U.S. patent application number 10/290131 was filed with the patent office on 2003-08-07 for method for enabling power-saving mode.
Invention is credited to Chang, Yu-Wei.
Application Number | 20030149903 10/290131 |
Document ID | / |
Family ID | 27657711 |
Filed Date | 2003-08-07 |
United States Patent
Application |
20030149903 |
Kind Code |
A1 |
Chang, Yu-Wei |
August 7, 2003 |
Method for enabling power-saving mode
Abstract
A method for enabling a power-saving mode for an electronic
apparatus is disclosed. The electronic apparatus is electrically
connected to a peripheral device via a peripheral interface device.
The method includes steps of comparing a first input value with a
first reference value, determining a transmission index according
to a comparing result of the first input value and the first
reference value, and having the peripheral interface device enter a
power-saving mode when the transmission index indicates an inactive
transmission state.
Inventors: |
Chang, Yu-Wei; (Taipei,
TW) |
Correspondence
Address: |
MADSON & METCALF
GATEWAY TOWER WEST
SUITE 900
15 WEST SOUTH TEMPLE
SALT LAKE CITY
UT
84101
|
Family ID: |
27657711 |
Appl. No.: |
10/290131 |
Filed: |
November 7, 2002 |
Current U.S.
Class: |
713/300 |
Current CPC
Class: |
G06F 1/3215
20130101 |
Class at
Publication: |
713/300 |
International
Class: |
G06F 001/26 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 1, 2002 |
TW |
091101721 |
Claims
What is claimed is:
1. A method for enabling a power-saving mode for an electronic
apparatus, said electronic apparatus being electrically connected
to a peripheral device via a peripheral interface device, said
method comprising steps of: comparing a first input value with a
first reference value; determining a transmission index according
to a comparing result of said first input value and said first
reference value; and having said peripheral interface device enter
a power-saving mode when said transmission index indicates an
inactive transmission state.
2. The method according to claim 1 wherein said first input value
is a counting value generated in response to a system clock.
3. The method according to claim 1 wherein said first reference
value is a constant value.
4. The method according to claim 1 wherein said transmission index
includes a plurality of transmission-state bits.
5. The method according to claim 4 wherein said plurality of
transmission-state bits correspond to an asynchronous request
transmit mode, an asynchronous response transmit mode, an
asynchronous request receive mode, an asynchronous response receive
mode, isochronous transmit modes and isochronous receive modes.
6. The method according to claim 4 wherein said inactive
transmission state is determined when all said transmission-state
bits are in disable states.
7. The method according to claim 1 further comprising a step of
resetting said first input value when said inactive transmission
state is determined and said peripheral interface device enters
said power-saving mode.
8. The method according to claim 1 wherein said transmission index
indicating said inactive transmission state is generated when said
comparing result indicates that said first input value
substantially equals to said first reference value.
9. The method according to claim 8 wherein said transmission index
indicating an active transmission state is generated when said
first input value is different from said first reference value.
10. The method according to claim 9 wherein said first input value
is updated to repeat the comparing step when said transmission
index indicates said active transmission state.
11. The method according to claim 9 wherein said active
transmission state is determined when at least one of
transmission-state bits included in said transmission index are in
an enable state.
12. The method according to claim 1 wherein said power-saving mode
includes at least two power-saving stages.
13. The method according to claim 1 further comprising steps of:
detecting a status of a second input value when said first input
value is substantially equal to said first reference value; and
prohibiting said peripheral interface device from entering said
power-saving mode when said second input value is in a specified
status.
14. The method according to claim 13 wherein said second input
value is a flag and said specified status is one of a true and a
false status.
15. The method according to claim 1 further comprising steps of:
comparing a third input value with a third reference value when
said first input value is different from said first reference
value; and determining a port disable mode and having said
peripheral interface device enter said power-saving mode in
response to a comparing result indicating that said third input
value is substantially equal to said third reference value.
16. The method according to claim 15 wherein said third input value
is a counting value generated in response to a system clock, and
said third reference value is a constant value.
17. The method according to claim 16 wherein said third input value
is zeroed when said third input value is substantially equal to
said third reference value, and accumulatively updated when said
third input value is different from said third reference value.
