellation
signal is sent to the communication ICs 52, 70, 77, 84, 102, 109,
120, 131 and 136 of all of the nine LCUs so that processing of
returning the entire system to an ordinary state is executed. If
the microcomputer has been released from a sleep state, then the
processing advances directly to step 20, in which it is
discriminated from address information of a signal received just
now from which LCU or unit the data has been received. If the data
has been received from an LCU, then a data storage address of the
input table of FIG. 24 is calculated in step 21. If the data has
been received from a unit, then a data storage address of the unit
shown in FIG. 26 is calculated similarly. Then, in step 23, the
received data is stored into the object address.
[0225] In this manner, the processing of discriminating, based on
an address of received data, from which module or unit the data has
been received and storing the data into a corresponding table is
the processing of FIG. 29 and is used also for cancellation of a
sleep mode.
[0226] Description of FIG. 30
[0227] FIG. 30 is a processing routine of fixed time interrupt
processing which is started after each fixed period of time. In the
present embodiment, the fixed time interrupt processing is started
after each 1 ms, and almost all processing such as operation of the
individual electric loads and transmission processing performed by
the power supply network is executed here.
[0228] Step 25 processes for interrupting all of the functions of
the power supply network and processes to be used principally in
order to switch processing of the BCM to another unit (for example,
the air conditioner unit). Since thprocesses is not used in
ordinary operation at all, step 26 is executed.
[0229] Step 26 processes for saving, prior to transmission, data
which have been transmitted in the preceding cycle (that is, data
of the transmission table of FIG. 25 at present) temporarily to
another portion of the RAM. Thprocesses is provided in order to
eliminate such a disadvantage that same transmission data which are
transmitted several times in vain occupy the multiplex transmission
lines and disable transmission of other data, and is used to
transmit data only to a destination (LCU) to which the data must be
transmitted.
[0230] Step 27 processes for interrupting the processing of
operating an electric load and is similar to step 25. However, this
step 27 is used to perform self diagnosis.
[0231] Step 28 processes of determining in what priority order a
number of processes should be executed, and in the present
embodiment, thprocesses is executed by three time managements of 5
ms, 10 ms and 50 ms. Principally, those processes for which a
response time after a switch is operated matters are executed after
the short time interval, but those processes with which some delay
does not matter in operation are executed after the long time
interval.
[0232] One of the processes which are executed after each 5 ms is
control of the power window (step 29), and the processes which are
executed after each 10 ms include turn signal control (step 30),
headerlamp lighting control (step 31) and braking lamp lighting
control (step 32). Further, the processes which are executed after
each 50 ms include control of the driver's and passenger's power
seats (step 33) and locking and unlocking control of the door locks
(step 34).
[0233] In step 35, the data stored in step 26 and the data of the
transmission tables set in steps 29 to 34 are compared with each
other, and any LCU address with which same data are detected is
removed. Only those LCU addresses in which different data are
included are extracted, and the output data are transmitted at step
37 so that the object loads are rendered operative.
[0234] Description of FIG. 31
[0235] FIG. 31 illustrates details of the processing in step 37 of
FIG. 30. In step 39, data to be transmitted are extracted from the
address of the transmission table extracted by the comparison in
step 35 of FIG. 30. Then in step 40, the communication destination
address is set to the communication IC 65, and in step 41, the
transmission data are set. Then, in step 42, execution of
transmission is set so that the data are transmitted from the BCM
to the object LCU.
[0236] Based on the data thus transmitted, an electric load of the
LCU operates, and if the diagnosis information or a switch changes
as a result of the operation of the electric load, this is
transmitted as input data from the LCU to the BCM. Mutual
communication is realized by repetition of the sequence of
operations described above.
[0237] In the following, details of the individual contents of
processing are described in order.
[0238] Description of FIG. 32
[0239] First, the trouble detection processing of the power supply
multiplex communication cables in step 14 of the BGJ processing of
FIG. 28 is described. FIG. 32 is a detailed flow chart of the
trouble detection processing. Thprocesses is performed for a module
to which two power supply multiplex communication cables are led
in, and, for another module to which one power supply multiplex
communication cable is led in, only alarming is performed.
[0240] In step 44, a short-circuiting situation of the power supply
multiplex communication cables is read in from the input table of
FIG. 24, and in step 45, it is discriminated whether or not there
is some trouble. If some trouble is detected, then preparations for
transmission of a signal for operating a power supply switching
circuit to a state illustrated in Table 1 to an object LCU are made
in step 47. Then in step 48, in order to notify a driver of the
vehicle that some trouble has occurred, the bit 2 of the
transmission table of FIG. 25 for the IPM which is the "harness
trouble" lamp is set to make preparations for lighting of the alarm
lamp.
[0241] If no trouble is detected in step 45, then data are set to
the transmission table of FIG. 25 in step 49 so that the power
supply switching circuit may be returned to its ordinary state.
Then, in step 50, the bit 2 of the transmission table of FIG. 25
for the IPM which is the "harness trouble" lamp is cleared to make
preparations to extinguish the alarm lamp.
[0242] Description of FIG. 33
[0243] FIG. 33 is a detailed flow chart of step 15 of FIG. 28. Also
in thprocesses, information of the "diagnosis 1" and the "diagnosis
2" of an electric load is read in from the input table of FIG. 24,
and in step 53, the information is compared with the state
indicated in Table 3 to check whether or not some trouble occurs
with an element of an output interface of each of the LCUs and the
units. If there is an LCU or unit which has an element with some
trouble, then the "cut-off output" of the transmission table of
FIG. 25 for the pertaining LCU or unit is set in step 55 to make
preparations to close the cut-off circuit of the pertaining LCU or
unit, and in step 56, in order to notify the driver of the trouble,
the "cut-off output" of the IPM is set to make preparations to
light the alarm lamp. If no trouble is detected in step 54, then
the "interrupt output" of the transmission table of FIG. 25 is
cleared, and in step 58, the alarm lamp of the IPM is
extinguished.
[0244] Description of FIG. 34
[0245] FIG. 34 is a detailed flow chart of step 16 of FIG. 28. Also
here, information of the "diagnosis 1" and the "diagnosis 2" of an
electric load is read in from the input table of FIG. 24, and in
step 61, the information is compared with the state indicated in
Table 3 to check whether or not some trouble occurs with a load to
be driven. If some trouble is detected in this step, then the
"output cut-off" is set to the pertaining control process in step
63 to stop driving of the load. Then, in step 64, it is checked
whether or not the information coincides with the situation of
Table 3, and in order to notify the driver of the trouble, the
"disconnection occurrence" or the "short-circuiting occurrence" of
the IPM is set to make preparations to light the alarm lamp. If no
trouble is detected in step 62, then the "output cut-off" is
cleared to the pertaining control process, and in step 66, the
alarm lamp is extinguished.
[0246] Description of FIG. 35
[0247] FIG. 35 is a detailed flow chart of the power window
(hereinafter referred to as P/W) in step 29 of FIG. 30. In step 67,
it is checked whether or not there is an output cut-off request.
This is used to stop, when the "output cut-off" is set in step 63
of FIG. 34 as described above, all of the operation of the P/W in
step 77. Accordingly, this is not set in ordinary operation at
all.
[0248] First, contents of control of the driver's seat P/W are
described. In step 68, the input table for the DDM is checked, and
in step 69, it is confirmed whether or not the DOWN switch for the
P/W is on. If the DOWN switch for the P/W is on, then the P/W DOWN
of the transmission table for the DDM is set in step 72 to make
preparations to voll down the window. If the DOWN switch of the P/W
is off in step 69, then it is confirmed now in step 70 whether or
not the UP switch is on. If the UP switch is on, then the UP is set
now similarly to make preparations to voll up the window. If the UP
switch is off also in step 70, since this signifies that no switch
is operated, the portions of the transmission table for the DDM
which relate to the P/W are cleared in step 71.
[0249] While steps 74, 75 and 76 represent contents of processing
of the PDM of the passenger's seat, the RRDM which is the rear seat
on the right side and the RLDM which is the rear seat on the left
side, respectively, they are basically same as those of the
DDM.
[0250] Description of FIG. 36
[0251] FIG. 36 is a detailed flow chart of the turn signal control
in step 30 of FIG. 30, and this control processes of lighting the
turn indicator for the right or left turn.
[0252] The processing in steps 78 and 86 is used for the same
object as that of the P/W control described hereinabove, and
accordingly, description of the same is omitted.
[0253] First in step 79, the input table for the BCM is conformed,
and in step 80, it is checked whether or not the turn switch for
the right (RH) turn is on. If the turn switch for the right (RH)
turn is on, then processing for causing the right turn indicating
lamp (TRN-R) connected to the FIM and the RIM to blink is performed
in step 84. If the turn switch for the right (RH) turn is off, then
it is checked in step 81 whether or not the turn switch for the
left (LH) turn is on. If the turn switch for the left (LH) turn is
on, then processing of causing the left turn indicating lamp
(TRN-L) connected to the FIM and the RIM to blink is executed in
step 85. If the turn switch for the left (LH) turn is off also in
step 81, then since this signifies that no switch is operated, the
portions of the transmission tables for the FIM and the RIM which
relate to a turn signal are cleared.
[0254] Description of FIG. 37
[0255] FIG. 37 is a detailed flow chart of the headerlamp
(headerlight, hereinafter referred to as HL) control in step 31 of
FIG. 30, and this control involves PWM (pulse width modulation)
control of the lamps for varying the brightness depending upon
whether or not there is a vehicle speed.
[0256] Since the processing in steps 87 and 101 is used for the
same object as that of the P/W control described above, description
of the same is omitted.
[0257] This control is control of lighting the clearance lamps
(side marker lamps, hereinafter referred to as CLs) when the light
switch is positioned to the POS position but lighting the HLs when
the light switch is positioned to the on position.
[0258] First in step 88, the input table for the BCM is checked,
and in step 89, it is checked whether or not the light switch is at
the POS position. If the light switch is at the POS position, then
the CL output of the transmission table for the FIM is set in step
90, and the CL output of the transmission table for the RIM is set
in step 91 to make preparations to light the side marker lamps. If
the light switch is not at the POS position, then the CL output of
the transmission table for the FIM is cleared in step 92, and the
CL output of the transmission table for the RIM is cleared in step
93 to make preparations to extinguish the side marker lamps.
[0259] Then, in step 94, it is checked whether or not the light
switch is at the on position. If the light switch is at the on
position, then in step 96, the HL output of the transmission table
for the FIM is set and data 20% which is duty information of the
PWM to the communication IC 52 is set simultaneously. Then in step
97, it is checked whether or not there is a vehicle speed, and if
some vehicle speed is detected, then data 100% which is duty
information of the PWM to the communication IC 52 is set in step
98. If the light switch is at the off position in step 94, then the
HL output of the transmission table for the FIM is cleared in step
99, and the CL output of the transmission table for the RIM is
cleared in step 100 to make preparations to extinguish the
headerlamps and the side marker lamps.
[0260] Description of FIG. 38
[0261] FIG. 38 is a detailed flow chart of the braking lamp control
for lighting the stop lamps in step 32 of FIG. 30.
[0262] Since the processing in steps 102 and 107 is used for the
same object as that of the P/W control described above, description
of the same is omitted.
[0263] In FIG. 103, the input table for the BCM is checked, and if
the brake switch is on in step 104, then the STOP output of the
transmission table for the RIM is set in step 105 to complete
preparations to light the brake lamps. If the switch is off in step
104, then the STOP output of the transmission table for the RIM is
cleared in step 106 to complete preparations to extinguish the
brake lamps.
[0264] Description of FIG. 39
[0265] FIG. 39 is a detailed flow chart of the control of locking
or unlocking the door lock of the automobile in step 34 of FIG.
30.
[0266] Since the processing in steps 108 and 120 is used for the
same object as that of the P/W control described above, description
of the same is omitted.
[0267] In step 109, the input table for the DDM is checked, and
first in step 110, it is checked whether or not a switch for
locking the door is operated. If the switch for locking the door is
operated, then the "door LK" of the transmission table for the DDM
is set and the "door UL" is cleared to set the door lock output in
step 111. Then in step 112, it is waited that locking of the door
is completed while confirming the "door lock detection" signal of
the input table. If the switch for locking the door is not operated
in step 110, then it is checked in step 113 whether or not the
switch for unlocking the door is operated. If the switch for
unlocking the door is operated, then the "door LK" of the
transmission table for the DDM is cleared and the "door LK" is set
to set the door unlock output. Then, similarly in step 115, it is
waited that unlocking of the door is completed while confirming the
"door lock detection" signal of the input table.
[0268] If none of the two switches is operated, then the "door LK"
and the "door UL" of the transmission table for the DDM are cleared
to clear the door output.
[0269] Thereafter, door lock control of the passenger's seat in
step 117, door lock control of the rear seat on the right side in
step 118 and door lock control of the rear seat on the left side in
step 119 are executed. Since the contents of the controls are same
as those described above, description of the same is omitted.
[0270] Description of FIG. 40
[0271] FIG. 40 is a detailed flow chart of control for moving the
reclining and sliding positions of the seats of the driver's seat
and the passenger's seat in step 33 of FIG. 30.
[0272] Since the processing in steps 121 and 134 is used for the
same object as that of the P/W control described above, description
of the same is omitted.
[0273] First in step 122, the input table for the DSM is checked,
and in step 123, it is checked whether or not the switch for moving
the reclining apparatus forwardly is on. If the switch is on, then
the "reclining forward" of the transmission table for the DSM is
set and the "reclining backward" is cleared in step 124 to make
preparations for operation of the motor to tilt the reclining
position forwardly. If the switch for moving the reclining position
is not on in step 123, then it is checked in step 125 whether or
not the switch for moving the reclining position backwardly is on.
