Drawingboard Ii, A Graphical Input-output Device For A Computer

Abstract

A two-dimensional matrix of semi-conductors is arranged in ordered array as a flat, light emitting and light sensing device activated both electrically and by radiant energy from a penlight to achieve a graphical input and output display by the active or inactive condition of the light emitter with circuitry for control of flow of graphical data into and out of the device for use in conjunction with a digital computer.

Description

BACKGROUND OF THE INVENTION

This invention relates generally to registers and in particular to electrical calculators of the hybred type.

Various devices have been used in the past for placing graphical data into a computer and for display of graphical data generated by a computer.

Cathode ray tube displays have been used with a light pen having a photo sensitive cell directed at the display on the surface of the tube to pick out or place a point in the display.

Other devices use a flat matrix of electrical terminals which are connected to a computer and a metal stylus also connected to the computer which acts as a writing instrument when applied to and traced across the surface of the matrix.

Still other devices use photosensitive materials for receiving information but do not display information back from the same plane of the device after it is entered or processed by the computer. Few of the graphical input-output devices of the prior art provide circuitry which can control the flow of graphical information into and out of the device which is separate and apart from the computer.

SUMMARY OF THE INVENTION

The device of the present invention is a flat graphical input-output device for a computer using light sensors to receive information, with light emitters juxtaposed adjacent corresponding sensors to display information. A penlight, i.e., a "pen" or light emitting writing instrument, is held in the hand of the operator and is used to activate the light sensors. A processor unit is used to control the flow of information into and out of the device for operation with a computer. The processor unit circuitry provides for activating, deactivating and determining the status of each emitter in accordance with either a coded or uncoded signal. The processor unit also is arranged to activate rows, columns and blocks of emitters as desired.

It is, therefore, an object of the present invention to provide a graphical input-output device for a computer.

It is another object of the present invention to provide a graphical input-output device for a computer having individual point control using a coded or uncoded address.

It is still another object of this invention to provide a graphical input-output device for a computer in which the flow of information into and out of the device is separately controlled.

It is another object of this invention to provide a graphical input-output device for a computer in which logical information is associated with the positional information in the graphical display.

It is another object of this invention to provide a graphical input-output device for a computer in which a penlight is used for graphical input.

It is another object of the present invention to provide a graphical input-output device for a computer in which photon output of the penlight is controllable for shading the graphical input and output.

It is another object of the present invention to provide a graphical input-output device for a computer in which the photon output of the graphical display is controllable for information output.

It is still another object of the present invention to provide a graphical input-output device for a computer having apparatus for performing programmed switching routines for special displays, operating commands and manipulation of graphical data.

Other and more particular objects of the present invention will be manifest upon study of the following detailed description when taken together with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of the graphical input-output device of the present invention,

FIG. 2 is a plan and elevational view of a typical emitter-sensor pair,

FIG. 3 is a logic diagram of a typical "point" defined by a light emitter-sensor pair,

FIG. 3A is a more detailed circuit diagram of a typical "point,"

FIG. 4 is a symbol list defining some of the symbols used in the drawings,

FIGS. 5A and 5B is a single line block diagram of the circuitry of the present invention showing the interconnection of the various control units used to operate the device,

FIG. 6 is a circuit diagram showing the connection of primary input register, operations decoder, "B" AND and "C" AND gates, local memory, "F" AND and "G" OR gates, and memory OR gates,

FIG. 7 is a circuit diagram of control registers SR(0) through SR(3) of the drawingboard processor unit,

FIG. 8 is a circuit diagram of control registers SR(4) through SR(6) of drawingboard processor unit,

FIG. 9 is a circuit diagram of the "W" control gates of the drawingboard processor unit,

FIG. 10 is a circuit of the X-input, X-output and X-parts registers as connected to the drawingboard,

FIG. 11 is a circuit diagram of the Y-output register and the XY-, Z'-, and the Z-registers for transmitting the graphical information to the computer,

FIG. 12 is an elevational view of a typical penlight used to place information into and erase information from the graphical device of FIG. 1 along with details of circuitry for connecting it to the device,

FIG. 13 is a circuit diagram of the input character gates register of the drawingboard processor unit,

FIG. 14 is a circuit diagram of an instruction logic device used to measure incremental variations in the graphical display,

FIG. 14A is a circuit diagram of a typical timing chain device used in FIG. 14,

FIG. 14B is a circuit diagram of a device to direct X- and Y-adders to add or subtract one binary digit from the address,

FIG. 15 is a diagram of typical pulse wave forms of the timing device of FIGS. 14, 14A and 14B.

FIG. 16 is a circuit diagram of a corner of the array showing a typical "point" and its interface with peripheral circuitry to the board.

FIG. 17 is a circuit diagram showing the X-decoder in greater detail,

FIG. 18 is a circuit diagram showing the Y-decoder in greater detail,

FIG. 19 is a circuit diagram showing the X-encoder in greater detail,

FIG. 20 is a circuit diagram showing the Y-encoder in greater detail.

DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIG. 1, the graphical input-output device of the present invention comprises, basically, a write and display board 20, i.e., input-output drawingboard 20, which is mounted on an electronic and power supply cabinet 21 having a control panel 22 on the front thereof.

A penlight 23 is electronically connected to board 20 by two or more conductors 86 and 86', 24 and 25 for control of the light output of the penlight as will be described below, and for control of information placed in the board. Board 20 further comprises modular emitter-sensor circuit units or "points" 26 shown typically in FIGS. 2 and 3 arranged in an array 35 (FIG. 1) of horizontal and vertical rows and columns respectively.

Referring to FIG. 2, a modular emitter-sensor pair or "point" 26 is shown in plan and elevation and comprises a compartment in block 27 containing local circuitry, on the top surface of which is mounted a light emitter 28 and a light sensor 29 along with other light sensors further described below. Light emitters 28 may be any light emitting means such as an incandescent or neon glow lamp, however, the present device is arranged to utilize a semi-conductor device such as a light emitting diode common in the art.

Light sensor 29 is, as used in the present embodiment, a semi-conductor device sensitive to electromagnetic radiation.

To protect emitter 28 and sensor 29 from damage, a transparent surface 30 is disposed over the entire surface of array 35.

FIG. 3 illustrates a simplified logic diagram for a typical "point" i.e., emitter-sensor pair circuit 26. Such a "point" 26 comprises an X-sense diode 31 connected on its anode side to X-conductor 32 and a Y-sense diode 33 connected on its anode side to Y-conductor 34. The cathode sides of X- and Y-sense diodes 31 and 32 are connected in common to the output of AND gate 36 and the output of light sensor 29 through pointing circuit 50.

Light emitting diode 28 and one of the inputs to AND gate 36 are connected to the output of memory circuit 37. The other input of AND gate 36 is connected to READ conductor 38 while the two inputs to memory circuit 37 are connected to WRITE conductor 39 and ERASE conductor 40.

With reference to FIG. 3A, a more detailed circuit diagram of a typical point 26 is shown.

The reference numerals of corresponding parts of the circuit of FIG. 3 and 3A are identical.

The identification of each circuit element and its value, where applicable, is listed in Table 1. The number-letter combination under "Type" is the present industrial standard designation for the semi-conductor device used.

Table 2 is a listing of the values for resistors 172 and 173 necessary to change the state of the bi-stable circuit of FIG. 3A. The sensitivity range is generally descriptive. The measured values would range from about 100 foot-candles for an "intense" light to about 0.5 foot-candles for "shadow" light. --------------------------------------------------------------------------- TABLE 1

Ref. No. Type or Value Purpose 160 2N2219 Computer write transistor 161 2N2219 Computer erase transistor 162 1N 2175 Optical write transistor 163 1N2175 Optical erase transistor 164 2N3135 Bi-stable pnp transistor (for memory) 165 2N2219 Bi-stable npn transistor (for memory) 166 2N2219 Driver transistor 29 1N2175 Optical pointing transistor 167 2N4409 Inverting driver transistor 28 MVE100 Light emitting diode 169 1N643 Bias diode 170 1N643 Bias diode 171 1N56AG Isolating diode 33 1N56 AG Y-sense diode 31 1N56 AG X-sense diode 172 10 K Enable sensitivity resistor 173 10 K Disable sensitivity resistor 174 100 ohms Light emitting diode (LED) current limiting resistor 175 10 K Transistor 166 current limiting resistor 176 10 K Bias resistor 177 1 K Transistor 167 current limiting resistor 36 SN7402 NOR gate __________________________________________________________________________ --------------------------------------------------------------------------- Table 2

Value of Resistors Light Level 172 and 173 1 K Intense 10 K Room lamp 100 K Dim 1 Meg Shadow __________________________________________________________________________

From FIG. 3A, WRITE conductor 39 enters circuit 26 through transistor 160 while ERASE conductor 40 enters the circuit through transistor 161 for computer control of the WRITE-ERASE function. The same function can be performed using penlight 23 by activating light sensor 162 to write or light sensor 163 to erase.