18. The method according to claim 15 wherein said port disable mode
is determined according to a bias bit and a connection bit.
19. The method according to claim 18 wherein said port disable mode
is determined when at least one of said bias bit and said
connection bit are under a disable state.
20. The method according to claim 19 wherein a port enable mode is
determined when said bias bit and said connection bit are both
under an enable state.
21. The method according to claim 15 wherein said peripheral
interface device includes a plurality of ports, and said
power-saving mode is entered when all of said ports are under said
port disable mode.
22. The method according to claim 15 further comprising steps of:
detecting a status of a fourth input value when said third input
value is substantially equal to said third reference value; and
prohibiting said peripheral interface device from entering said
power-saving mode when said fourth input value is in a specified
status.
23. The method according to claim 22 wherein said fourth input
value is a flag and said specified status is one of a true and a
false status.
24. A method for enabling a power-saving mode for an electronic
apparatus, said electronic apparatus being electrically connected
to a peripheral device via a peripheral interface device with at
least one port, said method comprising steps of: comparing a first
input value with a first reference value; determining a port
situation index according to a comparing result of said first input
value and said first reference value; and having said peripheral
interface device enter a power-saving mode when said port situation
index indicates an inactive transmission state.
25. The method according to claim 24 wherein said port situation
index is determined according to a bias bit and a connection
bit.
26. The method according to claim 25 wherein said port situation
index indicates a port disable mode when at least one of said bias
bit and said connection bit are under a disable state.
27. The method according to claim 26 wherein said power-saving mode
is entered when all of said ports of said peripheral interface
device are under said port disable mode.
28. The method according to claim 25 wherein said port situation
index indicates a port enable mode when said bias bit and said
connection bit are both under an enable state.
29. The method according to claim 24 further comprising steps of:
detecting a status of a second input value when said first input
value is substantially equal to said first reference value; and
prohibiting said peripheral interface device from entering said
power-saving mode when said second input value is in a specified
status.
30. The method according to claim 29 wherein said second input
value is a flag and said specified status is one of a true and a
false status.
31. The method according to claim 24 further comprising steps of:
comparing a third input value with a third reference value; and
determining a transmission inactive mode and having said peripheral
interface device enter said power-saving mode in response to a
comparing result indicating that said third input value and said
third reference value.
32. The method according to claim 31 wherein said first and third
input values are counting values generated in response to a system
clock, and said first and third reference values are constant
values.
33. The method according to claim 31 wherein said transmission
inactive mode is determined when all transmission-state bits are in
a disable state.
34. The method according to claim 31 further comprising steps of:
detecting a status of a fourth input value when said third input
value is substantially equal to said third reference value; and
prohibiting said peripheral interface device from entering said
power-saving mode when said fourth input value is in a specified
status.
35. The method according to claim 34 wherein said fourth input
value is a flag and said specified status is one of a true and a
false status.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method for enabling a
power-saving mode, and more particularly to a method for enabling a
power-saving mode of a peripheral interface device.
BACKGROUND OF THE INVENTION
[0002] With the increasing number of peripheral devices connected
thereto, the power consumption of an electronic apparatus
increases. Especially for a portable electronic apparatus, e.g. a
portable computer or a cellular phone, a battery which has limited
power capacity is generally used as the power source. Therefore, it
is an important issue to prolong the standby period of the
battery.
[0003] For example, a notebook computer is expandable by connecting
thereto various peripheral devices via a peripheral interface
device, such as IEEE 1394 interface card, with a plurality of
expansion I/O ports. It is apparent that the power consumption of
the notebook computer increases with the expansion functions
applied thereto. Thus, the standby period of the battery decreases
accordingly.
[0004] Therefore, the present invention is developed to deal with
the above situations encountered in the prior art.
SUMMARY OF THE INVENTION
[0005] An object of the present invention is to provide a method
for reducing the power consumption of an electronic apparatus by
allowing the electronic apparatus to enter a power-saving mode at
proper timing.
[0006] Another object of the present invention is to provide a
method for prolonging the standby period of a portable electronic
apparatus by allowing the portable electronic apparatus to enter a
power-saving mode when the peripheral interface device is not under
a data-tranceiving state.