If the switch is on, then the "reclining forward" of the
transmission table for the DSM is cleared and the "reclining
backward" is set to make preparations for operation of the motor so
that the reclining position may be tilted backwardly. If none of
the two switches is operated, then the "reclining forward" and the
"reclining backward" of the transmission table for the DSM are
cleared in step 127 so that the motor for the reclining operation
may be stopped.
[0274] Subsequently, a method of moving the sliding position of a
seat is described.
[0275] First in step 128, it is checked whether or not the switch
for moving the sliding position forwardly is on. If the switch is
on, then the "slide forward" of the transmission table for the DSM
is set and the "slide backward" is cleared in step 129 to make
preparations for operating the motor so that the slide position may
be moved forwardly. If the switch for moving the sliding position
forwardly is not on in step 128, then it is checked in step 130
whether or not the switch for moving the sliding position
backwardly is on. If the switch is on, then the "slide forward" of
the transmission table for the DSM is cleared and the "slide
backward" is set to make preparations for operating the motor so
that the sliding position may be moved backwardly. If none of the
two switches is operated, then the "slide forward" and the "slide
backward" of the transmission table for the DMS are cleared in step
132 so that the motor for the sliding operation may be stopped.
[0276] Step 133 executes the processing in steps 122 to 132 for the
passenger's seat, and since this processing is same in control,
description of the same is omitted.
[0277] Description of FIG. 41
[0278] FIG. 41 is a detailed flow chart of the control of unlocking
the trunk in step 34A of FIG. 30.
[0279] Since the processing in steps 135 and 140 is used for the
same object as that of the P/W control described hereinabove,
description of the same is omitted.
[0280] First in step 136, the input table for the IPM is checked,
and if the "trunk open" signal is set in step 137, then the "trunk
output" of the transmission table for the RIM is set in step 138 to
make preparations to supply power to the motor for unlocking the
trunk. If the "trunk open" signal is not set in step 137, then the
"trunk output" of the transmission table for the RIM is cleared in
step 139 to make preparations to stop the power to the motor for
unlocking the trunk, thereby ending the processing.
[0281] In the following, the communication control system used in
the present embodiment is described in detail with reference to
FIGS. 42 to 60 and Tables 4 to 10.
[0282] The I/O communication IC effects transmission of a digital
input signal via a communication bus to a control module which
includes a CPU. Further, the I/O communication IC effects on-off
control of a digital equipment via the communication bus from the
control module. By the way, a plurality of I/O communication ICs
are connected to the communication bus. Therefore, each of the I/O
communication ICs has such functions as described below which
prevent interference of data communicated between the I/O
communication IC and the control module. First, the communication
ICs connected to the communication bus have respective unique
numbers which do not overlap with each other, and transmission data
include input/output data and the unique number of the apparatus
which transmits the data. Second, each of the I/O communication ICs
has a communication bus supervision function to prevent collision
between data from a plurality of apparatus, and effects
transmission when the communication bus is not used by any other
communication IC. Further, if a plurality of units start their
communication, then based on priority order data included in data,
that unit which exhibits the highest priority order is allowed to
transmit data to the communication bus.
[0283] The I/O communication IC effects transmission in the
following two cases. One of the two cases is that a digital input
signal connected to it exhibits a variation, and the other is that
a transmission request is received from the control module.
[0284] Further, the I/O communication IC receives data and sets the
data to the output ports only when data on the transmission bus are
analyzed and the data are destined for the I/O communication
IC.
[0285] A circuit construction of the I/O communication IC is shown
in FIG. 42. Functions of the I/O communication IC are divided into
transmission, reception and transmission-reception timing
controlling functions. First, a method by which the I/O
communication IC transmits an input signal is described.
[0286] In transmission, if a transmission request is received, then
the I/O communication IC confirms that the communication bus is not
used by any other unit and transmits digital data to the
communication bus in accordance with a prescribed format. The data
format includes header data, digital input data and data check
data. If a transmission request is received, then an input signal
is set from a digital I/O port to an I/O register. If the
communication bus can be used, then data are set to a Tx register
in order of the header register, receive address register, transmit
address register, I/O register and CRC generator. The data set to
the Tx register are inputted to a VPW generator, by which they are
variable pulse width (VPW) modulated, and are then transmitted to
the communication bus. The VPW modulation method is a method
wherein digital data of "1" and "0" are transmitted with two
different pulse widths and two different voltage levels.
[0287] According to this modulation method, when data being
transmitted at present and the next bit are the same data, both of
the voltage level and the pulse width are varied, but when they are
different, only the voltage level is varied.
[0288] Here, in the header register, characters of following data
such as priority order data of the unit are set in advance. In the
receive address register, address data (the apparatus number) of
another unit which is to receive data transmitted is set, and in
the transmit address register, the transmission apparatus number,
that is, the apparatus number of the unit, is set. The CRC
generator is a circuit which performs CRC (Cyclic Redundancy Check)
from the header register to the I/O register. Here, the CRC
calculation is one of methods of error detection which are
performed in data transmission.
[0289] In the following, a method by which the I/O communication IC
receives data from the communication bus and set the data to the
output port is described.
[0290] Data on the communication bus are inputted to a VPW decoder
after noise components are removed therefrom by a digital
filter.
[0291] The VPW decoder converts, reversely to the VPW generator, a
VPW modulated signal to digital data of "1" and "0".
[0292] The digital data obtained by the conversion are inputted to
an Rx register, and contents of the headerer register and the
receive register are compared with the apparatus number and so
forth of the I/O communication IC to discriminate whether or not
the data on the communication bus have been destined for the I/O
communication IC.
[0293] If it is discriminated that the data on the communication
bus are destined for any other unit, then the following reception
operation is not performed. When the data on the communication bus
are destined for the I/O communication IC, the following Rx
register is set to the I/O register. Then, when the OK output of
the CRC check circuit becomes true, the contents of the I/O port
are set to the output port. When the OK output of the CRC check
circuit is false, a receive error is outputted to notify the
transmission side that a receive error has occurred.
[0294] Here, the transmission and reception timing control of the
communication IC is performed by a scheduler.
[0295] The scheduler is formed from a status registor, a stage
counter, a byte counter and so forth. The status register is a
register which represents a status of the communication IC
(transmitting, receiving, transmission-reception error or the
like). The stage counter is a register which represents a time
series-state during transmission or reception.
[0296] Here, when data are to be transmitted to the communication
bus, in addition to the data from the header data to the CRC data,
a special signal different from a data signal (VPW signal)
representative of a start and an end is added. The start signal is
called SOF (Start Of Frame), and the end signal is called EOD (End
Of Data).
[0297] The stage counter is a register which represents one of the
states of the SOF, data, EOD and no data.
[0298] The byte counter is a counter which represents which data
the transmit or receive data (from the header data to the CRC data)
are.
[0299] In addition, the communication IC circuit includes a clock
generator which generates a signal. Here, signal lines connected to
the communication IC include, in addition to the communication bus
line and the digital input/output signal line, apparatus number,
priority order signal and input signal number (or output signal
number) lines.
[0300] Basic operation of the communication IC has been described
in outline so far. The communication IC has, in addition to the
operation for ordinary transmission and reception, a sleep
operation mode in which those circuits which operate in response to
a clock signal are stopped to suppress the power consumption to a
level substantially equal to leak currents of the semiconductor
elements. Transition into the sleep mode occurs depending upon
transmission data from the communication bus or when the digital
signal does not exhibit a variation for more than a fixed period of
time.
[0301] Transition from the sleep mode to the ordinary operation
mode occurs when communication data are sent to the communication
bus or when a variation occurs in the input signal.
[0302] In the following, detailed operation of the communication IC
are described.
[0303] Communication ICs are divided into two kinds including an
I/O communication IC and a C/U (Control Unit) communication IC. The
I/O communication IC effects interfacing between a digital
input/output and a communication bus, and C/U communication IC
effects interfacing between a communication bus and a CPU.
[0304] Both communication ICs have apparatus addresses (apparatus
numbers) which do not overlap with each other and effect data
communication with each other. An example of addresses of the
communication ICs connected to the communication bus is indicated
in Table 4. Here, the example is shown wherein the address is
indicated by 1 byte and the upper 4 bits represent an address for
identification of a control function while the lower 4 bits
represent a number for identification of a communication IC in the
same control system.
[0305] Here, any address whose number of the lower 4 bits is 0
represents a C/U (Control Unit) communication IC. The unit whose
number of this is 0 has a function which can work data of the same
control system. In the other units, the bit construction of data
transmitted or received and the digital input/output ports
correspond in a one-by-one corresponding relationship to each
other, and the units have no editing working function.
4TABLE 4 Physical Address Table 1
[0306]
5TABLE 4 Input/Output Apparatus Allocation Table I/O # Signal name
(input) Signal name (out put) BCM(Address 30) 00 Switch switching
(2) Switch switching (2) 01 Switch switching (1) Switch switching
(1) 02 Power supply Power supply switching (2) switching (2) 03
Power supply Power supply switching (1) switching (1) cut-off
output 04 05 Lamp diagnosis 2 Lamp output 06 Lamp diagnosis 1 07 08
09 Turn SW LH 10 Turn SW RH 11 Light SW ON 12 Light SW 1 step 13
Key SW ST 14 Key SW ON 15 Key SW ACC BCM(Address 34) 00
Short-circuiting detection 01 Interrupted state 02 03 04 Cut-off
output 05 06 07 Brake diagnosis Short-circuiting occurrence 08 Door
diagnosis Disconnection occurrence 09 CL diagnosis Harness trouble
10 HD diagnosis 11 TRN-L diagnosis TRN-L lamp 12 TRN-R diagnosis
TRN-R lamp 13 Brake lamp 14 Brake SW CL lamp 15 Trunk open HD lamp
BCM(Address 39) 00 Short-circuiting Switch switching (2) detection
(2) 01 Short-circuiting Switch switching (1) detection (1) 02 Power
supply Power supply switching (2) switching (2) 03 Power supply
Power supply switching (1) switching (1) cut-off output 04
Interrupted state 05 HORN output 06 HORN diagnosis 2 HL output 07
HORN diagnosis 1 TRN-R output 08 HL diagnosis 2 TRN-L output 09 HL
diagnosis 1 10 TRN-R diagnosis 2 11 TRN-R diagnosis 1 CL output 12
TRN-L diagnosis 2 13 TRN-L diagnosis 1 14 CL diagnosis 2 15 CL
diagnosis 1
[0307] In the address of the C/U communication IC shown in Table 4,
1x: PCM (engine control system), 2x: ABS (brake control system),
3x: BCM (body control system, 4x: SDM (Air Bag System), 5x: A/C
(air conditioner), 6x: navigation system), and 7x: beacon.
Meanwhile, in the address of the I/O communication IC of the BCM
system, 30: BCM (Body Control Module), 31: PDM (Passenger Door
Module), 32: DDM (Driver Door Module), 33: RRDM (Rear Right Door
Module), 34: IPM (Instrument Panel Module), 35: DSM (Driver Seat
Module), 36: RIM (Rear Integrated Module), 37: PDM (Passenger Door
Module), 38: RLDM (Rear Left Door Module, and 39: FIM (Front
Integration Module).
[0308] Further, an example of input signals and output device
signals of the BCM (body control system) connected to the BCM, IPM
and FIM is shown.
[0309] By such addressing, an outline of functions of an apparatus
can be discriminated from its address, and understanding of the
functions, analysis of an error and so forth can be performed
readily.
[0310] Here, an example of operation when the left turn signal is
turned on is described.
[0311] If the turn SW LH at 09 connected to the BCM at the address
30 is put into an on-state (when the left turn signal is turned
on), then the turn SW LH processing program at 09 incorporated in
the BCM is started. This processing program is transmitted from the
BCM of the data at the output number 11 at the address 34 by which
the TRN-L lamp is lit to the IPM, and also the output 08 of the FIM
at the address 39 is transmitted from the BCM to the FIM.
[0312] In particular, if the driver operates a winker knob on a
steering column apparatus to turn on the left turn signal switch,
then one of the turn signal lamps on the front face of the body
blinks and also the left turn signal lamp on the instrument panel
blinks.
[0313] Next, power supplying operation of the ABS and the PCM is
described.
[0314] The output 00 of the communication IC of the FIM is
connected to the switch switching (2), and the output 01 is
connected to the switch switching (1).
[0315] Meanwhile, the switch switching (2) performs on/off control
of the power supply line to the ABS, and the switch switching (1)
performs on/off control of the power supply line to the PCM.
[0316] In particular, supply of power to the ABS and the PCM is
performed when the output signal of the FIM is 00 and 01.
Meanwhile, on/off of the output signals 00 and 01 of the FIM is
performed by the BCM.
[0317] Therefore, the CPU of the BCM can perform power supply
control to the ABS and the PCM grasping states of apparatus
connected to the system.
[0318] Subsequently, the data format transmitted between the
communication ICs is described.
[0319] FIG. 43 shows different kinds of the data format
transmitted.
[0320] The transmission data format has six kinds of 1.
initialization, 2. ordinary transmission, 3. diagnosis request, 4.
diagnosis response, 5. data transmission request, and 6. sleep
start.
[0321] Here, the common format among the formats includes the SOF,
receive address, transmit address, format ID, data, CRC data and
EOD.
[0322] The directions of input/output ports of a communication IC
can be set arbitrarily. Therefore, the initialization format
performs setting input/outputs from a CPU to an I/O communication
IC by inputting to or outputting from the ports.
[0323] It is to be noted that, when power supply to a communication
IC is on, the ports of the communication are set to input ports.
Setting data are bit data corresponding in a one-by-one
corresponding relationship to the individual ports, and "1"
represents an output port, and "0" represents an input port.