Memory is achieved through bi-stable transistors 164 and 165 which "lock in" the "on" or "off" status of the point, i.e., whether or not a current is flowing through light emitting diode 28.

To activate the point, penlight 23 is pointed at light sensing transistor 162 and light sources 88 (FIG. 12) are energized to shine on sensor 162 causing a current to flow through the transistor, applying a voltage to one side of light emitting diode 28 causing a current to flow therethrough.

To deactivate the point, penlight 23 is pointed at light sensing transistor 163 and light sources 88' are energized to shine on sensor 163 reducing its resistance to a value sufficient to lower the voltage across light emitting diode 28 to limit the current therethrough sufficient to turn diode 28 off.

For consistency and understanding of the drawings, FIG. 4 defines the symbols used in the drawings.

OR gate 41 of FIG. 4 is a semi-conductor device having two or more inputs and one output. A signal, i.e., a voltage pulse, on either of the inputs on the left will appear on the output (right) side of the device. AND gate 42 of FIG. 4 is a semi-conductor device having two inputs, both of which must be activated, i.e., have a voltage on the input conductors, for a signal to appear on the output side.

"D" type flip-flop 43 is a bi-stable semi-conductor device having a signal input 44 and a "clock" input 45, a reset input 46 and two logical complimentary out-put conductors 47 and 48.

Activation of clock input 45 will permit a signal on input 44 to pass to output conductors 47 and 48.

Activation of reset input 46 causes all flip-flops 43 to return to a logical zero or "off" position.

Inverting amplifier 49 is a device common in the art for producing the logical compliment of a digital signal.

With respect to the entire system, FIGS. 5A and 5B, shown on two sheets, is a single line block diagram showing the interconnection of the basic electronic switching units which serve to control the flow of information into drawingboard 20 and also to and from the computer (not shown)through drawingboard 20 for the manipulation of the data contained therein.

The computer that is used in conjunction with the device of the present invention can be any digital computer common in the art which can receive, manipulate and transmit information coded in a manner to identify individual bits of information, for example, in the form of voltage pulses on various combinations of conductors or lines leading into and out of the present device.

The blocks in FIGS. 5A and 5Brepresent switching circuits which comprise basically combinations of ANDand ORgates and flip-flop devices with the exception of local memory 106 which may be any type of device common in the art which can temporarily store information. A magnetic core memory common in the art would be one example.

With particular reference to FIG. 5A, there is illustrated the circuits associated with drawingboard 20 used to place information into the board and read information stored in the board.

Basically, drawingboard 20 comprises a 16 by 16 array 35 of "points" 26 having sixteen X-conductors 32 (FIG. 3 and 3A) arranged parallel and equally spaced in a common plane with sixteen Y-conductors 34 arranged parallel and equally spaced normal to X-conductors 32 in said common plane.

A "point" 26 is connected at the intersection of each X- and Y-conductor 32 and 34, respectively.

Array 35, therefore, comprises 256 "points" 26 arranged in 16 horizontal and 16 vertical rows and columns, with each "point" 26 comprising the elements of the circuit of FIG. 3A. FIG. 16 shows array 35 comprising read, write and erase gate registers 154, 155 and 156, respectively, whose outputs are connected to conductors 38, 39 and 40 through read, write and erase point AND gates 157, 158, and 159, respectively.

Thus activation of any of the conductors 38, 39 or 40 will cause data in array 35 to be, respectively, read written, or erased by the computer (not shown) from array 35.

It will be noted that through the use of penlight 23, as previously discussed and shown in FIG. 3A, an individual "point" 26, may be read, written or erased by appropriate photoactivation of transistors 29, 162 or 163, respectively.

To the left and bottom of array 35 (FIG. 5A) are input sides 53Y and 53X. To the right and top of array 35 are the output sides 54Y and 54X.

The input circuitry for the device of the present invention comprises, for the X-sense (X-coordinate), X-input register 56 whose output is connected to X-input side 53X, X-input parts register 57 whose output is connected to the input side of X-input register 56 and whose various inputs are connected to drawingboard processor unit 100 (FIG. 5B).

The output of X-address decoder 58 is connected to the input of X-input parts register 57 while the input side of X-address decoder 58 is connected through XCD gates 115 to drawing board processor unit 100 (FIG. 5B).

In a like manner for the Y-sense (Y-coordinate), the output side of Y-input register 60 is connected to input side 53Y of array 35 while the input side of register 60 is connected to the output side of Y-input parts register 61. The output of Y-address decoder 62 is connected to the input side of Y-input parts register 61 while the inputs of both Y-address decoder 62 (through YDC gates 120) and Y-input parts register 61 are connected to drawingboard proccessor unit 100.

The output circuitry for the device of the present invention comprises, for the X-sense (X-coordinate), X-output register 64 whose input is connected to X-output side 54X, X-output parts register 65 whose input is connected to the output of X-output register 64.

It will be noted that the output of X-output register 64 is also connected to the input of X-address encoder 66 whose output is connected both to multiple input OR gate XOOR 150 and XEC gates register 81 (FIG. 17).

In a like manner, for the Y-sense (Y-coordinate), the input side of Y-output register 68 is connected to Y-output side 54Y, while its output side is connected to the input side of Y-output parts register 69.

It will also be noted that the output of Y-output register 68 is connected to the input of Y-address encoder 70 whose output is connected both to multiple input OR gate YOOR 151 and YEC gates register 124 (FIG. 18).

Both X- and Y-output parts registers 65 and 69 are connected to drawingboard output register 73 whose output is connected to the computer (not shown).

All registers, it will be noted, are connected to drawingboard processor unit 100.

DRAWINGBOARD PROCESSOR UNIT

FIG. 5B shows the interconnection of the various block circuits contained in the drawingboard processor unit 100.

Basically, drawing board processor unit 100 comprises a primary input register 101, whose output is variously connected to operations decoder 102, "C" AND gates register 103, "B" ANDgates register 104 and instruction logic circuit 152.

Operations decoder 102 is variously connected to local memory 106, "F" AND gates register 107, "address code" status register SR(0) 108, "input part" status register SR(1) 109, "output parts" status register SR(2)110, "read status" status register SR(3)111, "labels" status register SR(4) 112, "location storage"status register SR(5)113, and "memory buffer"status register SR(6) 114 and instruction logic circuit 152.

Drawingboard processor unit 100 further comprises, input character gates register 116, "W" gates register 117, "G" OR gates register 118, and memory OR gates register MOR 119.

To describe the device of the present invention in detail, certain conventions will be used to organize the material. The letters "A"through "Z" are used to identify the lines or circuits interconnecting the various circuit units or blocks. For example, line A(1) designates line "1" of circuit "A," X(0- 7)designates lines "0" (zero)through "7" of circuit "X."

Certain abbreviations may be used which will be self evident such as "XIP" for X-inputs parts register; "YOP" for Y-output parts register and "SR" for status register.

Since certain commands are required for various control functions, these are designated by the command number contained in a circle when shown on the drawings and preceded by an asterisk "*" when discussed in the specification. For example, a command identified by "03" in a circle on a drawing is identified as "*03" in the specification.

The arrows which are incorporated into the circuit lines represent the flow of information or data through drawingboard 20 and processor unit 100 in accordance with the direction of the arrow.

As for detailed discussion of the circuit units of the present invention, it is apparent to one skilled in the art that the use of AND gates, OR gates and flip-flop devices in switching circuits is common in the art and the function of each individual circuit element can be followed by such person without further detailed explanation.