[0007] According to an aspect of the present invention, there is
provided a method for enabling a power-saving mode for an
electronic apparatus. The electronic apparatus is electrically
connected to a peripheral device via a peripheral interface device.
The method includes steps of comparing a first input value with a
first reference value, determining a transmission index according
to a comparing result of the first input value and the first
reference value, and having the peripheral interface device enter a
power-saving mode when the transmission index indicates an inactive
transmission state.
[0008] Preferably, the first input value is a counting value
generated in response to a system clock.
[0009] Preferably, the first reference value is a constant
value.
[0010] Preferably, the transmission index includes a plurality of
transmission-state bits. For example, the plurality of
transmission-state bits correspond to an asynchronous request
transmit mode, an asynchronous response transmit mode, an
asynchronous request receive mode, an asynchronous response receive
mode, isochronous transmit modes or isochronous receive modes.
Preferably, the inactive transmission state is determined when all
of the transmission-state bits are in disable states.
[0011] Preferably, the method further includes a step of resetting
the first input value when the inactive transmission state is
determined and the peripheral interface device has entered the
power-saving mode.
[0012] Preferably, the transmission index indicating the inactive
transmission state is generated when the comparing result indicates
that the first input value substantially equals to the first
reference value. Preferably, The transmission index indicating an
active transmission state is generated when the first input value
is different from the first reference value. The first input value
is preferably updated to repeat the comparing step when the
transmission index indicates the active transmission state. The
active transmission state is preferably determined when at least
one of transmission-state bits included in the transmission index
are in an enable state.
[0013] Preferably, the power-saving mode includes at least two
power-saving stages.
[0014] Preferably, the method further includes steps of detecting a
status of a second input value when the first input value is
substantially equal to the first reference value, and prohibiting
the peripheral interface device from entering the power-saving mode
when the second input value is in a specified status. Preferably,
the second input value is a flag and the specified status is one of
a true and a false status.
[0015] Preferably, the method further includes steps of comparing a
third input value with a third reference value when the first input
value is different from the first reference value, and determining
a port disable mode and having the peripheral interface device
enter the power-saving mode in response to a comparing result
indicating that the third input value is substantially equal to the
third reference value. The third input value is preferably a
counting value generated in response to a system clock, and the
third reference value is a constant value. Preferably, the third
input value is zeroed when the third input value is substantially
equal to the third reference value, and accumulatively updated when
the third input value is different from the third reference
value.
[0016] Preferably, the port disable mode is determined according to
a bias bit and a connection bit. Preferably, a port disable mode is
determined when at least one of the bias bit and the connection bit
are under a disable state. Another port enable mode is preferably
determined when the bias bit and the connection bit are both under
an enable state.
[0017] Preferably, the peripheral interface device includes a
plurality of ports, and the power-saving mode is entered when all
of the ports are under the port disable mode.
[0018] Preferably, the method further includes steps of detecting a
status of a fourth input value when the third input value is
substantially equal to the third reference value, and prohibiting
the peripheral interface device from entering the power-saving mode
when the fourth input value is in a specified status. Preferably,
the fourth input value is a flag and the specified status is one of
a true and a false status.
[0019] According to another aspect of the present invention, there
is provided a method for enabling a power-saving mode for an
electronic apparatus. The electronic apparatus is electrically
connected to a peripheral device via a peripheral interface device
with at least one port. The method includes steps of comparing a
first input value with a first reference value, determining a port
situation index according to a comparing result of the first input
value and the first reference value, and having the peripheral
interface device enter a power-saving mode when the port situation
index indicates an inactive transmission state.
[0020] Preferably, the port situation index is determined according
to a bias bit and a connection bit. In a case, the port situation
index preferably indicates a port disable mode when at least one of
the bias bit and the connection bit are under a disable state.
Preferably, the power-saving mode is entered when all of the ports
of the peripheral interface device are under the port disable mode.
In another case, the port situation index preferably indicates a
port enable mode when the bias bit and the connection bit are both
under an enable state.
[0021] Preferably, the method further includes steps of detecting a
status of a second input value when the first input value is
substantially equal to the first reference value, and prohibiting
the peripheral interface device from entering the power-saving mode
when the second input value is in a specified status. The second
input value is preferably a flag and the specified status is one of
a true and a false status.