[0324] Transmission data from a CPU to an I/O communication IC upon
ordinary transmission are output data to the I/O ports
corresponding in a one-by-one corresponding relationship to the
individual ports.
[0325] Here, data to the input ports are ignored.
[0326] Meanwhile, transmission data from the I/O communication IC
to the CPU are input data to the I/O communication IC, and data of
the output ports are data being outputted at present.
[0327] From this, confirmation of output data can be performed.
[0328] The diagnosis request and the diagnosis response are based
on the SAE1979 diagnostic message format.
[0329] The data transmission request is transmitted from the CPU to
the I/O communication IC and has no part for data.
[0330] Also the sleep start is transmitted from the CPU to the I/O
communication IC. If this data is received by the I/O communication
IC, then the I/O communication IC stops a clock signal and enters a
low power consumption mode. It is to be noted that data
transmission between CPUs is different from transmission between an
I/O communication IC and a CPU, and contents of data of individual
bits are determined uniquely between different CPUs.
[0331] Subsequently, variation of the operation state of a
communication IC is described.
[0332] FIG. 44 shows a state transition table of a communication
IC.
[0333] The communication IC has the following 9 different
states.
[0334] The states are: 1. no transmit/receive data, 2. data being
transmitted, 3. start of data transmission, 4. waiting for
re-sending, 5. production of transmission data, 6. data being
received, 7. data transmission by the other modes, 8. retrieval of
receive data, and 9. sleep.
[0335] The state 1 is a state wherein no transmission data is
present on the communication bus and there is no data to be
transmitted and consequently a change is waited.
[0336] If input data exhibits a variation, then the state 5 is
entered and preparations for transmission are performed, and then
the state 3 is entered and data transmission is started.
[0337] In the transmission, SOF header data is transmitted to the
communication bus.
[0338] Here, if also another communication IC transmits
simultaneously, then if the priority order data in the header data
from the first-mentioned communication IC is higher than that from
the second communication IC, the first communication IC continues
its transmission and enters the state 2. data being
transmitted.
[0339] On the contrary if the priority order data is lower, then
the first-mentioned communication IC enters the state 4. waiting
for re-sending. When the state of waiting for re-sending is
entered, the communication IC waits until the second-mentioned
communication IC completes its transmission, and repeats the
transmission starting procedure.
[0340] In reception, if data appears on the communication bus, then
the communication IC first receives the SOF, header data and
receive address data. Then, if the receive data coincides with the
address data of the communication IC itself, then the communication
IC receives also following data. Then, if the result of CRC
checking is OK, then the communication IC sets the received data to
a predetermined port. However, if the receive address data is
different from the address of the communication IC itself, the
communication IC stops its receiving operation ignoring following
data.
[0341] Here, when the receive data is the sleep start data,
generation of the clock signal is stopped, and the low power
consumption mode is entered.
[0342] Transition from the sleep mode to the ordinary mode is
performed either when a variation occurs with the input signal or
when data appears on the communication bus.
[0343] Subsequently, an example of transmission of data between the
BCM, DDM and PDM is described.
[0344] FIG. 45 is a time chart of the data transmission.
[0345] Here, the addresses of the individual units are: 30 for the
BCM; 31 for the PSDM; and 32 for the DDM. The priority data are the
same as the address data, and the priority order is given in a
descending order of the address number.
[0346] The state numbers and the transmission data generation
signal illustrated in FIG. 45 are those of the DDM. The data 1 on
the communication bus is data when a transmission request is
produced by the DDM and data is transmitted from the DDM to the
BCM. The data 2 is data transmitted from the BCM to the PDM, and is
not received by the DDM. The data 3 is data transmitted from the
BCM to the DDM and received by the DDM.
[0347] When DDM transmission data is generated during the reception
by the DDM or when, though not illustrated in FIG. 45, another
transmission request is produced by the SDM, the DDM starts its
transmission after waiting until completion of the reception of the
data 3, but also the SDM starts transmission simultaneously.
[0348] If it is discriminated, after starting of the transmission,
that the SDM has a higher priority during transmission of the
header data, then the DDM stops its transmission and waits for
re-sending.
[0349] Here, the data 4 is transmission data from the SDM to the
BCM.
[0350] The data 5 is transmission data from the DDM, which is
waiting for re-sending, to the BCM.
[0351] The foregoing is transmission/reception operation of data by
a communication IC.
[0352] FIG. 46 shows a circuit portion of an I/O communication IC
which relates to transmission of data. FIG. 47 is a time chart of
the circuit portion.
[0353] When the I/O communication IC is in a communication enabled
state, if a transmission start signal is generated, then data is
transmitted to the communication bus in accordance with a
prescribed time sequence.
[0354] When the I/O communication sequence is in a communication
enabled state, a communication bus busy flag of the status register
is in an off state. Transmission is started when a transmission
request flag of the status register changes to an on-state.
[0355] If a transmission start signal is inputted, then the stage
counter, byte counter and bit counter of the schedule counter are
rendered operative.
[0356] An output of the stage counter is inputted to the VPW
generator. The stage counter outputs a stage clock (S.cndot.Clock)
signal, a data clock (Clock.cndot.Out) and transmission data
(Data.cndot.Out) in synchronism with a clock signal .phi. 2.
[0357] The VPW generator outputs an SOF signal, data and an EOD
signal in this order.
[0358] Based on the calculated value of the byte counter, the
header register, receive address register, transmission address
register, I/O register and CRC generator are successively selected
in this order, and the data are set to the transmission register
(Tx register).
[0359] The data of the Tx register is inputted to and VPW
multiplexed by the VPW generator in response to the Clock.cndot.Out
signal of the VPW generator and transmitted to the communication
bus.
[0360] Here, the number of bytes of the I/O registor is 4 bytes as
an example.
[0361] The bit clock signal for the transmission data is controlled
by the bit counter. Here, the values of the headerer register,
receive address and transmission address registers are set to
initial state values from an external input signal or from some
other communication IC.
[0362] Further, the data of the CRC generator are calculated with
data from the headerer data to the I/O data.
[0363] A detailed circuit of the CRC generator is shown in FIG.
53.
[0364] A circuit construction of the schedule counter is shown in
FIG. 48. This circuit is formed from a bit counter, a byte counter
and a stage counter.
[0365] The bit counter is a circuit which divides the frequency of
the data clock signal of the VPW to 1/8.
[0366] The byte counter is a shift register which receives the bit
counter as a clock signal thereto, and outputs of the byte counter
are connected to select terminals of the registers in an order of
transmission thereof.
[0367] The stage register is a shift register which receives the
stage clock signal of the VPW generator or the CRC output as a
clock signal thereto, and an output of the stage register is
connected to the VPW generator. A time chart of the schedule
counter described above is illustrated in FIG. 49.
[0368] Subsequently, the VPW generator is described.
[0369] FIG. 50 shows a circuit construction of the VPW generator,
and FIG. 51 is a time chart of the VPW generator.
[0370] The VPW generator is a circuit which generates signals of
several different pulse widths to be used by the different
communication ICs. The pulse width to be generated is different
among the SOF, data, EOD and so forth.
[0371] The pulse signal is generated by setting a suitable value to
an 8-bit presettable down counter based on output data of the stage
counter of the scheduler.
[0372] FIG. 52 is a diagram showing a circuit construction of a
generation ROM for one bit, and Table 5 is a setting table for the
individual bits.
6TABLE 5 Signal name Pulse value Symbol Set value name Active
Passive (.mu.s) 2.sup.0 2.sup.1 2.sup.2 2.sup.3 2.sup.4 2.sup.5 TV1
"1" "0" 64 8 0 0 0 1 0 0 TV2 "0" "1" 128 16 0 0 0 0 1 0 TV3 SOF EOD
200 25 1 0 1 1 0 0 TV4 EOF 280 35 1 1 0 0 0 1 TV5 BLK IFS 300 38 0
1 1 0 0 1
[0373] As seen from Table 5, nine different pulse signals which are
used in the present communication IC can be outputted from the VPW
generator.
[0374] Subsequently, the CRC generator is described.
[0375] The CRC check codes used in the present communication IC are
formed from 8 bits.
[0376] FIG. 53 is a circuit diagram showing a construction of the
CRC generator, and Table 6 shows a time table of the CRC
generator.
7 TABLE 6 stage Bit Start 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
18 19 20 21 22 23 24 CRC DATA HEX F2 01 83 37 DATA BIN 1 1 1 1 0 0
1 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 1 1 X.sub.8 1 0 0 0 0 1 1 0 1 1 0 0
0 1 1 1 0 0 1 0 1 0 1 1 0 X.sub.0 1 0 0 0 0 1 1 0 1 1 0 0 0 1 1 1 0
1 0 1 0 1 0 0 0 1 X.sub.1 1 1 0 0 0 0 1 1 0 1 1 0 0 0 1 1 1 0 1 0 1
0 1 0 0 1 X.sub.2 1 1 0 0 1 1 1 0 1 1 1 0 1 1 0 1 0 0 0 0 0 0 0 1 0
X.sub.3 1 1 1 1 0 1 0 1 0 1 1 1 1 1 0 0 0 0 0 1 0 1 0 0 1 0 X.sub.4
1 1 1 1 1 1 0 0 0 1 1 1 1 0 0 1 0 1 0 1 1 1 1 0 0 1 X.sub.5 1 1 1 1
1 1 1 0 0 0 1 1 1 1 0 0 1 0 1 0 1 1 1 1 0 1 X.sub.6 1 1 1 1 1 1 1 1
0 0 0 1 1 1 1 0 0 1 0 1 0 1 1 1 1 0 X.sub.7 1 1 1 1 1 1 1 1 1 0 0 0
1 1 1 1 0 0 1 0 1 0 1 1 1 0
[0377] The CRC generator circuit is constructed such that exclusive
OR circuits are provided for input terminals of the second, third
and fourth bits of an 8-bit shift register and one of two input
terminals of each of the exclusive OR circuits is connected to an
output of the preceding stage while the other input terminal is
connected to an exclusive OR circuit for an output of the seventh
bit and input data.
[0378] The CRC generator circuit having the circuit construction
described above can produce a CRC check code.
[0379] Table 6 represents a manner of state variations of the bits
by input data and a clock signal.
[0380] The last data is transmitted to the Tx register following
I/O data.
[0381] Next, Table 7 illustrates contents of the bits of the status
register which effects management of the communication IC together
with the schedule counter.
8 TABLE 7 Symbol # name Bit name Contents of bit 0 Buz Bus busy
Data present on flag communication bus 1 RXR Receive Target address
data request flag coincides with my address 2 TXR Transmit I/O data
varies request flag 3 RXB Receive busy Busy with reception flag 4
TXB Transmit busy Busy with transmission flag 5 RXE receive CRC
error present error 6 TXE Transmit Transmission failed error
because of low priority 7 SLP Sleep Sleeping
[0382] The bus busy flag exhibits an on-state when data are present
on the communication bus.
[0383] The receive request flag is put into an on-state when
receive address data of receive data coincides with the address of
the communication IC. The transmit request flag is put into an
on-state either when input data varies or when transmit request
data is received.
[0384] The receive busy flag exhibits an on-state when data is
being received.
[0385] The transmit busy flag exhibits an on-state when data is
being transmitted.
[0386] The receive error flag exhibits an on-state when the CRC
check of received data is NG.
[0387] The transmit error flag is put into an on-state when, after
transmission is started, another communication IC which is higher
in priority simultaneously starts communication on the
communication bus.
[0388] The sleep flag is put into an on-state when sleep start data
is received, and a clock signal is stopped.
[0389] Table 8 illustrates an example of data ID for identification
among the different formats of data transmitted and received shown
in FIG. 43.
9TABLE 8 Bits Data ID 0000 Initialization 0001 Ordinary transfer
0010 Diagnosis request 0011 Diagnosis response 0100 Data
transmission request 0101 Sleep start 0110 0111
[0390] The forgoing is operation of the circuit regarding
transmission.
[0391] Subsequently, a circuit regarding reception is described.
FIG. 54 shows a circuit construction regarding reception, and FIG.
55 shows a time chart of the circuit.
[0392] Also reception is managed by a schedule counter similarly to
transmission.
[0393] If a receive start signal is inputted when reception is
possible (the RXR is on), then the schedule counter and the VPW
decoder are reset.
[0394] If it is discriminated by the VPW decoder that a signal on
the communication bus is an SOF signal, then the bit counter and
the byte counter start their operation.
[0395] The VPW decoder effects discrimination between 1" and "0"
signals of a VPW modulated data signal.
[0396] Data obtained by the discrimination is inputted to a receive
address checker, a CRC checker and an Rx register.
[0397] If the receive address data of the receive data is data
destined for the communication IC, then the data inputted to the Rx
register is transferred in units of one byte to the I/O
register.
[0398] Bit discrimination in this instance is performed with VPW
data. Meanwhile, byte discrimination is performed by the byte
counter.
[0399] If the I/O data come to an end, then data checking is
performed by the CRC checker, and when a result of the data
checking is OK, the value of the I/O register is transferred to the
I/O port.
[0400] If an error is detected, then the value of the I/O register
is not transported to the I/O port, but the receive error flag of
the status register is changed to on.
[0401] FIG. 55 is a time chart illustrating the manner described
above.
[0402] FIG. 56 shows a circuit construction of the VPW decoder and
FIG. 57 shows a time chart of the VPW decoder.
[0403] Receive data is inputted to a D-type flip-flop in response
to a clock signal .phi. 2.
[0404] The input and the output of the flip-flop are inputted to an
exclusive OR circuit to detect a variation of the receive data to
produce a bit clock. The pulse width of the data is measured by a
binary counter which is reset by the bit clock and counts with the
clock signal .phi. 2.