To describe in detail the individual circuit units of drawingboard processor unit 100, reference is made to FIG. 6 and beginning in particular to primary input register 101.

Primary input register 101 comprises a plurality, sixteen in the present embodiment, of flip-flop circuit units 121 having outputs A(0) through A(15). The input signal enters register 101 in a manner such that the first five "bits," A(0) through A(4) of information are an encoded "command" signal; the next three "bits," A(5), A(6), and A(7) are an encoded instructional signal also identified as lines I(0), I(1) and I(2), respectively; and the remaining eight "bits" are an encoded X-Y address signal for a particular "point" 26, four "bits"for the X-address and four "bits" for the Y-address.

Operations decoder 102 comprises a set of input OR gates 122, a decoder unit 105 common in the art which converts the "on" or "off"status of either lines A(0-4) or E(0-4) to a pulse or signal on any one of 00 to 37 (octal) outputs on 32 lines (decimal).

Command lines *01 through *37 are connected to the registers for control of array 35 The detailed operation of each command is described supra.

"B" AND gates register 104 is used to bypass coded adderess information around local memory 106 while "C" AND gates register 103 is used to place coded address information into local memory 106.

The output of lines A(7) (also identified as line I(2)) and A'(7) of the instructional coded section of primary input register 101 are used to gate the flow of information through "C" and "B"gates registers 103 and 104 respectively. The signal on line A'(7) is the logical compliment of the signal on line A(7).

Local memory 106 can be any memory unit common in the art for storing "bits" of information such as a magnetic core matrix and the like common in the art.

Local memory OR gates register MOR 119 comprises eight OR gates which control the flow of information from memory 106, instruction logic circuit 152 and "B" AND gates register 104 into lines X'(0-3) and Y'(0-3).

"F" AND gates register 107 comprises all AND gates 134 and "G" OR gates register 118 comprising all OR gates 135 are used to control the flow of information into "memory buffer" status register SR(6) 114 (FIG. 5B).

With reference to FIGS. 7 and 8, there is shown the detailed circuit diagram for status registers SR(0) through SR(6) reference numerals 108 through 114, respectively.

Basically, each status register comprises a column of bi-stable flip-flop devices 125 and a column of AND gates 126.

Typically, two command lines 127 and 128 are connected to flip-flop devices 125. Line 127 is connected in common to the "clock" input terminals of each flip-flop device 125 for the purpose of transferring the status of the "signal" input lines into the register, and the other command line 128 is connected in common to the "reset" input of flip-flop devices 125 to reset all flip-flop devices to a logical zero or "off" status.

It will be noted that AND gates 126 are used to gate information out of the status registers upon appropriate activation of lines RSW(0-7) of status register SR(3) 111.

Status registers SR(0-6), reference numerals 108 through 114, are identified as shown in Table 3 as follows: --------------------------------------------------------------------------- TABLE 3

Ref. Abbrev. Title Function No. __________________________________________________________________________ 108 SR(0) Address Codes Stores address codes 109 SR(1) Input parts Stores input parts codes 110 110 SR(2) Output Parts Stores output parts codes 111 SR(3) Read Status Stores "read Status" codes 112 SR(4) Labels Stores "labels" codes 113 SR(5) Location Storage Stores "location Storage" codes 114 SR(6) Memory Buffer Stores "memory buffer" codes __________________________________________________________________________

With reference to FIG. 13, there is shown the detailed circuit diagram for character gates register 116 which comprises 32 AND gates 130.

Register 116 converts the coded address of a typical "point"26 on lines X'(0-3) and Y'(0-3) to activation of lines X(0-15) and Y(0-15) by appropriate activation of lines XIC(0-1), and YIC(0-1). For example, concurrent activation of lines Y'(2) and XIC(1) will cause line X(14) to be activated.

FIG. 9 illustrates a detailed circuit diagram of "W" gates register 117 which comprises eight lower OR gates 132 and eight upper OR gates 133. The lower OR gates 132 have input and output lines as tabulated in Table 4. The upper OR gates 133 have input and output lines as tabulated in Table 5.

TABLE 4

Output Input Lines Lines L(0), M(0), O(0), P(0), Q(0), R(0) W(0) L(1), M(1), N(1), O(1), P(1), Q(1), R(1) W(1) L(2), M(2), N(2), O(2), P(2), Q(2), R(2) W(2) L(3), M(3), N(3), O(3), P(3), Q(3), R(3) W(3) L(4), M(4), N(4), O(4), P(4), Q(4), R(4) W(4) L(5), M(5), N(5), O(5), P(5), Q(5), R(5) W(5) L(6), M(6), N(6), O(6), P(6), Q(6), R(6) W(6) L(7), M(7), N(7), O(7), P(7), Q(7), R(7) W(7)

TABLE 5

Output input Lines Lines Y(8), Y(0), X(8), X(0), R(8), S(0) W(8) Y(9), Y(1), X(9), X(1), R(9), S(1) W(9) Y(10), Y(2), X(10), X(2), R(10), S(2) W(10) Y(11), Y(3), X(11), X(3), R(11), S(3) W(11) Y(12), Y(4), X(12), X(4), R(12), S(4) W(12) Y(13), Y(5), X(13), X(5), R(13), S(5) W(13) Y(14), Y(6), X(14), X(6), R(14), S(6) W(14) Y(15), Y(7), X(15), X(7), R(15), S(7) W(15)

DRAWINGBOARD

With reference now to FIGS. 10 and 11, FIG. 10 is a logic diagram of the input and output register circuits for drawingboard 20. The input and output register circuits in the Y-direction are identical to those in the X-direction and, therefore, are not repeated in the drawing. Discussion of the X-input and output circuitry applies as well to the Y-input and output circuitry. FIG. 11 is a circuit diagram of drawing board output register 73 as well as a circuit diagram of Y-output register 68 and Y-output parts register 69.

Referring to FIG. 10, X-input parts gate register 57 comprises a set of sixteen X-parts ANDgates 75 and a set of sixteen X-parts OR gates 76.

One side of the input to AND gates 75 is connected consecutively in groups of four, to lines X'(O-3). The other side of the input to AND gates 75 is connected in common, in groups of four, to lines XIP(0-3). It can be seen, using this arrangement, that by selective activation of lines X'(0-3) and XIP(0-3), only one line or a combination of lines X(0-15) can be activated. Thus, combined with the Y-direction, one point or combination of points will be activated.

Input register 56 comprises sixteen bi-stable flip-flop devices 77 which act to control the flow of the information on the output lines 78 of input parts register 57 into array 35.

Command lines *01 and *02 for the X- and Y-coordinates are used to control the flow of such information. Command lines *10 and *11 (FIG. 5A)are used to reset X-input register 56 and Y-input register 60, respectively, to a logical zero of "off"status.

X-output register 64, similar to X-input register 56 comprises sixteen bi-stable flip-flop devices 79 which act to control the flow of information out of array 35.

Line ROR to X- and Y-output registers 64 and 68 from OR gate 145 (FIG. 12) is used to control the flow of output information. Command lines *13 and *14 (FIG. 5A) are used to reset X-output register 64 and Y-output register 68, respectively, to a logical zero or "off" status.

X-output parts gate register 65 comprises all AND gates 80. It will be noted that one side of the input to AND gates 80 is connected in common, in groups of four, to lines XOP(0-3). Thus by appropriate activation of lines XOP(0-3), information is gated out of X-output register 64 into drawingboard output register 73 (FIG. 11).

Referring to FIG. 11, drawingboard output register 73 comprises XY OR gates register 82, Z-OR gates register 83 and Z-output register 84 which is connected to Y-output parts gate register 69 and X-output parts gate register 65 at the input side of XY OR gate register 82.

Z-output register 84 comprises sixteen bi-stable flip-flop devices 85 used to transfer information from its input side to the computer (not shown). Command line *06 is used to control the flow of the information to the computer while command line *15 is used to reset all the bits of output register 84 to a logical zero or "off" state.

With reference to FIG. 5A and in particular to X-address decoder 58, Y-address decoder 62, X-address encoder 66 and Y-address encoder 70, the circuitry for these devices is common in the art and comprises AND gates YDC 120, XDC 115, YEC 124 and XEC 81 and inverting amplifiers such that the "on" and "off" status combination of four input lines into address decoders 58 and 62 causes activation of only one of 16 output lines of the decoder, and for encoder 66 or 70, activation on one of 16 input lines causes a particular combination of "on-off" states of four output lines of the encoder.