[0022] Preferably, the method further includes steps of comparing a
third input value with a third reference value, and determining a
transmission inactive mode and having the peripheral interface
device enter the power-saving mode in response to a comparing
result indicating that the third input value and the third
reference value. Preferably, the first and third input values are
counting values generated in response to a system clock, and the
first and third reference values are constant values. The
transmission inactive mode is preferably determined when all
transmission-state bits are in a disable state. Preferably, the
method further includes steps of detecting a status of a fourth
input value when the third input value is substantially equal to
the third reference value, and prohibiting the peripheral interface
device from entering the power-saving mode when the fourth input
value is in a specified status.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The present invention may best be understood through the
following description with reference to the accompanying drawings,
in which:
[0024] FIG. 1 is a functional block diagram illustrating a
preferred embodiment of a method for enabling a power-saving mode
of a peripheral interface device according to the present
invention;
[0025] FIGS. 2A-2D are flowcharts illustrating a preferred
embodiment of a method for enabling a power-saving mode of a
peripheral interface device according to the present invention;
[0026] FIG. 2E is a detailed flowchart illustrating the step of P26
in FIG. 2D;
[0027] FIGS. 3A-3D are flowcharts illustrating another preferred
embodiment of a method for enabling a power-saving mode of a
peripheral interface device according to the present invention;
and
[0028] FIG. 3E is a detail flowchart illustrating the step of E18
in FIG. 3B.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] The present invention will now be described more
specifically with reference to the following embodiments. It is to
be noted that the following descriptions of preferred embodiments
of this invention are presented herein for purpose of illustration
and description only; it is not intended to be exhaustive or to be
limited to the precise form disclosed.
[0030] Please refer to FIG. 1. A system 10 includes an interface
connection port L electrically connected to a peripheral interface
device 20 via a connecting wire 30. The peripheral interface device
20 includes an interface controller 21 and a plurality of expansion
ports (not shown) for connecting to a plurality of the peripheral
devices (not shown).
[0031] For easily understanding the present invention, an
exemplified embodiment is given herein. In this embodiment, the
peripheral interface device 20 is an IEEE 1394 peripheral interface
card and provides a plurality of transmission modes including an
asynchronous request transmit mode, an asynchronous response
transmit mode, an asynchronous request receive mode, an
asynchronous response receive mode, isochronous transmit modes and
isochronous receive modes. For each transmission mode, a context
control set register is provided, disposed in the peripheral
interface card 20, for storing a corresponding transmission control
context. In other words, the interface controller 21 of the
peripheral interface card 20 transmits the transmission control
contexts Ic0.about.Icn corresponding to the transmission modes,
respectively, into an interface information storage region Mi of a
memory M. Each of the transmission control contexts Ic0.about.Icn
includes a corresponding transmission-state bit. Hence, there are a
plurality of transmission-state bits Bit0.about.Bitn, representing
the plurality of transmission modes, respectively.
[0032] Each of the transmission-state bits Bit0.about.Bitn includes
a disable state and an enable state. When all of the
transmission-state bits Bit0.about.Bitn are in the disable states,
it represents that it is in an inactive transmission state. When at
least one of the transmission-state bits Bit0.about.Bitn is in its
enable state, an active transmission state is determined.
[0033] In addition, the port situation indices Ip0.about.Ipm, the
bias-state bits Ib0.about.Ibm and the connection-state bits
It0.about.Itm are stored in respective registers of the peripheral
interface card 20 and used to determine whether the expansion ports
are in disable or enable states.
[0034] When the bias-state bit and the connection-state bit are
both under enable states, it means the bias and the connection
states of the expansion port to the peripheral device is normal.
Thus, the port situation index of the expansion port indicates a
port enable mode. When the bias-state bit and the connection-state
bit are both under disable states, it means the expansion port is
not connected to any peripheral device. Thus, the port situation
index of the expansion port indicates a port disable mode. When the
bias-state bit is under its enable state but the connection-state
bit is under its disable state, the connection of the expansion
port to the peripheral device is determined to be abnormal. Thus,
the port situation index of the expansion port indicates a port
disable mode. When the bias-state bit is under its disable state
but the connection-state bit is under its enable state, it means
the expansion port has an abnormal bias. Thus, the port situation
index of the expansion port indicates a port disable mode. The port
is disabled in response to a command from the control unit 11, the
peripheral interface device 20 or a user.
