SU1718252A1 - Device for reading graphic information - Google Patents

Abstract

This invention relates to automation and computing. The purpose of the invention is to increase the speed of the device. The goal is achieved by reducing the time to determine the coordinates, which is ensured by the introduction of a decoder, a ring register and an OR element and the corresponding functional links with the remaining elements of the device. 2 Il.

Description

The invention relates to computing technology, in particular to the coding of graphic information, and Can be used in complexes of design automation equipment, as well as in systems for processing cartographic and other graphic information.

The purpose of the invention is to increase the speed of the device.

Figure 1 presents the block diagram of the device; Fig. 2 shows a constructive implementation of the shear and memory assembly.

The device contains a tablet 1, a 2 coordinate pickup, a pulse generator 3, a coordinate determination unit 4 including a memory offset node 5, a reversible counter 6, an amplifier 7, a decoder 8, a switch 9 having a decoder 10 and a group of amplifiers 11, an output register 12 and the element OR 13.

The shift and memory node 5 (FIG. 2) contains a ring shift register 14, a pulse shaper 15, AND elements 16 and triggers 17. In addition, inputs 18 and 19 and outputs 20 and 21 are shown.

The device works as follows.

In the initial state, the puller 2 of the coordinates is in a certain position on the field of the tablet 1, all the triggers 17 and the counter 6 are in the zero state, in the first discharge of the register 14 is written 1, its other bits are zeroed. Register 12 is reset.

At the time of setting the first bit of register 14 to the single state, the signal from its output goes to the first shaper 15, producing a short pulse, according to which the trigger 17 is set to the single state.

The first trigger 17 is the most significant bit that forms the binary equivalent of the current bus number of a given coordinate, and the last one is the least significant bit. Thus, the determination of coordinates begins with the highest bit of the binary equivalent.

In the decoder 10, a signal is generated to the bus with a number, the binary equivalent of which is contained in the triggers 17. Through the appropriate amplifier 11, form the

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The required pulse of the required parameters is generated by the signal from the generator of 3 pulses, the corresponding tire of tablet 1 is excited. In this case, depending on the position of the puller 2 coordinates (center of its coil), polling pulses are generated either at one or the other output of the amplifier 7. If the polled bus lies to the left of the center of the puller coil 2, then a pulse is formed at the second output of the amplifier 7 and goes to the subtracting input of the reversing counter 6. If the tire lies to the right, i.e. its number is larger than the number closest to the center of the bus puller coil (from the puller), the signal arrives at the first output of the gated signals from the pulse generator of amplifier 7 to the summing (first) input of counter 6, the bits outputs of counter 6 are connected to the inputs of the decoder 8.

The operation algorithm of the counter 6 together with the decoder 8 is as follows.

The decoder 8 generates a signal at its first output in the case when the difference between the number of right and left pulses received by the counter is the number of pulses specified by it (this is determined by the accuracy requirements for determining the coordinates). If the number of left pulses is greater than the number of right pulses, a signal is generated at the second output of the decoder 8, which, arriving at AND 16, opened by the signal from the first output of register 14, resets the trigger 17 to the zero state. The signal from the OR element 13, which is formed at any signal from the output of the decoder 8, resets the counter 6 to the initial (zero) state, outputs a clock signal to the register 14, by which 1 is shifted to the next bit, after which the procedure is repeated.

This happens until the last bit of register 14. After the decoder 8 is triggered on this bit, 1 is rewritten to the first digit of register 14 from the last, and on the front of the signal from

the output of the last bit of register 14 (on the falling edge) by the signal from output 20 supplied to the synchronous input of register 12 is written to it the contents of all bits of the trigger 17, this content is the binary equivalent of the coordinate number fixed by the remover 2 coordinates.

Claims (1)

Invention Formula A device for reading graphic information containing a tablet made in the form of a system of two mutually orthogonal coordinate lines, inputs which are connected to the switch, coordinate remover, the output of which is connected to one amplifier input, the other input of which is connected to the output of the pulse generator, the output register, the output of which is an information output of the device, a reversible counter, pulse shapers, AND elements and triggers, which is different from the fact that, in order to increase the speed of the device, it contains a decoder, the information input of which is connected to the output of a reversible counter, a ring shift register, clocking output of which is connected to the synchronization input of the output register, and information outputs are connected to the inputs of the corresponding pulse formers and to the same inputs of the And elements, the other inputs of which are connected to the corresponding output of the decoder, and the outputs connected to the zero inputs of the corresponding triggers, single inputs of which are connected to the outputs of the corresponding pulse shapers, and the outputs are connected to the information inputs of the output register and switch, and the OR element, whose inputs are connected to the outputs of the decoder, and the output is connected to the setup input of the reversible counter and the clock input ring register shift, while the clock input of the switch is connected to the output of the pulse generator.