Typically in FIG. 19 is shown X-address decoder 58 connected to XDC gates register 115. XDC gates register 115 comprises four AND gates 59 whose outputs are connected to X-address decoder 58.

One input side of AND gates 59 is connected individually to line X'(0-3) while the other side is connected in common to line XDC from status register SR(0) 108.

In a similar manner, FIG. 20 shows Y-address decoder 62 connected to YDC gates register 120. YDC gates register 120 also comprises four ANDgates 63 whose outputs are connected to Y-address decoder 62.

One input side of ANDgates 63 is connected individually to lines Y'(0-3) while the other side is connected in common to line YDC from status register SR(0)108.

Typically, in FIG. 17 is shown X-address encoder 66 with output connected to multiple input OR gate XOOR 150 and AND gates register XEC 81 comprising all AND gates 67. It will be noted that the four outputs of X-address encoder 66 are connected individually to one input side of AND gates 67 while the other side is connected in common to line XEC coming from status register SR(0) 108.

In a similar manner, with reference to FIG. 18, the output of Y-address encoder 70 is connected to multiple input OR gate YOOR 151 and individually to one input side of AND gates 74 of AND gates register YEC 124. The other side of AND gates 74 is, similar to that for register XEC81, connected in common to line YEC coming from status register SR(0) 108.

With reference to FIG. 12, therein is shown an elevational cross section of a typical penlight 23 and its associated circuitry.

Penlight 23 comprises a writing end 87, and erase end 87' each end having transparent light guides 89 and 89' to focus light emitted by light source 88 and 88', respectively, onto array 35.

Light sources 88 and 88' are supported on sliding supports 90 and 90', which are biased toward ends 87 and 87' by use of helical springs 91 and 91', respectively.

Attached to each support 90 and 90' are a set of electrical contacts 92 and 92' which are used to connect light sources 88 and 88' to a source of electrical power when either end 87 or 87' is pressed against surface 30 of drawingboard 20.

Additional electrical contacts 93 and 93' are provided permitting connection of penlight 23 to erase-write circuit 94 and instruction transmit circuit 95 through conductors 24 and 25.

An inking cartridge or writing instrument 96 is attached to support 90 at write end 87 while an eraser 97 is attached to support 90' at erase end 87'.

All parts of the penlight are enclosed in a housing 98 of a dimension suitable for an operator to use as a writing or erasing instrument.

Erase-write circuit 94 comprises two "on-off" switches 138 and 139 to connect penlight 23 to OR gates 140 and 141 which allows penlight 23 to control drawingboard array 35 using erase array line (EOR) 129 and write array line (WOR) 131. Command lines *05 and *04 allow the computer (not shown) to instruct array 35 to erase and write through OR gates 140 and 141, thus permitting both man and machine to alter the information displayed in array 35.

Circuit 95 comprises "point" OR gate (POR) 142 whose input side is connected to lines 24 and 25 from penlight switches 93 and 93', respectively. "Point-one-shot" (POS) flip-flop 147 whose input is connected to the output side of OR gate POR 142 has its output side connected to "READ"OR gate (ROR) 145 and interrupt OR gate (IOR)144. The input side of (ROR) gate 145 is also connected to command line *03 through inverting amplifier 137 and line 153 from circuit 152.

Circuit 95 also comprises OR gate 143 having its input side connected to Y-output OR gate (YOOR) 151 and X(output OR gate (XOOR) 150, XY-point AND gate (XYP) 146 whose one input side is connected to the output side of OR gate 143, whose other input side is connected to the output of (POR) 142, and whose output is connected to interrupt OR gate 144 (IOR) whose input side is connected to the output of (POS) flip-flop 147, whose other input side is connected to XY-point AND gate (XYP) 146 has its output connected to mode switch 149.

Inverting amplifier 137 is provided at the input of command line *03 while another inverting amplifier 148 is provided for the output of (IOR) gate 144 to produce the logical compliment of the signals entering the amplifier.

It will be noted that a switch 149 is provided at the input side of amplifier 148 to permit the operation of array 35 by use of penlight 23 without the use of a computer (not shown).

It can be seen that a signal will occur on lines 24 and 25 whenever either write end 96 or erase end 97 is pressed against surface 30 of drawingboard 20 activating, respectively, either switch 93 or switch 93'. This signal will then pass through "point" OR gate (POR) 142 to activate the "point-one-shot" (POS) flip-flop 147 and one side of XY-point AND gate (XYP) 146.

A signal will appear at OR gate 143 if any X- or Y-bit, i.e., flip-flop, is in the logical "one" state in X-output register 64 or Y-output register 68, and will pass on to XY-point AND gate (XYP) 146.

Both AND gate 146 and (POS) flip-flop 147, connected as noted above to interrupt OR gate (IOR) 144, allows an interrupt signal to be sent to inverting amplifier 148 provided switch 149 is in the "line" position.

The connection scheme of circuit 95 provides interrupt signals on line I(1) for any one of the following conditions:

a. When penlight 23 is used to point at a single point 26 being held fixed against surface 30, or

b. When penlight 23 is used to draw a line by pressing end 87 against surface 30 and moving it along the surface thereof to send a series of "point" address signals to the computer (not shown).

By placing switch 149 in the "local" position, a display of graphic material can be written in or erased from array 35 without informing the computer (not shown) that an action has been taken.

Whenever command line *03 is activated by the computer (not shown)to read data in the drawingboard, the signal will pass through inverting amplifier 137 to read array OR gate (ROR) 145. In a similar manner, any pointing action by penlight 23 resulting in the triggering of monostable flip-flop 147, will also send a signal through read array OR gate (ROR)145 to transfer the status of points 26 that are currently being selected from array 35 to X-output and Y-output registers 64 and 68, respectively. This is achieved by the fact that the output side of gate (ROR) 145 is connected in common to the clock input terminals of the flip-flops forming X- and Y-output register 64 and 68 respectively.

It will be noted in FIG. 12 that a potentiometer 52 is provided in the circuit with power source 99 in order to control the brightness or intensity of the radiant energy flux from typical light source 88. Penlight 23 can thus be used to input "shading" information into array 35 using appropriate brightness or intensity measuring circuits common in the art such as photosensitive transistors and analog to digital voltage converters, whose digital output can be stored in a memory common in the art.

Conversely, the brightness or intensity of light output from light emitting diodes 28 can be regulated by the use of any current controlling means such as a field effect transistor in place of resistor 174 (FIG. 3A). In particular, the bias voltage on the control terminal (gate or base) would determine the amount of current that is allowed to pass through light emitting diode 28. The control terminals are then connected in common to all points 26 of array 35 and the voltage on the conductor to the common connection is determined by a video amplifier, digital to analog converter or other means common in the art.

Whereas the present embodiment illustrated in FIG. 3A provides for two discrete states ("on" and "off") of light emitting diode 28, provision can be made, as described above, for a third dimension of graphical input and output in the form of "point" 26 brightness or intensity.

FIG. 16 is a circuit diagram of one corner of drawingboard 20 showing sides 53X, 53Y, 54X, and 54Y which act as an interface between array 35 and X- and Y-input registers 56 and 60 and X- and Y-output registers 64 and 68.

From FIGS. 5Aand 10, it will be noted that lines *03, *16, (WOR) 131 and (EOR)129 are shown collectively entering array 35 in the upper left hand corner. These lines are shown individually in FIG. 16, which is a section of the lower left hand corner of array 35 at point X(0)-Y(0), running along input sides 53X and 53Y.

READ command line *03, WRITE line 131 from WOR 141 and ERASE line 129 from EOR 140 are each connected respectively to AND gates RX(0) and RY(0), WX(0)and WY(0), and EX(0)and EY(0), for point 26 corresponding to an address of X(0)-Y(0). Similar AND gates are provided in the X- and Y-direction for other "points" 26 coordinates.

The input of ANDgates RX(0) and RY(0) are respectively connected to the output of X'(0) and Y'(0) flip-flops of X- and Y-input registers 56 and 60.