[0035] The power mode index Ips of the peripheral interface card 20
is transmitted to the interface information storage region Mi by
the interface controller 21 to be realized by the control unit 11.
The control unit 11 changes the power mode index Ips in the
interface information storage region Mi according to the
transmission-state bits Bit0.about.Bitn and the port situation
indices Ip0.about.Ipm. The power mode index Ips indicates one of no
special power-saving mode D0, a primary power-saving mode D1, an
intermediate power-saving mode D2 and a highly power-saving mode
D3. For example, when the transmission-state bits Bit0.about.Bitn
are all under disable states or when all the port situation indices
Ip0.about.Ipm are under disable states, the power mode index Ips
indicates the highly power-saving mode D3.
[0036] For further describing the present invention, a method for
enabling a power-saving mode of a peripheral interface device
according to the present invention is illustrated with reference to
the flowcharts of FIGS. 2A-2D. First of all, initial values of a
first input value C.sub.C, a first reference value
C.sub.C.sub..sub.--.sub.CHK, a second input value Flagc, a third
input value C.sub.P, a third reference value
C.sub.P.sub..sub.--.sub.CHK and a fourth input value Flagp are set
up in Step P12. In this embodiment, both of the first and third
input values C.sub.C and C.sub.P are counting values, and the first
and third reference values C.sub.C.sub..sub.--.sub.CHK and
C.sub.P.sub..sub.--.sub.- CHK are constant values. Both the first
and third input values C.sub.C and C.sub.P, however, can also be
interrupt signals generated from the peripheral interface device
20, and the first and third reference values
C.sub.C.sub..sub.--.sub.CHK and C.sub.P.sub..sub.--.sub.CHK can be
the interrupt signals under specific states. The second and fourth
input values Flagc and Flagp are flags. While a first state of the
flag indicates a true status, a second state of the flag indicates
a false status.
[0037] In response to a system clock of a system 10, counters work
to generate the first and third input values C.sub.C and C.sub.P,
respectively, referring to Step P13. The control unit 11 uses a
timer of a basic input/output system (BIOS) of the system 10 to
provide a counting clock for those counters. The counters, which
can be disposed in the control unit 11, are up-counting,
down-counting or cyclic counters.
[0038] In Steps P14 and P15, the first input value C.sub.c is
inputted and compared with the first reference value
C.sub.C.sub..sub.--.sub.CHK. When the first input value C.sub.C is
substantially equal to the first reference value
C.sub.C.sub..sub.--.sub.CHK, go to Steps P16 and P17 to input the
second input value Flagc, and determine whether the second input
value Flagc is in a true status. Otherwise, go to Step P22 (see
FIG. 2C) to monitor port situations. Referring back to Step P17, if
the second input value Flagc is in the true status, go to Steps P18
and P19 (see FIG. 2B) to input the transmission-state bits
Bit0.about.Bitn from the interface information storage region Mi
and determine their transmission states. If all of the
transmission-state bits Bit0.about.Bitn are under
transmission-disable states, the control unit 11 changes the power
mode index Ips in the interface information storage region Mi, and
the interface controller 21 has the peripheral interface device 20
enter the highly power-saving mode D3 (Step P20, FIG. 2B).
Otherwise, if the transmission-state bits Bit0.about.Bitn are not
all under disable states, the power mode index Ips is variously
re-entered by the control unit 11 (Step P34, FIG. 2B). For example,
when there are three of the transmission-state bits Bit0.about.Bitn
remaining in transmission-enable states, the power mode index Ips
is changed to a value indicating the intermediate power-saving mode
D2 of the peripheral interface device 20. Further, the peripheral
interface device 20 enters a primary poser-saving mode D1 in
response to the change of power mode index Ips when there is four
of the transmission-state bits Bit0.about.Bitn remaining in
transmission-enable states. More than four transmission-state bits
Bit0.about.Bitn remaining in transmission-enable states correspond
to another power mode index value and result in the no power-saving
mode D0. After either of the power-saving modes D0, D1, D2 and D3,
the first input value C.sub.C is initialized by resetting the
associated counter, as indicated by Step P21.
