SU1495827A1 - Device for reading out information from punched medium - Google Patents

Abstract

The invention relates to computing and can be used to enter information into a computer. The aim of the invention is to increase the reliability of reading information. A threshold element, logic elements, and an adder are introduced into the device to optimize the moment of recording the string information read from the mobile carrier, as well as minimize the time for polling the code bits of the carrier string. 1 il.

Description

The invention relates to computing and can be used to enter information into a computer.

The aim of the invention is to increase the reliability of the communication of information.

The drawing shows a functional diagram of the device.

The device contains a unit 1 photodetectors, a threshold element 2, the first 3, the second 4, the third 5 elements AND, the first element OR NOT 6, the fourth element AND 7, the element NOT 8, the unit 9 comparison, the first element OR 10 ,, the first 11, the second 12 and third 13 registers, block 14 amplifiers, the second element OR 15, the memory block 16, the counter 17, the second element OR-NOT 18, the fifth 19, the sixth 20, the seventh 21 and the eighth 22 And elements, the first 23 and the second 24 triggers, generator 25 pulses, adder 26, input 27 of the initial installation.

The threshold element 2 contains the decoder 28, the counter 29 and the element; NOT 30.

The device works as follows.

The initial setup signal, which is applied to the device input 27, zeroes the counter 17, triggers 23, OR 15 through the registers 11–13 and OR 10 through the element. counter 29. Trigger 23 prepares elements 19 and 20 for opening. After that, a generator of 25 pulses turns on and clocks are supplied to the device, which are fed to the clock input of trigger 24 and inputs of elements E 19 - 22. Trigger 24 operates in counting mode and together with elements And 19 and 20 forms two clock sequences of impulses shifted relative to each other. Moreover, the clock pulses from the output element And 19 provide recording

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in register 13, and the pulses from the output of the element And 20 interrogate the elements And 3 - 5 and thus the outputs of the comparison block 9. In the absence of information on the outputs of block 14, registers 11-13 are in the zero position. Therefore, a signal is generated at the first output of block 9, which opens the element

ment And 3. The pulses of element 20 through element 3 are fed to the input of threshold element 2. Counter 29 is filled up to a threshold value, which is determined by decoder 28, after which the counter control input signal e is removed through element NOT 30 and the count of pulses in threshold element 2 is terminated. This state of the device is maintained until the movement of the perfume medium is switched on. When the perfonitel is moving, a number of perforations of the readable line falls under block 1 of the photodetectors.

At the corresponding outputs of block 1, the code of the line is generated, the single signals of the bits of which are fed to the information inputs of the register 13. When the next clock pulse is applied from the output of the element 19, the line code is written to the register 13. In this case, the adder 26 calculates the sum of the single bits code of the line recorded in register 13 and generates the corresponding binary sum code, which is fed to the comparison block 9 and to the information inputs of the register 11. At the beginning of the line, the number at the output of the adder 26 is greater than the number (zero

computes to the true number of perforations of a given line. Moreover, in each subsequent write cycle in register 13, the number at the output of adder 26 is compared with the number recorded in register 12 in the previous cycle, and the corresponding line code is recorded in register 11, since the time spent on the line of photo detectors is much longer than the clock period. sequences of pulses generated by elements And 19 and 20, then when comparing the specified numbers, the following 15 situations arise: at the beginning of the line (upper perforation line) the number of sum of the matrix 26 is greater than the number in register 12 in the middle of the number string lo adder 26 is equal to the number in the register 12; at the end of the line (the lower limit of perforations is the number of the adder 26 is less than the number in the register 12.