It will be noted that the outputs of AND gates RX(0), WX(0), RY(0) and WY(0) are, typically, connected to input inverting amplifiers 180, 181, 182, and 183, respectively, while the output of AND gates EX(0) and EY(0) are connected, respectively, to OR gates EOX(0) and EOY(0). The other input to OR gates EOX(0) and EOY(0)is connected in common to command line *16 whose function is to erase all information from array 35.

Typically, read point AND gate RP(0,0) 157, write point AND gate WP(0,0) 158 and erase point AND gate EP(0,0) 159 have one of their inputs connected, respectively, to lines 185, 186 and 187 originally coming from AND gates RX(0), WX(0) and EX(0), while the other input is connected, respectively, to lines 188, 189 and 190 originally comming from AND gates RY(0), WY(0) and EY(0).

The output of AND gates RP(0,0), WP(0,0)and EP(0,0) is connected, respectively, to READ line 38, WRITE line 39 and ERASE line 40 in turn connected to "point" circuit 26 which is the same circuit as shown in FIG. 3 and 3A.

Thus, for information to pass through any of AND gates RP(0,0), WP(0,0) or EP(0,0), any of lines 185, 186 or 187 in the X-direction must be activated concurrently with any of lines 188, 189 or 190 in the Y-direction.

Output information in the X-direction is conveyed by line 32, which is connected to all other "points" 26 with an X-coordinate of X(0), up to the X'(0)flip-flop of X-output register 64 through X-output inverting amplifier 192.

Output information in the Y-direction is conveyed by line 34, which is connected to all other "points" 26 with a Y-coordinate of Y(0), over to the Y'(0) flip-flop to Y-output register 68 through Y-output inverting amplifier 193.

OPERATION

Penlight Writing

To operate the graphical input-output device of the present invention using penlight 23 for information input, the operator holds penlight 23 (FIG. 12) with write end 87 against surface 30 over array 35 of drawingboard 20 over a particular "point" 26 and presses down with the tip of pen 96 until the contacts of switch 92 are closed causing a current from power source 99 to activate light source 88 in turn resulting in radiant energy or light to be guided and focused by light guide 89 and shine on light sensitive transistors 162, 163, or 29 (FIG. 3A).

Activation of write transistor 162 by the electromagnetic or radiant energy from penlight 23 as indicated by the curved arrow pointing toward transistor 162, will cause transistor 165 to become activated resulting in a current flowing through resistor 174, transistor 164 and light emitting diode 28 causing diode 28 to emit light as indicated by the curved arrow pointing away from diode 28, under which condition the "point" is considered as having been "written."

Current will continue to flow through light emitting diode 28 once the light from penlight 23 has activated transistor 162 due to the latching ability of transistor pair 164, 165.

Alternatively, a second or indirect method of writing is also available. If switch 149 of circuit 95 (FIG. 12) is in the "local" position and switch 139 of circuit 94 is in the "on" position, then activation of penlight contacts 93 will cause a current to flow in conductors 25 to activate OR gate WOR 141 whose output is the "write" command line 131 to array 35. The purpose of this path is to provide means for checking the operation of array 35.

Penlight Erasing

In a similar manner, electromagnetic or radiant energy activation of erase transistor 163 causes transistor 165 to become deactivated which in turn deactivates transistor 164, thereby reducing the current through resistor 174 and light emitting diode 28 to turn diode 28 "off" at which time the point is considered as having been "erased."

Similarly a second erase path also provides further means for checking the operation of array 35.

Penlight Pointing

Activation of transistor 29 (FIG. 3A) by electromagnetic or radiant energy will cause a current to flow through diodes 31 and 33, resulting in a change of voltage and flow of current on X-sense and Y-sense conductors 32 and 34.

The closing of penlight contacts 93 will cause a signal to be impressed on WRITE conductor 25 which will pass through pointing OR gate POR 142 to activate pointing one-shot flip-flop POS 147 which, in turn, sends a signal through read output register OR gate (ROR) 145 which then transfers the address of the particular point being pointed at into X- and Y-output registers 64 and 68.

If switch 139 of circuit 94 (FIG. 12) is in the "off" position and switch 149 of circuit 95 is in the "line" position (FIG. 12), then an interrupt signal is sent to the computer through interrupt OR gate IOR 144, mode switch 149 and inverting amplifier 149 along line I(1).

In response to the interrupt signal, the computer (not shown) may then receiver the X- and Y-address information from X- and Y-output registers 64 and 68 through drawingboard output register 73.

The computer can then return the address signal back to array 35 through primary input register 101 along with any desired command such as read (*03), write (*04) or erase (*05).

For example, referring to FIG. 16, if the operator wishes to "read" a "point" 26 on array 35, he uses penlight 23, as described above, to point at the particular "point." The X- and Y-address of the point is sent to the computer as described above and returned to drawingboard 20 through drawingboard processor unit 100 along with a "Read Drawingboard" command signal *03.

The X- and Y-address signal is decoded as will be described and appears at one input of "read input" AND gates RX(0-15) and RY(0-15) from X- and Y-input registers 56 and 60.

Since the other input side of AND gates RX(0-15)and RY(0-15) are connected in common to READcommand line *03, activation of line *03 gates the status of X- and Y-input registers 56 and 60 into array 35. The coincidence of signals on lines 185 in the X-direction and 188 in the Y-direction will be detected through the matrix of AND gates RP(0,0) through RP(15, 15) to activate typical READconductor 38 for each individual point 26 circuit.

In a similar manner, if the operator wishes to write a "point" 26 on array 35, he uses penlight 23, as described above, pointing with write end 87 with switch 139 of circuit 94 in the "off"position.

The X- and Y-address of the point is sent to the computer as described above and returned to drawingboard 20 through drawingboard processor unit 100 along with a "Write Drawingboard" command signal *04.

The X- and Y-address signal is decoded as will be described and appears at one input side of AND gates WX(0-15) and WY(0-15)from X- and Y-input registers 56 and 60.

It will be noted from FIG. 12 that WRITE command line *04 is shown in circuit 94 connected to one input of OR gate WOR141 whose output is connected to line 131 which in turn is connected to the other input side of ANDgates WX(0-15) and WY(0-15) (FIG. 16). Thus activation of line 131 by line *04 gates the status of X- and Y-input registers 56 and 60 into array 35. The coincidence of signals on lines 186 in the X-direction and 189 in the Y-direction will be detected through the matrix of AND gates WP(0,0) through WP(15,15) to activate typical WRITE conductor 39 for each individual "point" 26 circuit.

Also, in a similar manner, if the operator wishes to erase a "point"26 in array 35, he uses penlight 23, as described above, pointing with erase end 87' with switch 138 of circuit 94 in the "off" position.

The X- and Y-address of the point is sent to the computer as described above and returned to drawingboard 20 through drawingboard processor unit 100 along with an "Erase Drawingboard"command signal *05.

The X- and Y-address signal is decoded and appears at one input side of AND gates EX(0-15) and EY(0-15) from X- and Y-input registers 56 and 60.

It will be noted from FIG. 12 that ERASE command line *05 is shown in circuit 94 connected to one input side of ORgate EOR 140 whose output is connected to line 129 which in turn is connected to the other input side of AND gates EX(0-15) and EY(0-15) (FIG. 16). Thus activation of line 129 by line *05 gates the status of X- and Y-input registers 56 and 60 into array 35. The coincidence of signals on line 187 in the X-direction and 190 in the Y-direction will be detected through the matrix of AND gates EP(0,0) through EP(15,15) to activate ERASE conductor 40 for each individual "point" 26 circuit.

It can be seen that those "points" 26 pointed at will appear as addresses returned from the computer which are to be erased, read or written.

It can also be seen that with appropriate programming of the computer, either only those "points" pointed at can be erased or specific "points" having a mathematical relationship to the point being pointed at can be erased, read or written.

In order to erase all information from array 35 "Erase Array" command line *16 (FIG. 16) is connected in common to the other input side of OR gates EOX(0-15)and EOY(0-15) 184. Activation of line *16 activates all lines 187 and 190 in turn activating all ERASE lines 40 by virtue of the coincidence of activation of the two inputs to the entire matrix of AND gates EP(0,0) through EP(15,15).