[0039] Please go back to Step P17 in FIG. 2A again. If the second
input value Flagc is not in the true status, i.e. it is in a false
status, go to Steps P30 and P31 where the power index Ips in the
interface information storage region Mi is inputted to determine
whether the peripheral interface device 20 is in the no
power-saving mode D0. If it is, the control unit 11 resets the the
counter and initializes the first input value C.sub.C. On the
contrary, if it is not, go to Step P33 where the control unit 11
changes the power index Ips to to force the peripheral interface
device 20 to enter the no power-saving mode D0, and then resets the
counting value C.sub.C. It is understood that the input value flagc
allows the user to decide whether the power-saving function is to
be entered or not.
[0040] After the power-saving functions in response to the data
transmission states and/or the input value flagc are determined,
the counting value C.sub.C is reset, and Step P22 (FIG. 2C) where
another input value C.sub.P is inputted is executed. The third
input value C.sub.P is compared with the third reference value
C.sub.P.sub..sub.--.sub.CHK in Step P23. If the comparing result
indicates that the input value C.sub.P is different from the
reference value C.sub.P.sub..sub.--.sub.CHK, the procedure is back
to Step P13 (FIG. 2A), counting up/down to generate new input
values C.sub.C and C.sub.P. On the contrary, if the comparing
result indicates that the input value C.sub.P is substantially
equal to the reference value C.sub.P.sub..sub.--.sub.CHK, another
input value Flagp is inputted and determined whether to be in the
true status. When the input value Flagp indicates a false status,
go to Step P35 where the port situation indices Ip0.about.Ipm are
inputted and the port situations are determined. If all the port
situation indices reveal disable states, the control unit 11 resets
the input value C.sub.P in Step P37 and the procedure goes back to
Step P13. Otherwise, all the port situation indices Ip0.about.Ipm
are forced to the disable states before the input value C.sub.P is
reset and Step P13 is executed. On the other hand, when the input
value Flagp indicates the true status in Step P25, the port
situation indices Ip0.about.Ipm are inputted and discriminated to
be in enable states or disable states in Step P26. If the port
situation indices Ip0.about.Ipm are all determined to be under the
disable states in Step P27, the control unit 11 changes the power
mode index Ips, and the interface controller 21 has the peripheral
interface device 20 enter the highly power-saving mode D3 (Step
P28, FIG. 2D). Otherwise, if the port situation indices
Ip0.about.Ipm are not all under disable states in Step P27, the
power mode index Ips is variously re-entered by the control unit 11
(Step P39, FIG. 2D). For example, when there are three of the port
situation indices Ip0.about.Ipm remaining in transmission-enable
states, the power mode index Ips is changed to a value indicating
the intermediate power-saving mode D2 of the peripheral interface
device 20. Further, the peripheral interface device 20 enters a
primary poser-saving mode D1 in response to the change of power
mode index Ips when there is four of the port situation indices
Ip0.about.Ipm remaining in transmission-enable states. More than
four port situation indices Ip0.about.Ipm remaining in
transmission-enable states correspond to another power mode index
value and result in the no power-saving mode D0. After either of
the power-saving modes D0, D1, D2 and D3, the input value C.sub.P
is initialized by resetting the associated counter. It is
understood that the input value flagp allows the user to decide
whether the power-saving function is to be entered or not. After
the power-saving functions in response to the port utilization
states and/or the input value flagp are determined, the counting
value C.sub.P is reset, and Step P13 (FIG. 2A) where new input
values C.sub.C and C.sub.P are generated and inputted is executed,
thereby continuousely monitoring and optimizing the power
consumption of the peripheral interface device.
[0041] Preferably, the step P26 for discriminating the port
situation indices Ip0.about.Ipm is executed by the sub-steps P261
to P264 as shown in FIG. 2E. First of all, the port situation
indices Ip0.about.Ipm are inputted. Then, the bias-state bit and
the connection-state bit corresponding to each of the port
situation indices Ip0.about.Ipm are determined to be in enable or
disable states. When the bias-state bit and connection-state bit
are both under enable states, which means the bias of the
corresponding expansion port of the peripheral interface device 20
is in a normal state and the connection of the expansion port to
the peripheral device is perfect, the port situation index
associated with the expansion port is discriminated to be under the
enable state. Otherwise, the port situation index is discriminated
to be under the disable state.