In this case, the equality of the numbers in the middle of the line at a given speed of movement of the carrier and the clock frequency is maintained for a certain number of cycles, the minimum number of which is taken as a threshold value, fixed by threshold element 2 and is a sign of the true code value of the read line. As long as the number of the adder 26 is greater than the number of the register 12, the signal at the second output of the comparison block 9 keeps the element 4 open and the clock pulses the threshold element 2 and then rewrites the sum of the units of the line code from the adder 26 into register 12, and the current code of the line from register 13 in

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register 12, therefore, block 9 generates 40 register 11. If the specified

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computes to the true number of perforations of a given line. Moreover, in each subsequent cycle of writing to register 13, the number at the output of adder 26 is compared with the number recorded in register 12 in the previous cycle, and the corresponding line code is fixed in register 11. Since the time spent by the carrier under the photodetectors is significantly longer than the period of clock sequences of pulses, formed by the elements And 19 and 20, then when comparing the specified numbers, the following situations arise: at the beginning of the line (upper perforation test) the number of the adder 26 is greater than the number in register 12; in the middle of the line, the number of the adder 26 is equal to the number in the register 12; at the end of the line (lower perforation boundary), the number of the adder 26 is less than the number in register 12.

In this case, the equality of the numbers in the middle of the line at a given speed of movement of the carrier and the clock frequency is maintained for a certain number of clock cycles, the minimum number of which is taken as a threshold value, fixed by threshold element 2 and is a sign of the true code value of the read line. As long as the number of the adder 26 is greater than the number of the register 12, the signal at the second output of the comparison block 9 keeps the element 4 open and the clock pulses the threshold element 2 and then rewrites the sum of the units of the line code from the adder 26 into register 12, and the current code of the line from register 13 in

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the signal at the second output, which opens the AND 4 element, removes the signal at the first output and closes the H 3 element. A clock pulse from the output of the AND 4 element through the OR 10 element is about the 45th threshold element 2 to the threshold

the counter 29 of the threshold element 2 is supplied to the element OR-NOT; 6, at the output of which a negative (th pulse) is formed. On the leading edge

of this pulse, the sum of the units from the output has advanced under the photodetector-adder 26 is rewritten to register 12, and the code of the line in the current clock cycle from the outputs of register 13 to the register.

ki of block 1 or there was a skew of the carrier; in the next cycle, the signal More will form again and the threshold element will be reset or the signal on

During the movement of the information carrier, the third output of block 9, which reads the line code and the number of perforations of the read line, recorded respectively in registers 13 and 1.1 and adder 26, successively primesh element 7 and a clock pulse from its output nukes threshold element 2 and changes the state of registers 11 and 12, but if equality compares block 9 closes element 4 and outputs a signal that opens element 3. The clock pulses through element 3 are filled in successively. In this case, the code of the string in register 11 does not change. If the equality of numbers is not stable, by chance, for example, the carrier string has not yet fully advanced under the photoreceiver.

ki of block 1 or there was a skew of the carrier; in the next cycle, the signal More will form again and the threshold element will be reset or the signal on

the third output of block 9, which opens element 7 and a clock pulse from its output, nulls threshold element 2 and changes the state of registers 11 and 12, but if the equality of comparison of numbers is stable, threshold element 2 fills up to its threshold threshold and issues a signal which, through element 30, closes the element AND 7 and prepares the element AND 5 for opening. If, upon further advancement of the carrier, the equality of the compared numbers is preserved, the state of the device after the threshold is reached is increased reliability

This signal does not change. After that, the carrier is shifted to the end of the line and the number of the adder 26 becomes less than the number of the register P. In this case, the comparison block 9 generates a signal that opens the element AND 5. The pulse pulse of the element 20 And through the element 5 is fed to the element 18.. The output of element 18 is formed by a negative impulse, on the leading edge of which the trigger 23 is set to one state.

The trigger 23 as the trigger 24 operates in the counting mode. The trigger 23 closes the elements 19 and 20, sends signals to the perforant containing a low level to the mode setting input of the memory block 16, sets the information recording mode and opens the elements 2 and 23, the outputs of which also form two sequences of clock pulses. similar to the pulse sequences of elements 19 and 20. The 1M pulse of element 2 is fed to the gate input of memory block 16 and the line code from register 11 is written to it at the address specified by counter 17. After this, the pulse from the input of the element 22 increases the address counter 17 by one, through the element 15 is zeroed registers P - 13, through the element 10. The trigger element 2, and by member 18 - 23. Last disables trigger elements 21 and 22 and again includes operation members 19 and 20.