[0405] Based on the thus measured pulse width and a signal of the
stage counter, the SOF, data, the EOD and the IFS are
discriminated.
[0406] Discrimination of the data between "1" and "0" is performed
such that, when the pulse width exhibits no variation, the
preceding data of "1" or "0" is reversed, but when the pulse
exhibits a variation, the value of the data is not varied.
[0407] The initial value level lowes pnds to the value of initial
data.
[0408] Table 9 shows a truth table when the voltage level and the
pulse width are classified into two values.
[0409] When the data relationships between the voltage and the time
of the input signal are put in order using the following
definitions:
[0410] Tv[0]=Tv1
[0411] Tv[1]=Tv2
[0412] Vout[0]=Vlow
[0413] Vout[1]=Vhigh
[0414] the following table is obtained.
10 TABLE 9 Input Voltage Time Output 0 0 0 0 1 1 1 0 1 1 1 0
[0415] FIG. 58 shows a circuit construction of the CRC checker and
Table 10 shows a time table of the CRC checker.
11TABLE 10 2
[0416] The CRC checker has a circuit construction wherein an AND
circuit for discrimination of OK is added to a CRC generator.
[0417] The discrimination output is OK if the last data including
CRC data is C4 in hexadecimal value.
[0418] FIGS. 59 and 60 show a circuit construction and a time chart
of a clock generator for generating the clock signals of the
communication IC.
[0419] An oscillator having two terminals is connected to the input
and output terminals of an inverter so that it may oscillate to
effect waveform shaping to output clock signals .phi. 1 and .phi. 2
having different phases from each other.
[0420] Stopping or starting of the oscillation is performed with a
sleep flag output of the stage register.
[0421] A concrete example of input/output control of the power
supply modules described above is described in more detail in
comparison with the prior art.
[0422] FIG. 61 shows a system diagram of an engine and driving
system controller PCM (this basically has a same construction as
that of the PCM described hereinabove, but since inputs and outputs
are indicated concretely in accordance with an actual example, this
is described with new reference symbols applied thereto) of a
vehicle to which a power supply network of the present invention is
applied. A control module 1000 receives various sensor signals
necessary for control of the engine and the driving system (in the
present embodiment, the automatic transmission) and outputs driving
signals for various actuators in accordance with a predetermined
control method. An air flow sensor 1001 measures an intake air flow
amount of the engine, converts it into an electric signal and
outputs the electric signal. A water temperature sensor 1002
detects the temperature of the engine coolant, converts it into an
electric signal and outputs the electric signal. An O2 sensor 1003
detects the concentration of oxygen in exhaust gas, converts it
into an electric signal and outputs the electric signal. A knock
sensor 1005 detects a knocking state of the engine, converts it
into an electric signal and outputs the electric signal. An exhaust
gas temperature sensor 1006 detects the temperature of a catalyzer
for exhaust gas purification, converts it into an electric signal
and outputs the electric signal. An A/T fluid temperature sensor
1007 detects the temperature of control fluid of the A/T (Automatic
transmission), converts it into an electric signal and outputs the
electric signal. A crank angle sensor 1008 detects a crank angle
and outputs a pulse signal, for example, for each one degree. A
vehicle speed sensor 1008A outputs a pulse signal corresponding to
rotation of a wheel. A power steering switch 1009 detects a rise of
the hydraulic pressure when the power steering apparatus is driven.
This switch is provided to increase the idling speed of the engine
when the power steering apparatus is used upon idling. A shift
inhibitor switch 1010 is a switch provided corresponding to a
position of a shift control lever of the A/T and detects a shift
position. An ignition system 1011 includes an ignition plug and an
ignition coil of the engine and ignites the ignition plug in
response to an instruction of the PCM 1000. An injector 1012 is a
fuel injection valve for injecting fuel in response to an
instruction of the PCM 1000. An A/T solenoid valve 1013 controls
the hydraulic fluid pressure of the AT in response to an
instruction of the PCM 1000 to effect shift control. A cooling fan
1014 is a fan for cooling the radiator and operates in response to
an instruction of the PCM 1000. An air conditioner compressor 1016
is controlled in operation in accordance with an instruction of the
PCM 1000 in response to an operation state of the air conditioner
and an acceleration state of the engine. A power supply line 1015
is part of the power supply network of the present invention and
supplies power of the PCM itself from an FIM 1420 and supplies
power to the loads 1011 to 1014 described above. A multiplex
communication line 1017 is part of the power supply network
similarly and is provided to effect communication between control
units such as a BCM 1221.
[0423] FIG. 62 shows a detailed diagram of an internal construction
of the PCM 1000. The sensors 1001 to 1007 described above provide
analog input signals, and the analog input signals are inputted to
an analog input interface 1020, by which they are converted so that
they have a signal level (for example, 5 V of the full scale) with
which they can be processed readily by a CPU (Central Processing
Unit). Output signals of the switches 1009 and 1010 and the crank
angle sensor 1008 described above are digital signals and are
converted by a digital input interface 1021 so that they have a
signal level (for example, 5 V of the full scale) with which they
can be processed readily by a CPU 1024. The CPU 1024 converts the
aforementioned analog signals into digital signals by means of A/D
converters and fetches the digital signals into the inside of the
CPU. Similarly, the digital signals mentioned above are fetched
into the inside of the CPU from digital input ports via a digital
input interface. Three power supplies are used including power to
be supplied to the upstream side of each load, power to be supplied
to a constant voltage power supply 1026 for a communication IC 1025
in the PCM and power to be supplied to a constant voltage power
supply 1027, the digital input interface 1021 and an output
interface 1022 via a power supply cut-off switch 1028. The constant
voltage power supply 1026 is a constant voltage power generation
circuit for exclusive use for the communication IC and is normally
powered unless power supply from the FIM is cut-off.
[0424] The present circuit can be formed readily from a
three-terminal regulator. The constant voltage power supply 1027
supplies power to the CPU 1024 and the analog input interface 1020.
The power supply cut-off switch 1028 is controlled directly by the
communication IC and is provided in order to cut-off power supply
when a trouble occurs with a grounded type load (to which the air
conditioner compressor 1016 corresponds in the present embodiment).
The circuit has such a detailed construction as described
hereinabove with reference to FIG. 11. The communication IC 1025 is
connected to the multiplex communication line 1017 via a
communication IC interface 1023. Further, the communication IC 1025
is connected to the CPU 1024 and effects transmission and reception
of data to and from the power supply network via the multiplex
communication line 1017. Detailed description of functions of the
communication IC 1025 and the communication IC interface 1023 is
such as described hereinabove, and it is omitted here. The CPU 1024
includes a ROM (Read Only Memory) and a RAM (Random Access Memory)
provided in the inside thereof, and control software for the PCM
and initial constants are stored in the ROM.
[0425] In the present embodiment, as loads to the PCM, the injector
1012 (solenoid load), the ignition system 1011 (coil load), the AT
solenoid 1013 (solenoid load), the cooling fan motor 1014 (motor
load) and an air compressor clutch (solenoid load) are presumed,
and signals between the output interface 1022 and the CPU 1024
include driving signals and state detection signals of the
individual loads mentioned above. Details of the signals are
described below.
[0426] FIG. 63 shows a detailed construction of the output
interface 1022. This figure shows a driving circuit for a power
supply connected type load. In the present embodiment, this driving
circuit is applied to the injector 1012, ignition system 1011, AT
solenoid valve 1013 and cooling fan 1014. A load 1033 is connected
to the drain of an N-channel type FET (low side driver) 1032. A
driving signal 1030 controlled by the CPU 1024 is connected to the
gate of the FET 1032 so that the FET 1032 effects control of the
load in response to on off of the driving signal. A state detection
signal 1031 monitors the voltage of the drain to which the load
1033 is connected. The state detection signal exhibits, based on
the state of the load driving signal, such values as indicated in
the following table (in this table, VB is the battery voltage, VDS
is the voltage between the drain and the source of the FET, and RL
is the dc resistance of the load (where r>>RL)).
12 TABLE 11 Not driven (FET off) Driven (FET on) Normal R2 * VB/(RL
+ R1 + R2) R2 * VDS/(R1 + R2) Load opened R2 * VB/(r + R1 + R2) R2
* VDS/(R1 + R2) Load short-circuited R2 * VB/(R1 + R2) R2 * VD/(R1
+ R2) Load grounded 0 0
[0427] From this table, a failure state can be detected based on a
combination of state detection signals corresponding to a driven
state of the load.
[0428] FIG. 64 shows a detailed construction of the output
interface 1022 similarly. This figure shows a driving circuit for a
grounded type load, and in the present embodiment, the air
conditioner compressor clutch 1016 corresponds to this circuit. A
load 1035 is connected to the source of a P-channel type FET (high
side driver) 1034. The driving signal driving signal 1030
controlled by the CPU 1024 is connected to the gate of the FET 1034
so that the FET 1034 effects control of the load in response to
on/off of the driving signal. The state detection signal 1031
monitors the voltage of the source to which the load 1033 is
connected. The state detection signal exhibits, based on the state
of the load driving signal, such values as indicated in the
following table (in this table, VB is the battery voltage, and VDS
is the voltage between the drain and the source of the FET).
13 TABLE 12 Not driven (FET off) Driven (FET on) Normal (R1 + RL) *
VB/ VB - R2 * VDS/(R1 + R2) (RL + R1 + R2) Load opened (R1 + r) *
VB/ VB - R2 * VDS/(R1 + R2) (r + R1 + R2) Load short-circuited VB
VB Load grounded R1 * VB/(R1 + R2) R1 * VB/(R1 + R2)
[0429] Similarly, a failure state can be detected from this table
based on a combination of state detection signals corresponding to
a driven state of the load.
[0430] FIG. 65 shows an example of the digital input interface.
When a switch 1036 is off, a voltage is clipped by a Zener diode
1037 and an input signal 1038 exhibits a high level. When the
switch 1036 is on, the input signal 1038 exhibits a low level. A
capacitor C in FIG. 65 is provided in order to remove noise. Those
signals are fetched by the CPU 1024.
[0431] FIG. 66 shows a distributed situation of loads regarding the
PCM to an IPM 1060 described above. Since the IPM is provided to
control elements relating to the instrument panel, switches and
alarm lamps around the driver are distributed. A defogger switch
1043 and an OD (Over Drive) switch 1044 provide input signals
relating to the PCM. In order to raise the idling speed of the
engine when the rear defogger is turned on, a state of the defogger
switch is transferred from the IPM to the PCM via the BCM. The OD
switch 1044 is used to turn on or off of the over drive of the
automatic transmission, a state of it is transferred similarly to
the PCM. An exhaust gas temperature alarm lamp 1049, an engine
alarm lamp 1050 and an OD off lamp 1051 are incorporated in the
meter panel, and driving data thereof are transferred individually
from the PCM to the IPM via the BCM.
[0432] FIG. 67 shows a distributed situation of loads relating to
the PCM to an RIM 1070 described above. In the present embodiment,
a fuel pump 1048 built normally in a fuel tank and positioned
remotest from the PCM is controlled by the RIM 1070. A control
signal of the fuel pump 1048 is sent from the PCM to the RIM via
the BCM.
[0433] FIG. 68 shows a conventional example of a PCM system
construction and illustrates a wiring line reduction effect by the
present invention. Since an ignition switch signal is fetched by
the BCM and transmitted by multiplex communication, wiring lines
for a starter switch 1041 and an ignition switch 1047 can be
reduced. Since power is supplied from the FIM to the PCM and an
over-current state of the PCM is supervised by the FIM, fuses 1045
and 1046 on the upstream can be reduced. Simultaneously, the
necessity for wiring a power supply line from the battery to the
PCM via the fuse box in the compartment is eliminated, and the
wiring line can be reduced as much. The power supply line for
backing up the battery is eliminated by transferring data necessary
for backing up when power supply to the PCM is cut-off to the BCM
by multiplex communication as hereinafter described. Since signals
of the exhaust gas temperature alarm lamp 1049, engine alarm lamp
1050, OD off lamp 1051, defogger switch 1043 and OD switch 1044 are
transferred by multiplex communication via the IPM as described
hereinabove, the necessity for wiring individual lines to them is
eliminated, and the wiring lines can be reduced. Since a signal of
an air conditioner switch 1042 is transferred from an air
conditioner control unit which is hereinafter described to the PCM
by multiplex communication, the wiring line for it can be reduced
similarly. An engine rotation pulse signal 1052 is produced by the
PCM and transmitted to the other control units by multiplex
communication. The vehicle speed pulse signal is produced by the
ABS control unit and transmitted to the other control units by
multiplex communication. Since also a self diagnosis 1053 is
executed by multiplex communication, wiring lines for it can be
reduced similarly.
[0434] FIG. 69 illustrates a basic control flow of the PCM of the
present invention. After power supply is made available by the FIM,
processing is started from a reset state 1090. After such
resetting, the processing advances to initialization processing
1091, by which initialization of the entire system is performed.
Then, the processing advances to engine control processing 1092, in
which engine control such as fuel injection and ignition is
performed based on input information of the various sensors.
Thereafter, the processing advances to AT control processing 1093,
in which speed changing control is performed based on the input
signals from the sensors similarly. Then, the processing advances
to self diagnosis processing 1094, in which self diagnosis of the
sensors and actuators in the system is performed. Then, the
processing advances to transmit data writing processing 1095, in
which data to be transmitted from the PCM to another control unit
are written into the communication IC. In discrimination processing
1096, it is discriminated whether or not the ignition key switch is
in an off-state, and if the ignition key switch is in an off-state,
then the processing advances to ending processing 1097, but if the
ignition key switch is in an on-state, then the processing advances
to the engine control processing 1092. In the ending processing
1097, transfer processing of backup data is performed. After the
data transfer is completed, the processing advances to an end state
1098, in which the PCM makes preparations for power supply
interruption by the FIM.