[0042] FIGS. 3A-3D are flowcharts illustrating another method for
enabling a power-saving mode of a peripheral interface device
according to the present invention. In this method, the port
situation is detected prior to the transmission state.
[0043] First of all, initial values of a first input value C.sub.P,
a first reference value C.sub.P.sub..sub.--.sub.CHK, a second input
value Flagp, a third input value C.sub.C, a third reference value
C.sub.C.sub..sub.--.sub.CHK and a fourth input value Flagc are set
up in Step E12. In this embodiment, both of the first and third
input values C.sub.P and C.sub.C are counting values, and the first
and third reference values C.sub.P.sub..sub.--.sub.CHK and
C.sub.C.sub..sub.--.sub.- CHK are constant values. Both the first
and third input values C.sub.P and C.sub.C, however, can also be
interrupt signals generated from the peripheral interface device
20, and the first and third reference values
C.sub.P.sub..sub.--.sub.CHK and C.sub.C.sub..sub.--.sub.CHK can be
the interrupt signals under specific states. The second and fourth
input values Flagp and Flagc are flags. While a first state of the
flag indicates a true status, a second state of the flag indicates
a false status.
[0044] In response to a system clock of a system 10, counters work
to generate the first and third input values C.sub.P and C.sub.C,
respectively, referring to Step E13. In Steps E14 and E15, the
first input value C.sub.P is inputted and compared with the first
reference value C.sub.P.sub..sub.--.sub.CHK. If the first input
value C.sub.P is substantially equal to the first reference value
C.sub.P.sub..sub.--.sub.- CHK, go to Steps E16 and E17 to input the
second input value Flagp, and determine whether the second input
value Flagp is true or not. Otherwise, go to Step E22 (see FIG. 3C)
to monitor transmission states. Referring back to Step E17, if the
second input value Flagp is true, go to Steps E18 and E19 (see FIG.
3B) to input the port situation indices Ip0.about.Ipm from the
interface information storage region Mi and determine their port
states. If all of the port situation indices Ip0.about.Ipm indicate
disable states, the control unit 11 changes the power mode index
Ips in the interface information storage region Mi, and the
interface controller 21 has the peripheral interface device 20
enter the highly power-saving mode D3 (Step E20, FIG. 3B).
Otherwise, the power mode index Ips is variously re-entered by the
control unit 11 (Step E34, FIG. 3B). For example, when there are
three of the port situation indices Ip0.about.Ipm remaining in
transmission-enable states, the power mode index Ips is changed to
a value indicating the intermediate power-saving mode D2 of the
peripheral interface device 20. Further, the peripheral interface
device 20 enters a primary poser-saving mode D1 in response to the
change of power mode index Ips when there is four of the port
situation indices Ip0.about.Ipm remaining in transmission-enable
states. More than four port situation indices Ip0.about.Ipm
remaining in transmission-enable states correspond to another power
mode index value and result in the no power-saving mode D0. After
either of the power-saving modes D0, D1, D2 and D3, the first input
value C.sub.P is initialized by resetting the associated counter,
as indicated by Step E21.
[0045] Please go back to Step E17 in FIG. 3A again. If the second
input value Flagp is not true, i.e. it is false, go to Steps E30
and E31 to monitor the port situation indices Ip0.about.Ipm. If the
port situation indices Ip0.about.Ipm are all in disable states, the
control unit 11 resets the the counter and initializes the first
input value C.sub.P. On the contrary, if the port situation indices
Ip0.about.Ipm are not all in disable states, go to Step E33 to have
the peripheral interface device enter the no power-saving mode D0,
and then resets the counting value C.sub.P. It is understood that
the input value flagp allows the user to decide whether the
power-saving function is to be entered or not.
