SU1200306A1 - Device for reading information - Google Patents

Abstract

A DEVICE FOR READING INFORMATION, containing a scanning unit. The output of which is connected to the inputs of the first pulse shaper, the element NOT and the first input of the first element 2I-STI, the first element And, the inputs of which are connected to the outputs of the first and second pulse formers, the second element And, one input is connected to a pulse generator, the other is connected to the output of the first trigger, and the output is connected to one counter input, the third pulse generator, the input of which is connected to the photoelectric sensor output signals, and the output is connected to one input of the second trigger, the reset signal shaper, the output of which is connected to one input of the first trigger, the other input of which is connected to the output of the first And element, to another input of the second trigger and to one input of the decoder, the other inputs are connected with the outputs of the counter, and the shift register, characterized in that, in order to increase accuracy, it contains an AND-NOT element, whose inputs are connected to the outputs. element and the second trigger, the third trigger, whose inputs are connected to the outputs of the element AND-NOT and the reset signal generator, and the output is connected to the second input of the first element 2I-OR, the third input of which is connected to the output of the first trigger, fourth trigger, inputs which is connected to the outputs of the first and i second pulse formers, and the output is connected to the first input re (L shift bias, the second input of which is connected to the reset signal shaper, the fifth trigger, the inputs of which are connected to the decoder, the third element t And, the inputs of which are connected to the outputs of the first element I and the fifth trigger, and the output is connected to another input of the counter, connected in series with a trigger, & 0 whose inputs are connected to the outputs O of the counter and the decoder, and the second element 2И-Ш1И, the other inputs of which are connected to the outputs of the third element And and the counter, and the output is connected to the third input of the shift register.

Description

 one

The invention relates to the field of automation and computer technology and can be used to read information, in particular, to read a code printed on a carrier in the form of a combination of reflective and non-reflective surface areas.

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

The drawing shows the block diagram of the device.

The device includes a scanning unit 1, a HE element 2, a photoelectric sensor 3 signals, a driver 4 reset signals, a shift register 5, the first 6, the second 7, the third 8, the fourth 9, the fifth 10 and the sixth 11 triggers, the first 12, the second 13 and third 14 pulse formers, the first 15 and second 16 elements 2I-ILY, the first 17, second 18 and third 19 AND elements, AND-NOT 20 element, counter 21, decoder 22 and pulse generator 23.

The device works as follows.

A silicon wafer with a code printed on it is used as the information carrier. The code is the alternation of areas with different reflection coefficients, and the length of the area with one refractive index value is the product of the area length, corresponding to one code bit, and the number of adjacent bits having the same value.

After installing the plate, it is oriented so that the code is located along the path of the scanning beam of unit 1, and the beginning of the carrier, where the code is written, coincides with the photoelectric sensor 3, and then the plate is fixed in this position. From block I, the signal arrives at the driver of 12 pulses and element 2I-OR 1.5, the first of which causes it, whose signal is on the falling edge of the input signal, and the second permits the signal to pass, and the second allows the signal of the block 1 to pass to the driver of 13 pulses or . from trigger 8 or trigger 6. Shaper 13 generates a pulse on the leading edge of the signal from block 1. Photoelectric sensor 3

00306.

It melts from the light falling from the reading head of block 1.

Sensor 3 is located below the carrier installation level and the light signal ends on it later than the appearance of the reflected signal from the carrier on the photodetector unit 1.

On the falling edge of the signal from the photoelectric sensor 3, the forma- tion of the iO Tel 14 emits a pulse, which

sets trigger 7 to

II1 ti

I.

The element AND-NOT 20 in the presence of 1 at the output of the trigger 7 and the presence of O) 5 at the output of block 1 generates a signal O, which sets the trigger 8 to

one

state

The pulses of the formers 12 and 13 set trigger 9 to the state O or 1, respectively, as well as trigger

1. Element and 18

ger 6

in the It It state with the trigger 6 issues

on signal

counting pulses from the generator 23 to the input of the counter 21. The latter reads the number of pulses at a constant speed of movement of the reading head of the block 1.

The trigger 11. outputs the enable signal to the element 2I-OR 16 at that moment in time when the counter 21 has calculated the minimum number of pulses per one bit.

The trigger 10 provides an enable signal for the output signal to pass from the drivers 12 and 13 in those

time of reliable occurrence of the input signal. Element And 19 generates a signal to reset the counter 21 by a signal to change the code regardless of whether the counter counted 21

average number of pulses corresponding to one code bit. 3) Iment 2-OR 16 generates a sync pulse to shift register 5 either from the input signal through element 1 9, or from

5 of counter 21, when it misses the number of pulses averaged by one bit.

When arriving from the clock element 16, register 5 writes the value O or I to its bit, depending on the state of trigger 9.

At each new sync pulse, register 5 records information from trigger 9, the shift previously recorded by one bit. The number of sync pulses is equal to the number of code bits, and the state of trigger 9 corresponds to the state of the pad surface, which is the physical execution of the code.

Claims (1)

A DEVICE FOR READING INFORMATION, containing a scanning unit., The output of which is connected to the inputs of the first pulse shaper, the element NOT and the first input of the first 2I-OR element, the first element And, the inputs of which are connected to the outputs of the first and second pulse shapers, the second element And, one input of which is connected to the pulse generator, the other is connected to the output of the first trigger, and the output is connected to one input of the counter, the third pulse shaper, the input of which is connected to the output of the photoelectric sensor The output is connected to one input of the second trigger, a reset driver, the output of which is connected to one input of the first trigger, the other input of which is connected to the output of the first AND element, to another input of the second trigger and to one input of the decoder, the other inputs of which are connected with counter outputs, and a shift register, characterized in that, in order to increase accuracy, it contains an AND-NOT element, the inputs of which are connected to the outputs. the NOT element and the second trigger, the third trigger, whose inputs are connected to the outputs of the NAND element and the reset driver, and the output is connected to the second input of the first 2AND — OR element, the third input of which is connected to the output of the first trigger, the fourth trigger, inputs which is connected to the outputs of the first and second pulse shapers, and the output is connected to the first input of the shift register, the second input of which is connected to the reset signal shaper, the fifth trigger, the inputs of which are connected to the decoder, the third element And, the inputs to otorogo connected to the outputs of the first element And the fifth trigger, and the output is connected to another input of the counter, the sixth trigger is connected in series, the inputs of which are connected to the outputs of the counter and decoder, and the second element 2I-IPI, the other inputs of which are connected to the outputs of the third element And and a counter, and the output is connected to the third input of the shift register.