[0435] FIG. 70 shows an analog signal input processing flow. The
present processing is started by a timer interrupt and successively
performs air flow sensor output value reading processing 1101,
coolant temperature sensor output value reading processing 1102, O2
sensor output value reading processing 1103, throttle sensor output
value reading processing 1104, knock sensor output value reading
processing 1105, exhaust gas temperature sensor output value
reading processing 1106 and AT oil temperature sensor output value
reading processing 1107, whereafter the processing returns from the
interrupt processing.
[0436] FIG. 71 illustrates an engine speed measurement processing
flow. Also the present processing is started by a timer interrupt.
By crank angle sensor pulse count processing 1111, the number of
crank angle sensor pulses after the preceding interrupt processing
till the current interrupt processing is measured. By engine speed
calculation processing, the number of rotation of the engine is
calculated from the timer interrupt period and the pulse number
mentioned above, and the processing returns from the interrupt by
processing 1113.
[0437] FIG. 72 illustrates details of the initialization processing
1091 in the basic control flow described above. By processor
initialization processing 1121, initialization processing of the
CPU is performed. By backup data transmit requesting processing
1122, a transfer request for the backup data backed up by the BCM
is transmitted. This is performed by setting and transmitting the
operation OK bit of the PCM transmission data as described
hereinabove. By discrimination processing 1123, contents of the
initial value data transferred are discriminated. When the backup
data are not normal such as when the BCM itself fails in backing up
and stored data are destroyed or when the backup data cannot be
transferred because of failure in operation of the BCM, the
processing advances to processing 1125, in which the ROM data in
the PCM are adopted as initial values. When the transfer data are
normal, the backup data are read in by processing 1124. After the
data setting is completed, the processing advances to an end state
1126, thereby ending the initialization.
[0438] FIG. 73 illustrates details of the engine control processing
1092 in the basic control flow described hereinabove. By processing
1131, the intake air amount is calculated based on data measured by
the air flow sensor. By processing 1133, the fuel injection amount
is calculated and the injection pulse width of the injector is
calculated using the speed calculated by the engine speed
calculation processing described above and the intake air amount.
By processing 1134, the injector is driven based on the calculated
pulse width. By processing 1135, the driving signal of the injector
and the output state signal are monitored, and the states of the
load and the driving element in the output interface are supervised
based on Table 11 given hereinabove. By power supply cut-off
processing (L) 1136, failure diagnosis of the high side load (in
this instance, the injector) by the low side driving element and
incidental cut-off processing are performed based on a result of
the supervision mentioned above. By processing 1137, an ignition
timing is calculated using the speed of rotation calculated by the
engine speed calculation processing described above and data such
as a knock sensor signal. By processing 1138, the ignition coil is
energized (driven) based on the calculated ignition timing. By
processing 1139, the driving signal of the ignition coil and the
output state signal are monitored, and the load and the state of
the driving element in the output interface are supervised based on
Table 11 given hereinabove. By power supply cut-off processing (L)
11310, failure diagnosis of the high side load (in this instance,
the ignition coil) by the low side driving element and incidental
interruption processing are performed based on a result of the
supervision mentioned above. By processing 11311, a cooling fan
motor driving mode is calculated using the speed of rotation
calculated by the engine speed calculation processing described
above and data such as a coolant temperature signal. By processing
11312, the motor is driven based on the calculated driving mode. By
processing 11313, the driving signal of the cooling fan motor and
the output state signal are monitored, and the load and the state
of the driving element in the output interface are supervised based
on Table 11 given hereinabove. By power supply cut-off processing
(L) 11314, failure diagnosis of the high side load (in this
instance, the cooling fan motor) by the low side driving element
and incidental interruption processing are performed based on a
result of the supervision described above. By processing 11315, a
fuel pump driving mode is calculated using data such as the speed
of rotation calculated by the engine speed calculation processing
described above. By processing 11316, the pump (motor) is driven
based on the calculated driving mode. By processing 11317, the
driving signal of the fuel pump motor and the output state signal
are monitored, and the load and the state of the driving element in
the output interface are supervised based on Table 11 given
hereinabove. By power supply cut-off processing (L) 11318, failure
diagnosis of the high side load (in this instance, the fuel pump
motor) by the low side driving element and incidental interruption
processing are performed based on a result of the supervision
mentioned above. By processing 11319, an air conditioner compressor
clutch driving mode is calculated using the speed of rotation
calculated by the engine speed calculation processing described
above and the coolant temperature sensor signal as well as data
such as a state of the air conditioner switch transferred from the
air conditioner control unit. By processing 11320, the compressor
clutch is driven based on the calculated driving mode. By
processing 11321, the driving signal of the compressor clutch and
the output state signal are monitored, and the load and the states
of the driving elements in the output interface are supervised
based on Table 12 given hereinabove. By power supply cut-off
processing (H) 11322, failure diagnosis of the low side load (in
this instance, the compressor clutch) by the high side driving
element and incidental cut-off processing are performed based on a
result of the supervision mentioned above. By discrimination
processing 11323, an abnormal state of the engine is detected, and
if it is discriminated that the engine is in an abnormal state,
then the processing advances to fail safe processing 11324, but if
it is discriminated that the engine is in a normal state, then the
processing advances to abnormal exhaust gas temperature
discrimination processing 11326. In the fail safe processing 11324,
fail safe processing determined in advance is executed in response
to a failure mode, and then the processing advances to engine alarm
lamp lighting instruction processing 11325. By the engine alarm
lamp lighting instruction processing 11325, the abnormal occurrence
bit of the transfer data from the PCM to the BCM is set to provide
an alarm lamp lighting instruction. By the abnormal exhaust gas
temperature discrimination processing 11326, it is discriminated
based on the exhaust gas temperature sensor signal whether or not
the exhaust gas temperature is excessively high. If the exhaust gas
temperature is higher than a preset value, then it is discriminated
that the exhaust gas temperature is abnormal, and the processing
advances to fail safe processing 11327. If the exhaust gas
temperature is normal, then the processing advances to an end state
11329 in order to end the engine controlling processing. By the
fail safe processing 11327, the fail safe processing determined in
advance is executed in response to the failure mode, and then the
processing advances to exhaust gas temperature alarm lamp lighting
instruction processing 11328. By the exhaust gas temperature alarm
lamp lighting instruction processing 11328, the abnormal exhaust
gas temperature occurrence bit of the data to be transferred from
the PCM to the BCM is set to provide an alarm lamp lighting
instruction.
[0439] FIG. 74 illustrates details of the AT control processing
1093 in the basic control flow described above. By processing 1140,
the accelerator opening is read in from a throttle sensor signal.
By processing 1142, the gear position of the transmission is read
in from the shift inhibitor switch signal. By processing 1143, the
vehicle speed signal transferred from the ABS control unit is read
in. By discrimination processing 1144, it is discriminated whether
or not the over drive switch has been cancelled. If the over drive
switch has been cancelled, then the processing advances to
processing 1145, but if the OD is set, then the processing advances
to processing 1146. By the OD cancellation lamp lighting
instruction processing 1145, the OD cancellation bit of the data to
be transferred from the PCM to the BCM is set to provide a
cancellation lamp lighting instruction. By processing 1146, the
gear position of the AT is set from the engine speed, the throttle
opening and so forth, and a driving mode of the corresponding
solenoid is calculated. By processing 1147, the driving signal of
the AT solenoid and the output state signal are monitored, and the
load and the state of the driving element in the output interface
are supervised based on Table 1 given hereinabove. By power supply
interruption processing (L) 1149, failure diagnosis of the low side
load (in this instance, the AT solenoid) by the high side driving
element and incidental interruption processing are performed based
on a result of the supervision described above, and the processing
advances to an end state 11410.
[0440] FIG. 75 illustrates details of the power supply cut-off
processing (L) 1136. When it is discriminated that the load state
is a battery short-circuited state (short-circuiting of the load to
power supply) discrimination processing 1151 or load
short-circuiting discrimination processing 1152, since this is a
state wherein a voltage continues to be normally applied to the
driving element in the output stage, normal interruption (off) of
the load is selected by processing 1157. If it is discriminated by
load open discrimination processing 1153 or driving element open
failure (same as the normal load interruption state) discrimination
processing 1154 that the load state is a load open or driving
element open state, since this is a state in which driving of the
load is impossible, an alarm is generated by processing 1158. If it
is discriminated by load grounding (ground short-circuiting)
discrimination processing 1155 or driving element short-circuit
failure discrimination processing 1156 that the load state is a
load grounded or driving element short-circuited failure, since the
load is in a normally powered state and load control by the PCM
side is impossible, an cut-off instruction is generated by
processing 1.159 to request for cut-off of the PCM power supply for
the FIM on the upstream of the PCM.
[0441] FIG. 76 illustrates details of the power supply cut-off
processing (H) 11322 described hereinabove. When it is
discriminated by load grounding discrimination processing 1161 or
load short-circuiting discrimination processing 1162 that the load
state is a battery short-circuited or short-circuited state, since
this is a state wherein a voltage continues to be normally applied
to the driving element in the output stage, normal cut-off (off) of
the load is selected by processing 1167. If it is discriminated by
load open discrimination processing 1163 or driving element open
failure (same as the normal load interruption state) discrimination
processing 1164 that the load state is a load open or driving
element open state, since this is a state wherein the load cannot
be driven, an alarm is generated by processing 1168. If it is
discriminated by battery short-circuiting discrimination processing
1165 or driving element short-circuit failure discrimination
processing 1166 that the load state is a battery short-circuited or
load element short-circuited failure state, since the load is in a
normally energized state and load control by the PCM is impossible,
an cut-off instruction is generated by processing 1169 to request
for cut-off of power supply to the PCM by the FIM on the upstream
of the PCM.
[0442] FIG. 77 illustrates details of the transmit data writing
processing 1095 in the basic control flow described above. By
processing 1171, in order to transmit data individually to the
different control units, a transmission mode of the communication
IC is designated to the physical address. Discrimination of a
destination of transmission is performed by discrimination
processing 1172, 11710 and 11714. When the destination of
transmission is the BCM, the processing advances to processing
1173. When the destination of transmission is the air conditioner
control unit, the processing advances to processing 11711. When the
destination of transmission is the ABS control unit, the processing
advances to processing 11715. By the processing 1173, the
transmission destination address is set to the BCM. By the
processing 1174, the OD cancellation lamp signal is set; by the
processing 1175, the engine alarm lamp is set; by processing 1176,
the exhaust gas temperature alarm lamp is set; by processing 1177,
the shift position lamp in the meter panel is set; by processing
1178, the fuel pump is set; and by processing 1179, data or a bit
of a power supply cut-off of the PCM itself is set, and is written
into the communication IC. By the processing 11711, the
transmission destination address is set to the air conditioner. By
processing 11712, an air conditioner cut signal is set, and by
processing 11713, coolant temperature data is set, and written into
the communication IC. By the processing 11715, the transmission
destination address is set to the ABS. By the processing 11716, the
engine speed data is set and written into the communication IC.
After the data is written, the communication IC performs data
transmission processing to the designated transmission
destination.
[0443] FIG. 78 illustrates details of the ending processing 1097 in
the basic control flow described above. By processing 1181, the
transmission mode is set to the physical address transmission mode.
By processing 1182, the transmission destination address is set to
the BCM. The backup data is transmitted to the BCM by processing
1183 until it is discriminated by processing 1184 that all of the
backup data have been transmitted. After completion of transmission
of all of the backup data, the processing advances to processing
1185, by which the power supply interruption permission signal bit
of the PCM itself is set and transmitted, thereby ending the ending
processing.
[0444] FIG. 79 illustrates a multiplex communication data reception
processing flow. Since the construction wherein external interrupt
occurs with the CPU upon reception of data of the communication IC
is employed, the present processing is started by external
interrupt by processing 1190. By processing 1191, it is
discriminated whether or not the receive data has been obtained by
broadcast communication or individual communication. When the
receive data has been obtained by broadcast communication, it is
discriminated by discrimination processing 1192, 11910 and 11912
whether the transmission destination is the BCM, the ABS or the
SDM. If the transmission destination is the BCM, then ignition key
switch position information is read in by processing 1193; light
switch position information is read in by processing 1194; brake
lamp switch information is read in by processing 1195; parking
brake switch information is read in by processing 1196; OD switch
information is read in by processing 1197; and rear defogger switch
information is read in by processing 1198, from the communication
IC. When the transmission destination is the ABS, the vehicle speed
is read in by processing 11911. When the transmission destination
is the SDM, a collision detection signal is read in by processing
11931. When the receive data has been obtained by individual
communication, it is discriminated by processing 1199 and 11915
whether the transmission destination is the air conditioner or the
self diagnosis apparatus. If the transmission destination is the
air conditioner, then a compressor off signal is read in by
processing 11914. If the transmission destination is the self
diagnosis apparatus, then a diagnosprocesses command is read in by
processing 11916, and corresponding self diagnosis processing is
performed by the self diagnosprocesses in the main routine.
[0445] FIG. 80 is a system diagram showing a construction of an air
bag module (hereinafter referred to as SDM) to which the power
supply network of the present invention is applied. A control
module 1200 receives various sensor signals necessary for air bag
control upon collision and outputs driving signals for various
actuators in accordance with a control method determined in
advance. A safing sensor 1201 is a double system sensor upon
operation of an air bag. A G sensor 1202 detects the G upon
collision, converts it into an electric signal and outputs the
electric signal. A connector lock detection sensor 1203 detects a
coupled state of a connector. A driver's seat inflator 1204 and an
passenger's seat inflator 1205 are bags which are inflated by
explosion caused in the insides thereof by a CPU when collision is
detected. A power supply line 1207 is part of the power supply
network of the present invention and supplies power to the SDM
itself and supplies power to the loads 1204 and 1205 mentioned
above from a BCM 1221. A multiplex communication line 1206 is part
of the power supply network similarly and is provided to effect
communication with a control unit such as the BCM 1221.