Computer Input to Drawingboard

Output information from the computer (not shown) enters the input-output devices of the present invention first through primary input register 101 (FIGS. 5 and 6) of drawingboard processor unit 100 as previously described.

The address signal, in the form of a pattern or combination of voltages on eight lines, enters the upper half of register 101, passes through either "B" AND gates register 104 to memory ORgates register MOR119 (called "Direct Addressing")or "C" AND gates register 103 through local memory 106 (called "Indirect Addressing")to memory OR gates register MOR119. From MOR 119 the signal passes to X- and Y-input parts register 57 and 61, respectively, and X- and Y-address decoders 58 and 62, respectively, also to status registers SR(0-4), reference numerals 108 through 112 and to character gates 116.

The signal for activating a particular "point" 26 may then follow any one of three routes from the memory OR gates MOR 119 to the X- and Y-input parts registers 57 and 61.

By the first route, status register SR(1) 109 provides an X- and Y-input signal on lines XIP(0-3) and YIP(0-3) to go directly to X- and Y-parts registers 57 and 61, respectively, which allows the coded address to activate any of the sixteen X- and any of sixteen Y-input lines to array 35 in groups of four.

By the second route, status register SR(0) 108 allows an X- and Y-input decoded signal from X-address decoder 58 and Y-address decoder 62 to arrive at the X- and Y-input parts register OR gates 76 and 72, respectively, activating only one of each of the 16 X- and sixteen Y-input lines to array 35 by activating lines XDC and/or YDC.

By the third route, status register SR(0) 108 allows X- and Y-input character lines XIC(0-1) and YIC(0-1) from character gates register 116 to activate any of the sixteen X- and sixteen Y-input lines X(0-15) and Y(0-15) to X- and Y-input parts OR gates registers 76 and 72 respectively in groups of eight.

Drawingboard Output to Computer

Information contained in drawingboard 20 according to the "on" or "off" status of light emitting diodes 28 is transmitted to the computer by the use of commands described supra.

The flow of "point" 26 address information can also follow several routes:

It can flow from X- and Y-output register 64 and 68, to X- and Y-address encoders 66 and 70, respectively, where it is encoded into a pattern or combination of voltages on eight lines O(8-15) in accordance with signals on lines XEC and YEC from status register SR(0) 108.

It can flow from X- and Y-output registers 64 and 68, to X- and Y-output parts registers 65 and 69, respectively, where it is encoded in accordance with signals on lines XOP(0-3) and YOP(0-3) from status register SR(2)110 and thence to drawingboard output register 73.

Information can flow from local memory 106 through "F" AND gates register 107, through "G" OR gates register 118, through status register SR(6) 114 to "W" OR gates register 117 to Z-OR gates register 83 of drawingboard output register 73 where it is collected and sent to the computer.

Command System

To further describe the use and operation of the graphical input-output device of the present invention, primary control of the flow of information is determined by signals on command lines *01 through *37. The functions of the commands are as follows:

*00 "No Operation:" All command lines are inactive, i.e., "off."

*01 "Jam X-input Register:" The status of the X-address part of primary input register 101 is transferred to X-input register 56.

The X-address information passes through "B" AND gates register 104 if A(7) (also identified as I(2)) is inactivated or "C" AND gates register to local memory 106 if A(7) (also identified as I(2)) is activated. The information can then follow three paths as previously described under "Computer Input To Drawingboard."

a. if lines XIP(0-3) of status register SR(1) 109 are activated, then the address information is decoded by X-input parts AND gate register 75 of X-parts register 57.

b. If line XDC in status register SR(0) 108, is activated, then the address information is decoded by X-address decoder 58.

c. If lines XIC(0-1) from status register SR(0) to input character gates register 116 are activated, then the address information is decoded by input character gates register 116.

*02 "Jam Y-input Register:" The status of the Y-address part of primary input register 101 is transferred to Y-input register 60.

In a manner similar to command *01, Y-address information passes through "B" AND gates register 104 if A(7) (also identified as I(2)) is inactivated or "C" AND gates register 103 to local memory 106 if A(7) (also identified as I(2)) is activated. The information then follows one of three paths previously described under "Computer Input to Drawingboard. "

a. If lines YIP(0-3) of status register SR(1)109 are activated, then the address information is decoded by Y-parts AND gates register 71 of Y-parts register 61.

b. If line YDC in status register SR(0) 108 is activated, then the address information is decoded by Y-address decoder 62.

c. If lines YIC(0-1) from status register SR(0) to input character gates register 116 are activated, then the address information is modified by input character gates register 116.

*03 "Read Drawingboard:" Selects and interrogates points 26 on array 35 as to whether emitters 28 associated with a "point" 26 are activated or not activated.

*04 "Write Drawingboard:" Selects and activates those points on the array 35 addressed by the intersection of the bit patterns in the X- and Y-input registers 56 and 60.

*05 "Erase Drawingboard:" Selects and deactivates those points on array 35 defined by the intersection of the bit patterns in the X- and Y-input registers 56 and 60.

*06 "Jam Output Register:" Transfers the status of X- and Y-output registers 64 and 68 to Z-output register 84 of drawingboard output register 73 depending upon the activated or inactivated condition of status registers SR(0) through SR(6), reference numerals 108 through 114.

a. If lines XEC and YEC of status register SR(0) 108 are activated, and SR(2) 110 is not activated, then the X- and Y- addresses are encoded by X- and Y-address encoders 66 and 70 and transferred into Z-output register 84.

b. If lines XOP(0-3) and YOP(0-3) of status register SR(2) 110 are activated, and SR(0) 108 is not activated, then X- and Y-output parts registers 65 and 69 will encode the X- and Y-addresses, respectively.

*07 "Read Memory:" Transfers the contents of the location selected by the address input lines C(0-7) to the data output lines E(0-15) of local memory 106.

*10 "Clear X-input Register:" Resets all flip-flop devices in X-input register 56 to the "off" or logical zero status.

*11 "Clear Y-input Register:" Resets all flip-flop devices in Y-input register 60 to the "off" or logical zero status.

*12 "Clear input Register:" Resets primary input register 101 to the "off" or logical zero status.

*13 "Clear X-output Register:" Resets all flip-flop devices in the X-output register 64 to the "off" or logical zero status.

*14 "Clear Y-output Register:" Resets all flip-flop devices in Y-output register 68 to the "off" or logical zero status.

*15 "Clear Output Register:" Resets all flip-flop devices in the Z-output register 84 to the "off"or logical zero status.

*16 "Clear Array:" Sets all points 26 in array 35 to the "off," inactivated or logical zero status.

*17 "Clear Array, X-, Y-, S-, I- and O-registers:" Sends pulses through all OR gates 123 of operations decoder 102 (FIG. 6) reseting all connected registers to the "off" or logical zero status.

*20 "Jam Status Register SR(0):" Transfers status of lines X'(0-3) and Y'(0-3) to lines YIC(0-1), XIC(0-1), XEC, YEC, XDC and YDC of status register SR(0) 108.

*21 "jam Status Register SR(1):" Transfers status of lines X'(0-3) and Y'(0-3) to lines XIP(0-3) and YIP(0-3).

*22 "jam Status Register SR(2):" Transfers status of lines X'(0-3) and Y'(0-3) to lines XOP(0-3) and YOP(0-3).

*23 "jam Status Register SR(3):" Transfers status of lines X'(0-3) and Y'(0-3) to lines RSW(0-7).

*24 "jam Status Register SR(4):" Transfers status of lines X'(0-3) and Y'(0-3) to the input side of AND gates 126 of status register SR(4)112 to allow a "lavel" to be associated with an X- and Y-address (FIG. 8).

*25 "jam Status Register SR(5):" Transfers the status of lines O(8-15) to the input side of ANDgates 126 of Status Register SR(5) 113, assuming lines XEC and YEC of SR(0) 108 are in the activated status. The leading edge of the pulse on these command lines transfers the information into binary storage elements 125 while the trailing edge locks the information into the register for later analysis in accordance with the usual method of using the "D" type flip-flop device.

*26 "Jam Status Register SR(6):" Transfers the status of lines G(0-15) from "G" OR gates register 118 by pulsing the clock input terminals of flip-flop devices 125 into SR(6).