Since under the photodetectors of block 14 there is a lower boundary of the line and the carrier is shifted to the separation area between adjacent lines

information, the sum of the unit bits Q i of the comparator and the information at the output of the adder 26 is reduced to the inputs of the second register, and the inputs are zero. In this case, after zeroing of the threshold element 2, element 5 is closed and prepared for opening through the element NO 8, element 7. The clock pulse of the element of the comparison unit, the third input

the comparison unit is connected to the first input of the third element And and to the second

with the outputs of the third register and with ing the formation inputs of the first register, the outputs of the second register are connected to the corresponding inputs of the second

that 20 through the elements 7 and 6 periodically rewrites the current numbers of the adder 26 in the register 12 and code) I Strohodom fourth element And the inputs

ki from register 13 to register .11. Therefore, when there will be a dividing section of the line under the photo-detectors1, zero registers are recorded in registers 11–13. In this state, the device is ready to process the next line of the storage medium. Thus, in a device for reading out information from a mobile carrier due to optimization of the moment of fixing information of a line read from a mobile carrier, and a minimum time for polling the code bits of the information line. The moment of fixing the information is determined with a stable value of the code of the string within a threshold number of cycles.

Claims (1)

The invention of the device for reading information consequently, the combined blocks of photodetectors and amplifiers, a pulse generator, four AND elements, an OR element, three registers, a counter, a first trigger, a memory block, and an NOT element,. the output of which is connected to the first input of the first element I, the first and second outputs of the comparison unit are connected respectively to the first inputs of the first and second elements I, the outputs of the first register are connected to the inputs of the first group of the comparison unit, the outputs of the second register are connected to the information inputs of the memory block, outputs which are informational outputs of the device, that is, because, in order to make sure that the information is read correctly, the threshold element, the second element of the NTO, fifth, sixth, second the eighth and eighth elements are And, the second trigger, the first and second elements of the IL-NAND and the adder, the outputs of which are connected to the inputs of the second group 0 i of the comparison block and the information inputs of the second register, and the inputs are the groups of the comparison block, the third input with the outputs of the third register and with ing the formation inputs of the first register, the outputs of the second register are connected to the corresponding inputs of the second the input of the fourth element And the inputs the threshold element is connected respectively to the outputs of the first elements AND and OR, and the output to the second input of the third element AND and to the input of the element NOT; the output of the second element AND is connected to the first inputs of the first elements OR and IPI NOT, the second inputs of which are connected to the output of the fourth element AND, the output of the third element AND is connected to the first input of the second element OR NOT, the output of the second element OR is connected to the inputs The reset of the first, second and third registers and the second input of the first element OR, the inputs of the reset of the first trigger and the counter are connected to the first input of the OR element and are the input of the initial setup of the device, the output of the fifth element AND is connected to the synchronizing input of the third register, the output of the pulse generator connected to the first inputs of the fifth, sixth, seventh and eighth elements; Com and And with a sync input. : the second trigger, the inverse output I of the first trigger is combined with the information input and connected with the second Yy U JfgT i; S -3nS ..... JMb .. lUieiii JiiLLj I T k the inputs of the fifth and sixth elements And with the input control the operation mode of the memory unit, and the direct output is connected to the second inputs of the seventh and eighth elements And, the direct output of the second trigger is connected to the third inputs of the fifth and seventh elements And,. the inverse output is combined with the information input and connected to the third inputs of the sixth and eighth elements And, the output of the sixth element And connected to the second inputs of the first and second elements And, and to the third inputs of the third and fourth elements And, the output of the seventh element And connected to The strobe input of the memory block, the output of the eighth element I is connected to the counting input of the counter and the second inputs of the second elements OR and OR, the outputs of the counter are connected to the address inputs of the memory block, the output of the first element OR is NOT connected to the synchronization inputs of the first and the second register, the output of the second. e kent OR-NOT is connected to the synchronized input of the first trigger.