[0446] FIG. 81 is a detailed diagram of the internal construction
of the SDM module 1200. The G sensor 1202 provides an analog input
signal, and the analog input signal is inputted to an analog input
interface 1210, by which it is converted so that it has a signal
level (for example, 5 V of the full scale) with which the CPU
(Central Processing Unit) can process the signal readily. The CPU
1214 converts the analog signal mentioned above into a digital
signal by means of an A/D converter and fetches it into the inside
of the CPU. Powers supplied from the BCM include power to be
supplied to a constant voltage power supply 1215 for a
communication IC 1216 in the SDM and power to be supplied to the
constant voltage power supply 1215 and an output interface 1213 via
a power supply cut-off switch 1218. Another constant voltage power
supply 1217 is a constant voltage power supply generation circuit
for exclusive use for the communication IC and is normally powered
unless power supply from the BCM is cut off. The present circuit
can be formed from a three-terminal regulator and so forth. The
constant voltage power supply 1215 supplies power to the CPU 1214
and the analog input interface 1210. The power supply cut-off
switch 1218 is controlled directly by the communication IC and is
provided to cut-off power supply when a trouble occurs with a
grounded type load. The communication IC 1216 is connected to the
multiplex communication line 1206 via the communication IC
1212.
[0447] Further, the communication IC 1216 is connected to the CPU
1214 so that it transmits and receives data necessary for the power
supply network via the multiplex communication line 1206. Detailed
description of functions of the communication IC 1216 and the
communication IC 1212 is omitted here. The CPU 1214 includes a ROM
(Read Only Memory) and a RAM (Random Access Memory) provided
therein, and control software for the SDM and initial constants are
stored in the ROM. Since the air bag driving circuit of the output
interface 1213 is basically same as the door motor driving circuit
of the air conditioner control unit, detailed description of the
same is omitted.
[0448] FIG. 82 illustrates a distribution situation of loads to the
BCM 1221 and the IPM 1060 described hereinabove relating to the
SDM. In the present embodiment, the BCM supplies power to the SDM.
The ignition switch 1047 provides an input signal relating to the
SDM. An air bag alarm lamp 1220 is incorporated in the meter panel,
and driving data is transferred from the SDM to the IPM via the
BCM.
[0449] FIG. 83 shows a conventional example of an SDM system
construction and illustrates wiring line reduction effects by the
present invention. Since an ignition switch signal is fetched by
the BCM and transmitted by multiplex communication, wiring lines
relating to the ignition switch 1047 can be reduced. Since the SDM
receives supply of power from the BCM and an over-current state of
the SDM is supervised by the BCM, fuses 1221 and 1222 on the
upstream can be reduced. Simultaneously, the necessity for laying
power supply lines from the battery to the SDM via the fuse box in
the compartment is eliminated, and wiring lines can be reduced as
much. Power supply lines for backing up the battery become
unnecessary by transferring, when power supply to the SDM is
cut-off, data necessary for the backing up by multiplex
communication to the BCM as hereinafter described. Since a signal
is transferred by multiplex communication via the IPM as described
hereinabove, the necessity for individually laying wiring lines to
the air bag alarm lamp 1220 is eliminated, and wiring lines are
reduced. Also self diagnosis 1230 is executed by multiplex
communication, wiring lines for the same can be reduced
similarly.
[0450] FIG. 84 illustrates a basic control flow of the SDM of the
present invention. After power to the BCM is made available,
processing starts from a reset state 1240. After the resetting, the
processing advances to initialization processing 1241, by which
initialization of the entire system is performed. Then, the
processing advances to air bag control processing 1242, by which
inflator control is performed based on input information of various
sensors. Thereafter, the processing advances to self
diagnosprocesses 1243, by which self diagnosis of the sensors and
actuators in the system is performed. Then, the processing advances
to transmission data writing processing 1244, by which data to be
transmitted from the SDM to another control unit are written into
the communication IC. By discrimination processing 1255, it is
discriminated whether or not the ignition key switch is in an off
state, and if the key switch is in an off state, then the
processing advances to ending processing 1256, but if the key
switch is in an on state, then the processing advances to brake
control processing 1252. By the ending processing 1256, transfer
processing of the backup data is performed. After the data transfer
is completed, the processing advances to an end state 1257 to make
preparations for power supply cut-off by the BCM. Since
initialization processing 1251 and ending processing 1256 in the
basic control flow chart described above are same as those in the
PCM control described above, detailed description of the same is
omitted.
[0451] FIG. 85 illustrates details of the air bag control
processing 1242 in the basic control flow described above. In
discrimination processing 1251, it is discriminated whether or not
the SDM has some trouble. If the SDM has some trouble, then the
processing advances to processing 1257, by which fail safe
processing is performed. In the fail safe processing 1257, fail
safe processing determined in advance is performed in response to a
failure mode, and the processing advances to air bag alarm lamp
lighting instruction processing 1258. By the air bag alarm lamp
lighting instruction processing 1258, the trouble occurrence bit of
the data to be transferred from the SDM to the BCM is set to
provide an alarm lamp lighting instruction. When the SDM has no
trouble, the processing advances to processing 1252. By the
processing 1252, a collision state of the vehicle is calculated
from an output of the G sensor. By discrimination processing 1253,
it is discriminated whether or not the vehicle has collided. If it
is discriminated that the vehicle has collided, then the processing
advances to processing 1254, by which a squib is activated to
inflate the bag. By processing 1255, the driving signal and the
output state signal are monitored, and states of the load and the
driving element in the output interface are supervised based on
Table 3 which will be hereinafter described (in the section of the
air conditioner control unit). By power supply cut-off processing
1256, failure diagnosis of the load and incidental cut-off
processing are performed based on a result of the supervision
described above.
[0452] FIG. 86 illustrates details of the transmission data writing
processing 1244 in the basic control flow described hereinabove. By
discrimination processing 1261, a transmission data mode is
selected. In the case of broadcast communication, the processing
advances to processing 1265, by which a functional address is set
to the transmit data. In the case of individual communication, the
processing advances to processing 1262, by which a physical address
is set. By the processing 1265, in order to transmit collision
detection data to the individual control units simultaneously, a
transmission mode of the communication IC is designated to the
functional address. By processing 1266, the collision information
is set to the communication IC. By processing 1263, a transmission
destination address is set to the BCM. By processing 1264, setting
of the air bag alarm lamp is written into the communication IC. By
processing 1267, the power supply cut-off designation bit of the
SDM itself is set and written into the communication IC. After the
data is written in, the communication IC effects data transmission
processing to the designated transmission destination.
[0453] FIG. 87 illustrates a multiplex communication data receive
processing flow. Upon reception of data of the communication IC,
external interrupt occurs with the CPU, and the present processing
is started by the interrupt. By discrimination processing 1181, it
is discriminated whether or not the receive data is broadcast
communication data. If the receive data is obtained by broadcast
communication, then the processing advances to processing 1183, by
which ignition key switch position information is read in. Then, by
processing 1184, a stop lamp switch state is read in. If the
receive data is not obtained by broadcast communication, then the
processing advances to discrimination processing 1182. When the
transmission destination is the self diagnosis apparatus, a
diagnoses processing command is read in by processing 1185, and
corresponding self diagnosprocesses is performed in the self
diagnosprocesses in the main routine.
[0454] FIG. 88 is a system diagram showing a construction of the
air conditioner control unit for a vehicle to which the power
supply network of the present invention is applied. A control unit
1300 receives various sensor signals necessary for control of the
air conditioner and outputs driving signals for various actuators
in accordance with a control method determined in advance. An
external air temperature sensor 1301 measures the temperature
outside the compartment, converts it into an electric signal and
outputs the electric signal. An internal air temperature sensor
1302 measures the temperature in the inside of the compartment,
converts it into an electric signal and outputs the electric
signal. An sunshine sensor 1303 measures a sunshine amount,
converts it into an electric signal and outputs the electric
signal. An air mix door opening sensor 1304 detects an opening of
an air mix door, which mixes warm air and cool air with each other,
in the form of an analog value and outputs the analog value. A
preset temperature input 13011 outputs a desired preset room
temperature in the form of an analog value. A mode door position
switch 1305 detects the position of a door which effects mode
setting of an air ortlet. An intake door position switch 1306
detects the position of an intake selection door for blown off air.
An automatic switch 1307 is a switch for setting the operation mode
of the air condition to automatic or manual. An air conditioner
switch 1308 is a switch for selecting on or off of operation of the
compressor. A mode switch 1309 is a switch for selecting an air
ortlet. A fan switch 13010 is a switch for selecting an amount of
wind of the fan when the air conditioner is in a manual mode. An
intake door actuator 13012 is a motor for driving an air intake
selection flap and is rotatable in both of the forward and reverse
directions. An air mix door actuator 13013 is a motor for driving
the air mix door and is rotatable in both of the forward and
reverse directions. A mode door actuator 13014 is a motor for
driving a mode door and is rotatable in both of the forward and
reverse directions. A blower fan motor 13015 is a motor for
controlling the amount of wind to be blown out. A power supply line
13016 is part of the power supply network of the present invention
and supplies power from the FIM 1420 to the air conditioner control
unit itself and supplies power to the loads 13012 to 13015
mentioned above. A multiplex communication line 13017 is part of
the power supply network similarly and is provided to effect
communication with another control unit such as the BCM 1221.
[0455] FIG. 89 shows a detailed diagram of an internal construction
of the air conditioner control unit 1300. The sensors 1301, 1302,
1303, 1304 and 13011 mentioned above provide analog input signals,
and the analog input signals are inputted to an analog input
interface 1310, by which they are converted so that they have a
signal level (for example, 5 V of the full scale) with which they
can be processed readily by a CPU (Central Processing Unit) 1314.
The output signals of the switches 1305 to 13010 mentioned above
are digital signals, and the digital signals are converted by a
digital input interface 1311 so that they have a signal level (for
example, 5 V of the full level) with which they can be processed
readily by the CPU 1314. The CPU 1314 converts the analog signals
mentioned above into digital signals by means of A/C converters and
fetches the digital signals into the inside of the CPU. Similarly,
the CPU 1314 fetches the digital signals mentioned above into the
inside of the CPU from the digital input port via the digital input
interface. Three powers are supplied from the FIM including power
to be supplied to the upstream side of each load, power to be
supplied to a constant voltage power supply 1317 for a
communication IC 1315 in the air conditioner control unit, and
power to be supplied to another constant voltage power supply 1316,
the digital input interface 1311 and an output interface 1313 via a
power supply cut-off switch 1318. The constant voltage power supply
1317 is a constant voltage power supply generation circuit for
exclusive use for the communication IC and is normally energized
unless power supply from the FIM is cut-off. The present circuit
can be formed readily from a three-terminal regulator and so forth.
The constant voltage power supply 1316 supplies power to the CPU
1314 and the analog input interface 1310. The power supply cut-off
switch 1318 is controlled directly by the communication IC and is
provided in order to cut-off power supply when a trouble occurs
with the motor loads (intake door actuator 13012, air mix door
actuator 13013 and mode door actuator 13014). The communication IC
1315 is connected to the multiplex communication line 13017 via a
communication IC interface 1312. Further, the communication IC 1315
is connected to the CPU 1314 and effects transmission and reception
of data necessary for the power supply network via the multiplex
communication line 13017. Since functions of the communication IC
1315 and the construction of the communication IC interface 1312
are similar to those described hereinabove, detailed description of
them is omitted here. The CPU 1314 includes a ROM (Read Only
memory) and a RAM (Random Access Memory) provided therein, and
control software for the air conditioner control unit and initial
constants are stored in the ROM.
[0456] FIG. 90 shows a detailed construction of the output
interface 1313. The load 13012 is connected in an H bridge formed
from two sets of N-channel FETs (low side drivers) 1322 and 1323
and P-channel FETs (high side drivers) 1320 and 1321. Driving
signals 1324, 1325 and 1326 controlled by the CPU 1314 are
converted in level by resisters R and r and transistors 13210,
13211, 13212, 13213, 13214 and 13215 and drive the gates of the
individual FETs. State detection signals 1328 and 1329 monitor
voltages at the opposite terminals of the load 13012. The state
detection signal exhibits, based on the state of the load driving
signal, such values as indicated in the following table (in the
table, VB is the battery voltage, VDSH is the voltage between the
drain and the source of the P-channel FETs, VDSL is the voltage
between the drain and the source of the N-channel FETs, RL is the
dc resistance of the load, and Z is the level fixing resistance
value for the state detection signal).
14 TABLE 13 Not driven (stopped) Driven(rotated) Upstream/
Upstream/down- downstream side stream side of of load load Normal
0/0 VB - VDSH/VDSL Load opened 0/0 VB - VDSH/0 Load short- 0/0
Egual in voltage circuited between upstream and downstream Battery
short- VB//VB * Z/(RL + Z) VB/VDSL circuit on upstream of load
Battery short- VB * Z/(RL + Z)/VB VB - VDSH/VB circuit on
downstream of load Load grounded on 0/0 0/0 upstream of load Load
grounded on 0/0 VB - VDSH/0 downstream of load
[0457] From the present table, a failure state can be detected
based on a combination of state detection signals corresponding to
load driving states.
[0458] Since the digital input interface is same as that described
hereinabove with reference to FIG. 65, description is given with
reference to FIG. 65. When a switch 1336 is off, a voltage is
clipped by a Zener diode 1337, and an input signal 1338 exhibits a
high level. When the switch 1336 is on, the input signal 1338
exhibits a low level. A capacitor C in FIG. 65 is provided in order
to remove noise. Those input signals are fetched by the CPU
1314.