*27 "write Memory:" Transfers the status of data lines W(0-15) into the location in memory 106 represented by the status of address lines C(0-7) by energizing write amplifiers (not shown) or equivalent circuits common in the art, located in local memory 106.

*30 "Clear Status Register SR(0):" Resets all flip-flop devices in SR(0) 108 to the "off" or logical zero status.

*31 "Clear Status Register SR(1):" Resets all flip-flop devices in SR(1) 109 to the "off" or logical zero status.

*32 "Clear Status Register SR(2):" Resets all flip- flop devices in SR(2) 110 to the logical zero or "off" status.

*33 "Clear Status Register SR(3):" Resets all flip-flop devices in SR(3) 111 to the "off"or logical zero status.

*34 "Clear Status Register SR(4):" Resets all flip-flop devices SR(4) 112 to the "off" or logical zero status.

*35 "Clear Status Register SR(5):" Resets all flip-flop devices in SR(5) 113 to the "off" or logical zero status.

*36 "Clear Status Register SR(6):" Resets all flip-flop devices in SR(6) 114 to the "off" or logical zero status.

*37 "Clear Memory:" Resets all parts of memory 106 to the reset or logical zero status.

Increment Apparatus and Operation

Apparatus

For a graphical display of information in the form of a line, i.e., a locus of points defining a line, it is desirable to be able to sequentially read the activated points into the computer (not shown).

FIG. 14 is a circuit diagram of "I" logic circuit 152 useful for such a purpose.

Circuit 152 comprises a base address register 200 having eight input AND gates 201 with input lines A(8-15)connected to the input of AND gates 201, an X-adder 203 and Y-adder 204 having their input connected to the output of base address register 200, X-adder input corresponding to lines A(8-11) and Y-adder input corresponding to lines A(12-15), and relative address register 205 comprising eight flip-flop devices 206 whose inputs are connected to X- and Y-adders 203 and 204 and whose output is connected to memory OR gates 119 (FIG. 6) by lines H(8-15) to address array 35.

X- and Y-adders 203 and 204 are circuits which are common in the art which take a number input and either adds or subtracts "one" from the number and gives the sum or difference as its output.

Circuit 152 also comprises status register SR(7)210 having at its input side eight AND gates 211 whose output side is connected to eight corresponding flip-flops 212 whose output is connected to eight corresponding AND gates 213 constituting the output side of SR(7) 210 which is connected to "W" gates register 117 through lines S(0-7) and thence to Z OR gates 83.

Connected to both SR(7) 210 and relative address register 205 is timing chain circuit 215 whose purpose is to trigger the gating of information through the registers. The circuit for timing chain 215 is shown in FIG. 14A and comprises ten serially connected monostable flip-flops 217 through 226 having output lines labelled T(0-9) respectively.

It will be noted that the other outputs of flip-flops 218 through 225 are connected to the input side of OR gate 227 whose output is connected to three serially connected monostable flip-flops 230 through 232 defining a sub-timing chain 229 with outputs labelled T(a), T(b), and T(c).

FIG. 14B is a circuit diagram of add-subtract sequence logic unit 238.

Unit 238 comprises eight sequence dual input AND gates 239 whose input side is connected to lines T(1-8) and whose other input side is connected in common to line T(a). The output lines of ANDgates 239 are labelled T(1)a through T(8)a and are connected variously to an input of multiple input sequence OR gates 240, four in number, the upper two having output lines labelled U(0-1) going to X-adder 203 and the lower two having output lines labelled U(2-3) going to Y-adder 204.

A function of logic unit 238 is to sequentially instruct the adders to increment or decrement by one binary digit the address of the "point" 26 around which the sequence is taking place.

A signal on line U(0) (from lines T(1)a, T(2)a and T(8)a) directs X-adder 203 to add one to the "point" address.

A signal on line U(1) (from lines T(4)a, T(5)a and T(6)a) directs X-adder 203 to subtract one from the "point"address.

A signal on line U(2) (from lines T(2)a, T(3)a and T(4)a) directs Y-adder 204 to add one to the "point"address.

A signal on line U(3) (from lines T(6)a, T(7)a and T(8)a) directs Y-adder 204 to subtract one from the "point" address.

Thus, depending on which of lines T(1a-8a) is activated, one binary digit is added to or subtracted from the address of the "point"around which the sequence is taking place.

Sequence AND gates "c" 241 have one input connected to T(c) and the other input connected variously to T(1-8) and has its outputs labelled T(1c-8c).

Referring again to FIG. 14, interrupt OR gate 207 is provided whose input is connected to line A(6) from primary input register 101 and also to lines XUNFand XOVF from X-adder 203 and lines YUNF and YOVF from Y-adder 204, and line I(1) from circuit 95.

Another OR gate 208 is provided in circuit 152 which is used to activate command line *06 when line T(9) is activated in order to transfer the status of the Z OR gates 83 to Z-output register 84 as described previously.

Operation:

To begin the process of reading out the addresses of a locus of points, line T(0) is activated by a pulse on line I(O) from the computer to gate the initial X- and Y-address information into base address register 200.

Activation of line T(0) of timing chain circuit 215 begins the search sequence to interrogate all points immediately adjacent the addressed point.

It will be noted from FIG. 14A and as shown in timing diagram (FIG. 15) that the sub-timing chain 229 subdivides each timing chain pulse T'(1-8) into three sub-pulses such that the main timing chain pulse has within it a subtiming chain pulse 235, 236 and 237 corresponding to the output pulse of one-shot flip-flops 230, 231 and 232 respectively, on lines T(a), T(b) and T(c).

It will be noted that line T(a) is connected to sequence decoder 238 and thence to X- and Y-adders 203 and 204, T(b) is connected to the "clock" input of flip-flops 206 of register 205 and T(c) is connected to sequence decoder 238 and thence to the clock inputs of flip-flops 212 of SR(7) 210.

Sequence AND gates "c" 241 are similar to sequence AND gates "a" 239 in that they produce a pulse at their outputs when timing chain pulses T(1-8) and the sub-timing chain pulses T(a), T(b) and T(c) coincide.

The function of activation of T(a) is to direct X- and Y-adders 203 and 204 to either add "one," subtract "one" or leave unchanged the X- and Y-address of a particular point 26.

Around a particular point 26 will be eight immediately adjacent points which will be labelled according to the points of a compass beginning counterclockwise from east "E" to "NE" etc. Table 6 is a tabulation of one cycle of the search routine which is executed for each point during the increment operation.

TABLE 6

Loc- ation Time Operation T(0) Address X, Y, in base register E T(1) a. Add 1 to X in base register 200 b. Store X plus 1, Y in register 205 c. Read drawingboard ROR NE T(2) a. Add 1 to X, and 1 to Y in base register 200 b. Store X plus 1, Y plus 1 in register 205 c. Read drawingboard ROR N T(3) a. Add 1 to Y in base register 200 b. Store X, Y plus 1 in register 205 c. Read drawingboard ROR NW T(4) a. Subtract 1 from X, add 1 to Y in register 200 b. Store X minus 1, Y plus 1 in register 205 c. Read drawingboard ROR W T(5) a. Subtract 1 from X in base register 200 b. Store X minus 1, Y in register 205 c. Read drawingboard ROR SW T(6) a. Subtract 1 from X, subtract 1 from Y in register 200 b. Store X minus 1, Y minus 1 in register 205 c. Read Drawingboard ROR S T(7) a. Subtract 1 from Y in base register 200 b. Store X, Y minus 1 in register 205 c. Read drawingboard ROR SE T(8) a. Add 1 to X, subtract 1 from Y in register 200 b. Store X plus 1, Y minus 1 in register 205 c. Read drawingboard ROR T(9) Transfer contents of SR(7) through "W" gates 117 to Z-output register 84 __________________________________________________________________________

Assuming the XDC and YDC bits of SR(0) are activated, then as each point is sequentially selected by the timing chain 215 and read from array 35, its state is stored in Status Register SR(7) 210. After the states of the eight surrounding points have been collected in SR(7) 210, then the contents are transferred on lines S(0-7) to "W" gates 117 as noted in Table 6 at time T(9) and thence to drawingboard output register 73 (Z-output register 84).

Upon conclusion of a search routine, the address of the adjacent activated points may be used to begin the next search routine.

