SU922818A1 - Graphic information reading-out device - Google Patents

Description

The invention relates to automation and computing, and can be used as an input device for the operational conversion of $ and input in a computer drawing and graphic information, and also included as an input device in the main complex of devices of a universal computer, and also effectively use- (θ Xia in various specialized computer-aided design systems.

A device for reading. _ς graphic information containing a tablet with a matrix of coordinate buses, a puller of coordinates with an amplifier of induced signals, commutators of coordinate buses connected to a pulse distributor connected to a pulse generator and through a decoder of operations to a counter of operations, counters of coarse and precise readings, block reference, signals, single pulse generator, code transmission gates, delay lines and OR circuits [1}.

A disadvantage of this device is the low accuracy of reading the coordinates when changing the thickness of the media.

The closest to the proposed technical solution is a device that contains a tablet with two differently orthogonal groups of coordinate tires, a rough count counter, outputs via switches connected to the inputs of the coordinate tires of the tablet, an exact count counter, a coordinate remover, through an amplifier connected to one input of the comparison circuit , the control unit, the input of which is connected to the output of the comparison circuit, and the outputs are connected to the inputs of switches, with coarse and precise counters, and a unit for forming reference impulses a readout current inputs connected to the outputs of the coordinate plate tire, and the control input of - a counter accurate reading, the output of said unit is connected to another input of the comparison circuit [2].

However, the known device is also not high enough accuracy.

The purpose of the invention is to improve the accuracy of the device.

This goal is achieved by the fact that in the device containing a tablet with a matrix of coordinate tires connected to the unit of formation of the reference pulses and to the outputs of the corresponding 3

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switchboards, the inputs of which are connected to the first counter and to the pulse distributor, a shift register connected to the output of the OR element and to the same inputs of the pulse distributor, the other input of which is connected to the pulse generator, and the outputs are connected to the first, second and third counters , with pulse formers and with element H, the first amplifier is a driver, 10 connected to the output of the coordinate remover, the second amplifier is a driver connected to the unit for forming reference pulses, the input of which is not with the second counter, and to the one input of the comparator, the output of which is connected to one input of the OR element, and elements AND groups whose inputs are connected to the first <counter and to the output of the AND element, and the output is the device's output, the fourth counter is entered connected to the pulse distributor and to the inputs of the elements of the AND group, the inverter. connected to the first amplifier, shaper, to the distributor of the impulses and to the other input of the comparator, and the adder, whose inputs are connected to the second and third counters, with first forms rovatelem pulses and the distributor 'pulses, and the output 30 is connected to the AND gate, whose output is connected to another input of the OR gate, the outputs of the second pulse generator is connected to first and second counters. 35

The drawing shows the block diagram of the device.

The device includes a tablet 1 with coordinate buses, switches 2 and 3, the first counter 4, the unit 5 for forming reference pulses, the coordinate remover b. · The first amplifier —former 7, the inverter 8, the comparison unit 9, the second amplifier —former 10 , control unit 11, second-45 swarm counter .12, third counter 13, division unit 14, first 15 and second 16 pulse shapers, and elements 17 and groups. At that, block 5 contains switch 18, reference conductors 19 and position signal sensor 20, block 11 contains a pulse generator 21, shift register 22, OR element 23 and pulse distributor 24, and block 14 contains a fourth counter 25, adder 26 and EL- ⁵⁵ Note 27 And ...

The device works as follows.

At the initial moment of time, all device counters and adder 26 60

set to the zero state, in the register 22 the unit is written in the ^ lth digit.

By setting the puller 6 coordinates to the read point, the operator pressing 65

Start button (not shown) turns on the device, starting pulse generator 21. The pulses from the output of the control unit 11 counts the reversible counter '4, choosing the corresponding key of the first and second switches 2 and 3, performing a sequential search of the tires of the plate 1, and simultaneously the pulses coming to (the first switch 2, provide current flow through the chain: the selected bus X of tablet 1 is the reference conductor farthest from the sensor 20 19. The signals in the puller 6 coordinates and the sensor 20 are received by the signals coming through the first 7 and second 10 amplifiers. - the formers, respectively, to the inputs of block 9, where Dates them until the amplitude of the signal. From the puller 6 coordinates does not exceed the amplitude of the signal from the position sensor 20, then block 9 generates a signal which, passing through the element 23 OR, enters the input of the register 22. The new state of register 22 corresponds to refinement of a roughly defined coordinate.