[0459] FIG. 91 illustrates a distribution situation of loads to an
IPM 1330 described above relating to the air conditioner control
unit. Since the IPM is provided to control elements relating to the
instrument panel, switches and alarm lamps around a driver are
disposed for the IPM. A headerlamp switch 1331 and an ignition
switch 1333 provide input signals relating to the air conditioner
control unit. In order to light the illumination for the air
conditioner panel when the headerlamps are turned on, the state of
the headerlamp switch is transferred from the IPM to the air
conditioner control unit via the BCM.
[0460] FIG. 92 shows a conventional example of a system
construction of an air conditioner control unit and illustrates
wiring line reduction effects by the present invention. Since an
ignition switch signal is fetched by the BCM and transmitted by
multiplex communication, wiring lines relating to the ignition
switch 1333 can be reduced. Since the air conditioner control unit
receives supply of power from the BCM and an over-current state of
the air conditioner control unit is supervised by the BCM, fuses
1340 to 1342 on the upstream can be reduced.
[0461] Simultaneously, the necessity for laying power supply lines
from the battery to the air conditioner control unit via the fuse
box in the compartment is eliminated, and wiring lines can be
reduced as much. A power supply line 1343 for backing up the
battery can be eliminated by transferring, when power supply to the
air conditioner control unit is cut-off, data necessary for the
backing up to the BCM by multiplex communication as hereinafter
described. Since a coolant temperature sensor 1002 and a compressor
clutch 1344 serve as input and output apparatus of the PCM, the air
control unit is controllable by multiplex communication via the
PCM, and reduction of wiring lines can be achieved. Since a signal
is transferred by multiplex communication via the IPM as described
hereinabove, the necessity for laying wiring lines individually to
the headerlamp switch 1331 is eliminated and wiring lines can be
reduced. Also self diagnosis 1353 is executed by multiplex
communication, wiring lines for the same can be reduced
similarly.
[0462] FIG. 93 illustrates a basic control flow of the air
conditioner control unit of the present invention. After power
supply is made available by the BCM, processing is started from a
reset state 1350. After the resetting, the processing advances to
initialization processing 1351, by which initialization of the
entire system is performed. Then, the processing advances to air
conditioner control processing 1352, by which control of the doors
and the motors is performed based on input information of various
sensors. Thereafter, the processing advances to self
diagnosprocesses 1353, by which self diagnosis of the sensors and
actuators in the system is performed. Then, the processing advances
to transmit data writing processing 1354, by which data to be
transmitted from the air conditioner control unit to another
control unit is written into the communication IC. In the present
embodiment, since the air conditioner control unit serves as a
backing up control unit when the BCM fails, it is discriminated by
discrimination processing 1355 whether or not an ACK (acknowledge
signal) of the BCM has been sent back thereto. When no ACK signal
of the BCM has been received, since it is discriminated that the
BCM fails, the processing advances to processing 1356, by which BCM
backing up processing is performed. In the BCM backing up
processing of the processing 1356, states of input apparatus
connected to the BCM are fixed to predetermined values, and control
of such control units as the FIM and the RIM which are controlled
by the BCM is performed by the air conditioner control unit in
substitution. It is to be noted that, in the present embodiment,
since processing in substitution when the BCM fails is performed
only by the air conditioner control unit, the apparatus which
performs such processing is not limited to this, and naturally it
is otherwise possible that some other control unit or units having
a CPU perform such processing in substitution exclusively or
cooperatively. By discrimination processing 1357, it is
discriminated whether or not the ignition key switch is in an off
state, and if the ignition key switch is in an off state, then the
processing advances to ending processing 1358, but if the ignition
key switch is in an on state, the processing advances to the air
conditioner control processing 1352. By the ending processing 1358,
transfer processing of the backup data is performed. After the data
transfer is completed, the processing advances to an end state 1359
to make preparations for cut-off of power supply by the BCM.
[0463] FIG. 94 illustrates an analog signal input processing flow.
The present processing is started by timer interrupt, and sunshine
sensor output value reading processing 1161, internal air
temperature sensor output value reading processing 1162, external
air temperature output value reading processing 1163 and air mix
door opening sensor output value reading processing 1164 are
performed in order, whereafter the processing returns from the
interrupt processing.
[0464] FIG. 95 illustrates details of the air conditioner control
processing 1352 in the basic control flow described above. By
discrimination processing 1370, it is discriminated whether or not
the air conditioner is in an automatic mode. If the air conditioner
is in the automatic mode, then the processing advances to
processing 1379, but if the air conditioner is in a manual mode,
then the processing advances to the processing 1371. By the
processing 1379, a desired preset temperature is read in. By
processing 13710, a current internal air temperature is read in. By
discrimination processing 13711, it is discriminated whether or not
there is some temperature difference between the preset temperature
and the current internal temperature. When some temperature
difference is detected, the processing advances to processing 1371,
by which temperature adjustment is performed. When no temperature
difference is detected, the processing advances to processing 1375.
By the processing 1371, an opening of the air mix door is set in
accordance with a logic determined in advance. Similarly, by
processing 1372, the position of the intake door is set; by
processing 1373, the position of the mode door is set; and by
processing 1374, the an amount of the blower motor is set. By the
discrimination processing 1375, it is discriminated whether or not
the air conditioner switch is in an off state, and if the air
conditioner switch is in an off state, then the processing advances
to processing 1376, by which a compressor off signal is set. By
processing 1377, it is discriminated whether or not the air
conditioner system has some error, and when the air conditioner
system has some error, fail safe processing is performed by
processing 1378.
[0465] FIG. 96 illustrates details of the door opening setting
processing mentioned hereinabove. By processing 1381, a door
opening is calculated based on a predetermined logic. By processing
1382, the door motor is driven based on the calculated opening. By
processing 1383, the driving signal of the door motor and the
output state signal are monitored, and states of the load and the
driving element in the output interface are supervised based on
Table 3 given hereinabove. By power supply cut-off processing 1384,
failure diagnosis of the element and incidental cut-off processing
are performed based on a result of the supervision described
above.
[0466] FIG. 97 illustrates details of the blower fan wind amount
setting processing described above. By processing 1391, a blower
wind amount is calculated based a logic determined in advance. By
processing 1392, the blower motor is driven based on the calculated
wind amount. By processing 1393, the driving signal of the blower
motor and the output state signal are monitored, and states of the
load and the driving element in the output interface are supervised
based on Table 1 (same as that for the PCM control) given
hereinabove. By power supply cut-off processing 1394, failure
diagnosis of the element and incidental interruption processing are
performed based on a result of the supervision described above. The
present processing is basically same as the load driving processing
of the PCM.
[0467] FIG. 98 illustrates details of the power supply cut-off
processing 1384 described hereinabove.
[0468] If it is discriminated by load open discrimination
processing 13102 or one driving element open failure (same as
normal load cut-off state) discrimination processing 13103 that the
load is open or one driving element is in an open state, since this
is a condition wherein the load cannot be driven, an alarm is
generated by processing 131011. If it is discriminated by
discrimination processing 13104 that the load state is a battery
short-circuit state, by discrimination processing 13105 that the
load state is a grounded state, by discrimination processing 13106
that the load state is a short-circuited state, by discrimination
processing 13107 that two or more driving elements are in an open
failure or by discrimination processing 13108 that one driving
element is in a short-circuited failure, since this is a state
wherein a voltage continues to be normally applied to the driving
element in the output stage, normal cut-off (off) of the load is
selected by processing 131012. When it is discriminated by two or
more driving element short-circuit failure discrimination
processing 13109 that two or more driving elements are in a
short-circuit failure, since the load is in a normally energized
state and load control from the air conditioner control unit side
is impossible, an cut-off instruction is generated by processing
131010 to request for cut-off of power supply to the air
conditioner control unit at the BCM on the upstream of the air
conditioner control unit.
[0469] FIG. 99 illustrates details of the transmit data writing
processing 1354 in the basic flow chart described above. By
processing 13111, in order to transmit data individually to the
individual control units, a transmission mode of the transmission
IC is designated to a physical address. When it is discriminated by
discrimination processing 13112 that the transmission destination
is the PCM, the processing advances to processing 13113. By the
processing 13113, the transmission destination address is set to
the PCM and a compressor off signal is set, and they are written
into the communication IC. When it is discriminated by
discrimination processing 13114 that the transmission destination
is the BCM, the processing advances to processing 13115. By the
processing 13115, an operation confirmation signal for confirmation
of backing up of the BCM described hereinabove is transmitted to
the BCM. By processing 13116, in order to cut-off power supply upon
ending, a power supply cut-off signal is transmitted to the
BCM.
[0470] FIG. 100 illustrates a multiplex communication data receive
processing flow. Since the construction wherein external interrupt
occurs with the CPU upon reception of data of the communication IC
is adopted, the present processing is started by external interrupt
in a state 1190. By discrimination processing 13121, it is
discriminated whether or not the transmission destination is the
BCM. If the transmission destination is the BCM, ignition key
switch position information is read in by processing 13122, and
headerlamp switch position information is read in by processing
13123, from the communication IC. By discrimination processing
13124, it is discriminated whether or not the transmission
destination is the PCM. When the transmission destination is the
PCM, an air conditioner cut signal is read in by processing 13125
and a coolant temperature data signal is read in by processing
13126. By discrimination processing 13127, it is discriminated
whether or not the transmission destination is the PCM. When the
transmission destination is the self diagnosis apparatus, a
diagnosprocesses command is read in by processing 13128, and
corresponding self diagnosis processing is performed in the self
diagnosprocesses in the main routine.
[0471] FIG. 101 is a system diagram showing a construction of an
Antilock Brake System (hereinafter referred to as ABS) for a
vehicle to which the power supply network of the present invention
is applied. A control module 1400 receives various sensor signals
necessary for brake lock control upon braking and outputs driving
signals for various actuators in accordance with a control method
determined in advance. A right front wheel speed sensor 1401, a
left front wheel speed sensor 1402, a right rear wheel speed sensor
1403 and a left rear wheel speed sensor 1404 detect speeds of
rotation of the individual wheels and output them as pulse signals
to the ABS module 1400. An ABS motor 1405 intensifies the pressure
of brake fluid accumulated upon ABS control. ABS solenoids 1406,
1407 and 1408 control brake hydraulic pressure control valves for
the right front wheel, left front wheel and rear wheels,
respectively. A power supply line 1409 is part of the power supply
network of the present invention and supplies power to the ABS
itself and power to the loads 1405 to 1408 described above from the
FIM 1420. A multiplex communication line 14010 is part of the power
supply network similarly and is provided in order to allow
communication with a control unit such as the BCM 1221.
[0472] FIG. 102 is a detailed diagrammatic view showing an internal
construction of the ABS module 1400. The sensors 1401 to 1404
described above provide analog input signals, and the analog input
signals are inputted to an analog input interface 1410, by which
they are converted so that they have a signal level (for example, 5
V of the full scale) with which they can be processed readily by a
CPU (Central Processing Unit). The CPU 1413 converts the analog
signals mentioned above into digital signals by means of A/D
converters and fetches the digital signals into the inside of the
CPU. Three different powers are supplied from the FIM including
power to be supplied to the upstream side of each load, power to be
supplied to a constant voltage power supply 1416 for a
communication IC 1414 in the ABS and power to be supplied to
another constant voltage power supply 1415 and an output interface
1411 via a power supply cut-off switch 1417. The constant voltage
power supply 1416 is a constant voltage power supply generation
circuit for exclusive use for the communication IC and is normally
energized unless power supply from the FIM is cut off. The present
circuit can be formed simply from a three-terminal regulator and so
forth. The constant voltage power supply 1415 supplies power to the
CPU 1413 and the analog input interface 1410. The power supply
cut-off switch 1417 is controlled directly by the communication IC
and is provided to cut-off power supply when some trouble occurs
with a grounded type load. The communication IC 1414 is connected
to a multiplex communication line 14010 via a communication IC
interface 1412. Further, the communication IC 1414 is connected to
the CPU 1413 so that it transmits and receives data necessary for
the power supply network via the multiplex communication line
14010. Detailed description of functions of the communication IC
1414 and the communication IC interface 1412 is omitted here. The
CPU 1413 includes a ROM (Read Only Memory) and a RAM (Random Access
Memory) provided therein, and control software for the ABS and
initial constants are stored in the ROM.
[0473] In the present embodiment, as loads of the ABS, the ABS
solenoids 1406, 1407 and 1408 (solenoid loads) and the ABS motor
(motor load) 14 are presumed, and while signals between the output
interface 1411 and the CPU 1413 include driving signals and state
detection signals of the individual loads described above, since
details of them are described in connection with the PCM
hereinabove, description of them is omitted here.
[0474] FIG. 103 illustrates a distribution situation of loads to
the FIM 1420 described above relating to the ABS. In the present
embodiment, the FIM supplies power to the ABS.
[0475] FIG. 104 illustrates a distribution situation of loads to an
IPM 1430 described above relating to the ABS. An ignition switch
1431 and a stop lamp switch 1432 provide input signals relating to
the ABS. An ABS alarm lamp 1433 is incorporated in the meter panel,
and driving data are transferred from the ABS to the IMP via the
BCM.