[0046] After the power-saving functions in response to the port
situations and/or the input value flagp are determined, the
counting value C.sub.P is reset, and Step E22 (FIG. 3C) where
another input value C.sub.C is inputted is executed. The third
input value C.sub.C is compared with the third reference value
C.sub.C.sub..sub.--.sub.CHK in Step E23. If the comparing result
indicates that the input value C.sub.P is different from the
reference value C.sub.P.sub..sub.--.sub.CHK, the procedure is back
to Step E13 (FIG. 3A), i.e. counting up/down to generate new input
values C.sub.C and C.sub.P. On the contrary, if the comparing
result indicates that the input value C.sub.C is substantially
equal to the reference value C.sub.C.sub..sub.--.sub.CHK, another
input value Flagc is inputted and determined whether to be true.
When the input value Flagc indicates a false status, go to Step E35
where the power index Ips in the interface information storage
region Mi is inputted to determine whether the peripheral interface
device 20 is in the no power-saving mode D0. If it is, the control
unit 11 resets the the counter and initializes the input value
C.sub.C. On the contrary, if it is not, go to Step E38 where the
control unit 11 changes the power index Ips to to force the
peripheral interface device 20 to enter the no power-saving mode
D0, and then resets the counting value C.sub.C. On the other hand,
when the input value Flagc indicates the true status in Step E25,
the transmission-state bits Bit0.about.Bitn are inputted and
discriminated to be in enable states or disable states in Step E26.
If the transmission-state bits Bit0.about.Bitn are all determined
to be under the disable states in Step E27, the control unit 11
changes the power mode index Ips, and the interface controller 21
has the peripheral interface device 20 enter the highly
power-saving mode D3 (Step E28, FIG. 3D). Otherwise, if the
transmission-state bits Bit0.about.Bitn are not all under disable
states in Step E27, the power mode index Ips is variously
re-entered by the control unit 11 (Step E39, FIG. 3D). For example,
when there are three of the transmission-state bits Bit0.about.Bitn
remaining in transmission-enable states, the power mode index Ips
is changed to a value indicating the intermediate power-saving mode
D2 of the peripheral interface device 20. Further, the peripheral
interface device 20 enters a primary poser-saving mode D1 in
response to the change of power mode index Ips when there is four
of the transmission-state bits Bit0.about.Bitn remaining in
transmission-enable states. More than four transmission-state bits
Bit0.about.Bitn remaining in transmission-enable states correspond
to another power mode index value and result in the no power-saving
mode D0. After either of the power-saving modes D0, D1, D2 and D3,
the input value C.sub.C is initialized by resetting the associated
counter. It is understood that the input value flagc allows the
user to decide whether the power-saving function is to be entered
or not. After the power-saving functions in response to the
transmission-state bits Bit0.about.Bitn and/or the input value
flagp are determined, the counting value C.sub.C is reset, and Step
E13 (FIG. 3A) where new input values C.sub.P and C.sub.C are
generated and inputted is executed, thereby continuousely
monitoring and optimizing the power consumption of the peripheral
interface device.
[0047] Preferably, the step E18 for discriminating the port
situation indices Ip0.about.Ipm is executed by the sub-steps E181
to E184 as shown in FIG. 3E. First of all, the port situation
indices Ip0.about.Ipm are inputted. Then, the bias-state bit and
the connection-state bit corresponding to each of the port
situation indices Ip0.about.Ipm are determined to be in enable or
disable states. When the bias-state bit and connection-state bit
are both under enable states, which means the bias of the
corresponding expansion port of the peripheral interface device 20
is in a normal state and the connection of the expansion port to
the peripheral device is perfect, the port situation index
associated with the expansion port is discriminated to be under the
enable state. Otherwise, the port situation index is discriminated
to be under the disable state.
[0048] To sum up, the method for enabling the power-saving mode
according to the present invention dynamically detecting the data
transmission states of the peripheral interface device 20 and/or
the utility situations of the expansion ports. Accordingly, the
power status of the system 10 can be dynamically adjusted, thereby
minimizing the power consumption. The power-saving function is
especially important for a portable computer or a cell phone which
relies on battery to work.
[0049] While the invention has been described in terms of what is
presently considered to be the most practical and preferred
embodiments, it is to be understood that the invention needs not be
limited to the disclosed embodiment. On the contrary, it is
intended to cover various modifications and similar arrangements
included within the spirit and scope of the appended claims which
are to be accorded with the broadest interpretation so as to
encompass all such modifications and similar structures.
* * * * *