The pulses from the output of block 11 count the counter 13 and the counter 12, choosing the appropriate one; the key of the third switch 18, carrying out a sequential search of the reference conductors 19, starting with the position closest to the sensor 20, and simultaneously pulses with. unit 11 provide the flow of current pulses along the chain: selected in the first stage, the tire X tablet 1 - reference conductor 19.

As soon as the amplitude of the signal from the puller b coordinates exceeds the amplitude of the signal from the sensor 20, the signal from the output of block 9 will transfer, register 22 to the next state, while the output of block 11 will have a high potential, on the leading front of which the driver of 16 pulses will form a short pulse the counter 12 will reset to zero, and arriving at the input of the subtraction of the reversible counter '4, subtract one from it, which corresponds to one backward bounce and the choice of the previous tire on tablet 1. At the same time, the signal from the puller 6 coordinates n Changes polarity. Block 11 ^- in this state, register 22 outputs the second potential and pulses, counter 13 adds them to its contents, counter 12 counts their number by sequentially iterating the reference conductors 19, again, as in the previous state of the shift register 22, determining the updated x coordinate , with the difference that the high potential at the output of the block 11, acting on the inverter 8, inverts the signal from the coordinate remover “,” thanks to which the signal to

five

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the output of block 9 becomes positive again.

As soon as the signal aplity from the puller of coordinates b exceeds the amplitude of the signal from sensor 20, the signal from block 9 transfers register 22 to a new 5 state, "while in the counter 12 the updated code from (P-1) tablet bus 1 is recorded, and in counter 13 - the sum of the refined codes from P and (P-.1) tires of tablet 1. In the new state, the block '11 th sends impulses to the entrance to ₅ and a low level to the output to the _first , on the front of which (the level difference from high to low) pulse generator 15 outputs a pulse, transmitting the contents of the counter 15. 12 reference in ^x adder 26, starting with the corresponding first digit, which corresponds to multiplying the contents of the counter 12 by a specified value. · 20

The pulses at the output in $ 11 of the block counts the counter 25 and for each of these impulses arriving at the control input of the adder 26, a result occurs. goes the subtraction from the contents of the sum-_ of the torus of the contents of the counter 13, thereby producing the division. As soon as the sign bit of the adder 26 as a result of the next subtraction is set to "one", which corresponds to a negative number in the adder 26, a high potential will be fed to the One input of the element 27 And the pulse from the output of the block 11, passing through the element 27 And will transmit the code the X coordinates through the elements 17 AND of the group of code 35 to the output of the device, the upper bits of the code from the reversible counter 4, and the young bits to the output from the counter of 25 cycles, reset all the counters to the initial state, and passing through the element to 23 OR, translates register 22 into new state s, corresponding to the definition of the coordinate Y, similar to what is happening, as well as the coordinates of X.. ·

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The introduction of new nodes and new constructive links can significantly improve the accuracy of the device when changing the thickness of the media. 50

Claims (1)

A device for reading graphic information containing a tablet with a matrix of coordinate buses connected to a unit for generating reference pulses and to the outputs of corresponding switches, whose inputs are connected to the first counter and to the pulse distributor, a shift register connected to the output of the OR element and with one inputs pulse distributor, the other input of which is connected to the pulse generator, and the outputs are connected to the first, second and third counters, to the pulse shapers and to the element , the first amplifier-former connected to the output of the coordinate remover, the second amplifier-former connected to the unit for forming reference pulses, the input of which is connected to the second counter, and to one input of the comparison unit, the output of which is connected to one input of the OR element, and the elements AND groups whose inputs are connected to the first counter and to the output of the element I, and the output is the output of the device, which is similar to the fact that, in order to improve the accuracy of the device, it contains the fourth counter connected to the distributor pulses and with the inputs of elements And groups, an inverter connected to the first amplifier - driver, to the pulse distributor and to another input of the comparison unit, and an adder, whose inputs are connected to the second with the third counters, the first pulse driver and to the pulse distributor, and the output is connected to the element AND, the output of which is connected to the other inputs of the element OR, while the output of the second pulse shaper is connected to the first and second counters.