[0476] FIG. 105 shows a conventional example of an ABS system
construction and illustrates wiring line reduction effects by the
present invention. Since an ignition switch signal is fetched by
the BCM and transmitted by multiplex communication, wiring lines
relating to the ignition switch 1431 can be reduced. Since the ABS
receives supply of power from the FIM and an over-current state of
the ABS is supervised by the FIM, fuses 1442, 1443, 1444 and 1446
on the upstream can be reduced. Simultaneously, the necessity for
laying supply lines from the battery to the ABS via the fuse box in
the compartment is eliminated and wiring lines can be reduced as
much. Wiring lines for backing up the battery can be eliminated by
transmitting data necessary for backing up when power supply to the
ABS is cut-off to the BCM by multiplex communication as hereinafter
described. Since the driving element of the output interface can be
used in substitution for an ABS motor relay 1445 and an ABS
actuator relay 1447, they can be abandoned. Since signals are
transferred by multiplex communication via the IPM as hereinafter
described, the necessity for laying wiring lines individually for
the ABS alarm lamp 1433 and the stop lamp switch 1432 is
eliminated, and wiring lines can be reduced. While a vehicle speed
pulse signal 1440 is outputted from the vehicle speed sensor
mounted on the transmission, since, in the present invention, it is
produced by the ABS control module and transmitted to another
control unit by multiplex communication, relating wiring lines and
sensors are unnecessary. Since also self diagnosis 1441 is executed
by multiplex communication, wiring lines for the same can be
reduced similarly.
[0477] FIG. 106 illustrates a basic control flow of the ABS of the
present invention. After power is made available by the FIM,
processing is started from a reset state 1450. After the resetting,
the processing advances to initialization processing 1451, by which
initialization of the entire system is performed. Then, the
processing advances to brake control processing 1452, by which
brake hydraulic pressure control is performed based on input
information of various sensors. Then, the processing advances to
self diagnosprocesses 1453, by which self diagnosis of sensors and
actuators in the system is performed. Thereafter, the processing
advances to transmit data writing processing 1454, by which data to
be transmitted from the ABS to another control unit is written into
the communication IC. By discrimination processing 1455, it is
discriminated whether or not the ignition key switch is in an off
state, and if the key is in an off state, then the processing
advances to ending processing 1456, but if the key switch is an on
state, then the processing advances to the brake control processing
1452. By the ending processing 1456, transfer processing of the
backup data is performed. After the data transfer is completed, the
processing advances to an end state 1457 to make preparations for
cut-off of power supply by the FIM. Since the initialization
processing 1451 and the ending processing 1456 in the basic control
flow described above are same as those in the PCM control described
above, detailed description of them is omitted.
[0478] FIG. 107 illustrates a wheel speed calculation processing
flow. The present processing is started by timer interrupt. By
wheel speed sensor pulse count processing 1461, the number of
pulses of a wheel speed sensor after the preceding interrupt
processing till the current interrupt processing is measured. By a
wheel speed calculation processing, the numbers of rotations of the
wheels are calculated from the timer interrupt period and the pulse
number mentioned above to calculate the speeds of rotation. By
processing 1463, a pseudot vehicle body speed is calculated from
the wheel speeds for the four wheels thus obtained and is
determined as a vehicle speed. The processing returns from the
interrupt by processing 1464.
[0479] FIG. 108 illustrates details of the brake control processing
1452 in the basic control flow described above. By discrimination
processing 1471, it is discriminated whether or not the ABS has
some failed element, and if the ABS has some failed element, then
the processing advances to processing 14711, by which fail safe
processing is performed. In the fail safe processing, fail safe
processing determined in advance is executed in response to a
failure mode, and then the processing advances to ABS alarm lamp
lighting instruction processing 14712. By the ABS alarm lamp
lighting instruction processing 14712, the trouble occurrence bit
of the data to be transferred from the ABS to the BCM is set to
provide an alarm lamp lighting instruction. When the ABS has no
failed element, the processing advances to processing 1472. By the
processing 1472, slip ratios of the individual wheels are
calculated from the wheel speeds of the four wheels and the vehicle
body speed.
[0480] By processing 1473, in order to control the calculated slip
ratios described above to a fixed value, an ABS solenoid driving
mode is calculated. By processing 1474, the ABS solenoids are
driven based on the calculated solenoid driving mode. By processing
1475, the solenoid driving signals and the output state signal are
monitored and states of the load and the driving element in the
interface are supervised based on Table 11 given hereinabove. By
power supply cut-off processing (L) 1476, failure diagnosis of the
high side load (in this instance, the ABS solenoid) by the low side
driving element and incidental cut-off processing are performed
based on a result of the supervision described above. By processing
1477, an ABS motor driving mode is calculated using such data as
the wheel speeds described above. By processing 1478, the motor is
energized (driven) based on the calculated motor driving mode. By
processing 1479, the driving signals of the ABS motors and the
output state signal are monitored and states of the load and the
driving element in the output interface are supervised based on
Table 11 given hereinabove. By power supply cut-off processing (L)
14710, failure diagnosis of the high side load (in this instance,
the ABS motor) by the low side driving element and incidental
interruption processing are performed based on a result of the
supervision described above.
[0481] FIG. 109 illustrates details of the transmission data
writing processing 1454 in the basic control flow described
hereinabove. By processing 1481, in order to transmit vehicle speed
data to the individual control units simultaneously, a transmission
mode of the communication IC is designated to a functional address.
By processing 1482, the vehicle speed data for transmission is set
to the communication IC. By processing 1483, setting of the ABS
alarm lamp is written into the communication IC. By processing
1484, the power supply cut-off instruction bit of the ABS itself is
set and written into the communication IC. After the data are
written, the communication IC effects data transmission processing
to the designated transmission destination.
[0482] FIG. 110 illustrates a multiplex communication data receive
processing flow. Since the construction wherein external interrupt
occurs with the CPU when the communication IC receives data is
adopted, the present processing is started by external interrupt in
a state 1490. By discrimination processing 1491, it is
discriminated whether or not receive data is broadcast
communication data. When the receive data is broadcast
communication data, the processing advances to processing 1493, by
which ignition key switch position information is read in. Then by
processing 1494, a stop lamp switch state is read in. When the
receive data is not broadcast communication data, the processing
advances to discrimination processing 1492. When the transmission
destination is the self diagnosis apparatus, a diagnosis processing
command is read in by processing 1496, and corresponding self
diagnosprocesses is performed in the self diagnosprocesses in the
main routine.
[0483] FIG. 111 is a system diagram showing a construction of a
navigation system (hereinafter referred to as navig. system) for a
vehicle to which the power supply network of the present invention
is applied. A navig. unit 1500 receives various sensor signals and
displays a TV image or a position of the vehicle on a display unit
by a control method determined in advance. A TV tuner 1502
reproduces radio waves received by a TV antenna 1501 and outputs
them to the navig. unit 1500. A GPS receiver 1504 demodulates radio
waves received by a GPS antenna 1503, calculates the position of
the vehicle and outputs a result of the calculation to the navig.
unit 1500. A gyro sensor 1505 detects a turning angular velocity of
the vehicle body and outputs it to the navig. unit 1500. A CD-ROM
unit 1506 outputs map data stored in a CD-ROM in response to an
instruction from the navig. unit. A display unit 1508 displays a TV
image mentioned above or a map upon navigation. An operation switch
1507 selects an operation mode or the like of the navig. system. A
power supply line 1509 is part of the power supply network of the
present invention, and supplies power to the navig. system itself
and power to the load 1508 from the BCM. A multiplex communication
line 15010 is part of the power supply network similarly and is
provided to effect communication with a control unit such as the
BCM.
[0484] FIG. 112 shows a detailed diagram of an internal
construction of the navig. module 1500. A signal from the TV tuner
is sent to an output interface 1512 through a tuner interface 1510.
An input signal from the operation switch 1507 is converted by a
digital input interface 1511 so that it has a level with which it
can be processed readily by a CPU, and is fetched into a CPU 1513.
Another CPU 1514 calculates a current position from data of the GPS
receiver 1504 and the gyro sensor 1505 and transfers the same to
the CPU 1513. The CPU 1513 retrieves, based on the self position
data from the CPU 1514, map data stored in the CD-ROM unit 1506 and
outputs corresponding map information to the output interface 1512.
The output interface 1512 outputs a TV tuner image or a map image
to the display unit in response to a control signal of the CPU
1514. Powers supplied from the BCM include power to be supplied to
a constant voltage power supply 1518 for a communication IC 1516 in
the navig. system, and power to be supplied to another constant
voltage power supply 1517, the input interface 1511 and the output
interface 1512 via a power supply cut-off switch 1519. The constant
voltage power supply 1518 is a constant voltage power supply
generation circuit for exclusive use for the communication IC and
is normally energized unless power supply from the BCM is cut-off.
The constant voltage power supply 1517 supplies power to the CPU
1513 and the CPU 1514. The power supply cut-off switch 1519 is
controlled directly by the communication IC and is provided in
order to cut-off power supply when some trouble occurs with a
grounded type load. The communication IC 1516 is connected to the
multiplex communication line 15010 via a communication IC interface
1515. Further, the communication IC 1516 is connected to the CPU
1513 so that it transmits and receives data necessary for the power
supply network via the multiplex communication line 15010. Detailed
description of functions of the communication IC 1516 and the
communication IC interface 1515 is omitted here. The CPU 1513
includes a ROM (Read Only Memory) and a RAM (Random Access Memory)
provided therein, and control software for the navigation system
and initial constants are stored in the ROM.
[0485] FIG. 113(A) illustrates a distribution situation of loads to
an IPM 1520 described above relating to the navigation system. An
ignition switch 1521 and a parking brake switch 1522 provide input
signals relating to the navigation system. Driving data for them
are transferred from the navig. system to the IPM via the BCM.
[0486] FIG. 113(B) illustrates a distribution situation of loads to
a BCM 1530 described above relating to the navigation system. In
the present embodiment, the BCM supplies power to the navigation
system.
[0487] FIG. 114 shows a conventional example of a navigation system
construction and illustrates wiring line reduction effects by the
present invention. Since an ignition switch signal is fetched by
the BCM and transmitted by multiplex communication, wiring lines
relating to the ignition switch 1522 can be reduced. Since the
navig. system receives supply of power from the BCM and an
over-current state is supervised by the BCM, fuses 1542 and 1543 on
the upstream can be reduced. Simultaneously, the necessity for
laying power supply lines from the battery to the navig. system via
the fuse box in the compartment is eliminated, and wiring lines can
be reduced as much. The necessity for power supply lines for
backing up the battery is eliminated by transferring data necessary
for the backing up when power supply to the navigation system is
cut-off by multiplex communication to the BCM as hereinafter
described. Since signals are transferred by multiplex communication
through the IPM as described above, the parking brake switch 1522
need not be wired individually and wiring lines can be reduced.
Since a vehicle speed pulse signal 1540 is produced by the ABS and
transmitted by multiplex communication and also self diagnosis 1530
is executed by multiplex communication, wiring lines for them can
be reduced similarly.
[0488] FIG. 115 illustrates a basic control flow of the navigation
system of the present invention by the CPU 1513. After power is
made available by the BCM, processing is started from a reset state
1550. After the resetting, the processing advances to
initialization processing 1551, by which initialization of the
entire system is performed. Then, the processing advances to
processing 1552, by which a current position calculated based on a
GPS (Global Positioning System) signal and a gyro signal is
converted into data which can be processed readily. By processing
1553, map data corresponding to the current position is read out
from the CD-ROM. By discrimination processing 1554, it is selected
by means of the operation switch whether a TV image or a navig.
image is to be displayed. When a TV image is to be displayed, the
processing advances to processing 1555, by which a TV image is
displayed. When a navig. image is to be displayed, the processing
advances to processing 1556, by which a map is displayed.
Thereafter, the processing advances to self diagnosprocesses 1557,
by which self diagnosis of sensors and actuators in the system is
performed. Then, the processing advances to transmit data writing
processing 1558, by which data to be transmitted from the navig.
system to another control unit is written into the communication
IC. By discrimination processing 1559, it is discriminated whether
or not the ignition key switch is in an off state, and if the key
switch is in an off state, then the processing advances to ending
processing 15510, but if the key switch is in an on state, then the
processing advances to processing 1552. By the ending processing
15510, transfer processing of the backup data is performed. After
the data transfer is completed, the processing advances to an end
state 15511 to make preparations for interruption of power by the
BCM. Since the initialization processing 1551 and the ending
processing 15510 in the basic control flow described above are same
as those in the PCM control described above, detailed description
of them is omitted.
[0489] FIG. 116 illustrates details of the transmit data writing
processing 1558 in the basic control flow described
hereinabove.
[0490] By processing 1561, a physical address is set, and by
processing 1562, a transmission destination address is set to the
BCM. By processing 1563, the power supply cut-off instruction bit
of the navig. system itself is set and written into the
communication IC. After the data is written, the communication IC
effects data transmission processing to the designated transmission
destination.
[0491] FIG. 117 illustrates a multiplex communication data receive
processing flow. When the communication IC receives data, external
interrupt occurs with the CPU, and the present processing is
started by the interrupt. By discrimination processing 1571, 1574
and 1576, the transmission origination of the receive data is
discriminated. When the transmission origination is the BCM, the
processing advances to processing 1572. When the transmission
origination is the ABS, the processing advances to processing 1574.
When the transmission origination is the self diagnosis apparatus,
the processing advances to processing 1577.
[0492] By the processing 1572, ignition key switch position
information is read in, and by the processing 1573, a parking brake
switch state is read in. Further, by the processing 1575, vehicle
speed data are read in. By the processing 1577, a diagnosprocesses
command is read in, and corresponding self diagnosis processing is
performed in the self diagnosprocesses in the main routine.
Industrial Applicability
[0493] As described above, while a power supplying apparatus and
method and a semiconductor circuit apparatus or an intensive wiring
apparatus for use with the power supplying apparatus and method
according to the present invention are described above in
connection with the embodiments for an automobile, the basic
techniques can be applied not only to automobiles, but also widely
to, for example, electric cars, airplanes, marine vessels and other
vehicles wherein a large number of electric loads are located far
from a power supply.
* * * * *