When the locus of points ends at a border or side of array 35, overflow and underflow signals will occur in either the X- or Y-adders 203 and 204, respectively. When an underflow or overflow occurs in either the X- or Y-direction, one of lines XUNF, XOVF, YUNF or YOVF will be activated to cause a signal to be impressed on line I(1) at the output of OR gate 207 to terminate the increment operation.

However, if the operator wishes, he may ignore an overflow and use the truncated address to start at the first column or row again. For example, the address of a point in the last column would have a binary X-address of "1111." adding "1" gives an X-address of "10000;" truncating the overflow bit gives "0000," which is just the X-address of a point in the first column.

The other three boundary conditions namely; decrement X from 0000 to X equals 1111; increment Yfrom 1111 to Y equals 0000; and decrement Yfrom 0000 to Yequals 1111 behaves similarly.

Claims

I claim:

1. A graphical input-output device for a computer comprising a plurality of light emitter-sensor circuits juxtaposed in a common plane and arranged in ordered array, means for electrically activating and deactivating said light emitters, means for emitting radiant energy for activating said light sensors, means for connecting said emitter-sensor circuits to a computer, and means for controlling the flow of information represented by the activated and inactivated status of said emitters from and to said computer.

2. The graphical input-output device for a computer as claimed in claim 1 wherein said means for electrically activating and deactivating said light emitters includes means for identifying by an address each emitter-sensor circuit according to a code, means for decoding a given address and activating said emitter at said address, means for encoding the address of an activated emitter and means for transmitting said encoded address to said computer.

3. The graphical input-output device for a computer as claimed in claim 1 wherein said means for electrically activating and deactivating said light emitters includes means for identifying by an address various sub-pluralities of emitter-sensor circuits, means for activating said emitters of said sub-pluralities, means for encoding said address and means for transmitting said encoded address to said computer.

4. The graphical input-output device for a computer as claimed in claim 1 wherein said means for controlling the flow of information represented by the activated and inactivated status of said emitters comprises means for receiving information from said computer and distinguishing between control information and address information, and means for controlling the flow of coded and decoded address information into and out of said plurality of emitter-sensor circuits using said control information.

5. The graphical input-output device for a computer as claimed in claim 1 wherein said plurality of light emitter-sensor circuits are arranged in rows and columns, said rows defining a Y-direction or coordinate and said columns defining an X-direction or coordinate.

6. The graphical input-output device for a computer as claimed in claim 1 wherein said means for activating said sensors is a penlight comprising a write end and an erase end, a light source at each of said ends, means for activating said light sources, means for connecting said penlight to said means for electrically activating and deactivating said light emitters and means for connecting said penlight to said means for controlling the flow of information from and to said computer.

7. The graphical input-output device for a computer as claimed in claim 6 wherein said penlight write end comprises means for marking a surface and said penlight erase end comprises means for removing marks made by said means for marking.

8. The graphical input-output device for a computer as claimed in claim 6 wherein said penlight comprises means for controlling the intensity of said light sources.

9. The graphical input-output device for a computer as claimed in claim 1 wherein said emitter-sensor circuit comprise means for maintaining said light emitter in the activated state when activated and in the deactivated state when not activated.

10. The graphical input-output device for a computer as claimed in claim 9 wherein said means for maintaining said light emitters in either the activated or deactivated state comprises a pnp-npn transistor pair.

11. The graphical input-output device for a computer as claimed in claim 1 wherein said emitter-sensor circuit comprises means for storing information concerning the activated and inactivated status of said emitter.

12. The graphical input-output device for a computer as claimed in claim 1 wherein said ordered array of said light emitter-sensor circuits comprises means for activating all of said emitters from a common circuit, means for deactivating all of said emitters from a common circuit and means for detecting the status of all of said individual emitters from a common circuit.

13. The graphical input-output device for a computer as claimed in claim 1 wherein said emitter-sensor circuits comprise means for detecting light intensities by said light sensors and means for controlling the light intensity emitted by said light emitters.

14. The graphical input-output device for a computer as claimed in claim 1 wherein said emitter-sensor circuits comprise means for individually controlling the intensity of light emitted by each of said light emitters.

15. The graphical input-output device for a computer as claimed in claim 1 wherein said emitter-sensor circuits comprise means for controlling the intensity of light emitters.

16. The graphical input-output device for a computer as claimed in claim 1 wherein said light emitter-sensing circuits comprise means for emitting light, means for energizing said means for emitting light and means for deenergizing said means for emitting light.

17. The graphical input-output device for a computer as claimed in claim 16 wherein said means for energizing said means for emitting light comprises means for detecting radiant energy and said means for deenergizing said means for emitting light comprises means for detecting radiant energy.

18. The graphical input-output device for a computer as claimed in claim 16 wherein said means for energizing said means for emitting light comprises a transistor and said means for deenergizing said means for emitting light comprises a transistor.

19. The graphical input-output device for a computer as claimed in claim 16 wherein said means for emitting light is a light emitting diode.

20. The graphical input-output device for a computer as claimed in claim 16 further comprising means for detecting the activated or inactivated status of said mean for emitting light.

21. The graphical input-output device for a computer as claimed in claim 1 wherein said means for controlling the flow of information from and to said computer includes means for interrupting the flow of information to said computer.

22. The graphical input-output device for a computer as claimed in claim 1 wherein said means for controlling the flow of information from and to said computer comprises a drawingboard processor unit, means for placing information into said array, and means for reading information represented by the activated or inactivated status of said emitters out of said array.

23. The graphical input-output device for a computer as claimed in claim 22 wherein said means for placing information into said array comprises an input register having input and output lines, and an input parts register having input and output lines, said output lines of said input register connected to said emitter-sensor array, said input lines of said input register connected to said output lines of said input parts register and said input lines to said input parts register connected to said processor unit.

24. The graphical input-output device for a computer as claimed in claim 22 wherein said means for reading information out of said array comprises an output register having input and output lines an output parts register having input and output lines, and a drawingboard output register having input and output lines, said input lines of said output register connected to said array, said output lines of said output register connected to said input lines of said output parts register, said output lines of said output parts register connected to said input lines of said drawingboard output register and said output lines of said drawingboard output register connected to said computer.

25. The graphical input-output device for a computer as claimed in claim 23 further comprising means for decoding addresses defining a particular emitter-sensor circuit of said array having an input and an output, said output connected to said input parts register, said input connected to said drawingboard processor unit.

26. The graphical input-output device for a computer as claimed in claim 24 further comprising means for encoding addresses defining a particular emitter-sensor circuit of said array having an input and an output, said input connected to said output register and said output connected to said drawingboard output register.

27. The graphical input-output device for a computer as claimed in claim 22 wherein said drawingboard processor unit comprises means for receiving coded address and control information from an incoming signal and distinguishing said address information from said control information, means for decoding said control information having an input and an output, said input connected to said means for receiving coded information, means for decoding said address information having an input and an output, means for interconnecting the output of said means for decoding of said control information for control of flow of address information to said array of said emitter-sensor circuits.

28. The graphical input-output device for a computer as claimed in claim 26 wherein said drawingboard processor unit further comprises means for encoding address information in accordance with the active or inactive status of said emitter-sensor circuits of said array and means for interconnecting the output of said means for decoding control information and said means for encoding said address information for control of flow of address information out of said array of emitter-sensor circuits to said computer.

29. The graphical input-output device for a computer as claimed in claim 22 wherein said drawingboard processor unit includes means for associating a label with the activated or inactivated status of emitters in said array.

30. The graphical input-output device for a computer as claimed in claim 22 wherein said drawingboard processor unit includes means for storing address and control information for later use in operating said device.

31. The graphical input-output device for a computer as claimed in claim 22 wherein said means for reading information includes means for detecting incremental variations in graphical information displayed in said array.

32. The graphical input-output device for a computer as claimed in claim 30 wherein said drawingboard processor unit further comprises a primary input register for receiving address and control information from said computer and means for transferring said address information into said means for storing address and control information and means for transferring address and control information out of said means for storing address and control information to operate said array.

33. The graphical input-output device for a computer as claimed in claim 1 wherein said emitter-sensor circuit comprises means for controlling the sensitivity of said light sensors to various levels of light intensity.