SU1388846A2 - Device for comparing codes - Google Patents

Description

(61) 1229751

(21) 4147567 / 24-24

(22) 10/02/86

(46) 04/15/88. BULL. № 14 (72) N.V.ROSIP and A.P. Smirnov

(53) 681.325.5 (088.8)

(56) USSR Author's Certificate No. 1229751, cl. G 06 F 7/04, 1984.

(54) DEVICE TO COMPARE CODES,

(57) The invention relates to automation and computing, can be used in the technical means of control of discrete systems and is an improvement of the device according to the author. St. USSR No. 1229751. The purpose of the invention is to increase the speed of the device by reducing the time of analysis of two code sequences in the presence of at least one pair of unequal codes. The device for comparing codes contains a comparison circuit 7, elements AND 1-4, a generator

8 pulses, counter 9 modulo two, triggers 5.6, the counter recording enable input connected to the inverse output of the second trigger, and its information inputs to the input of the logical unit of the device. In the device at the time when the first pair of unequal codes is present at the inputs of the device, at the output of the comparison circuit a signal of the level of logical unit is generated, which allows the clock pulse to pass through the third AND element to the fault input of the second trigger. The signal from the inverse output of the second trigger records the code of all units in the counter, which leads to the formation of an overflow signal for the counter, which passes through the open fourth And element and generates an inequality signal at the output of the device. 1 il.

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The invention relates to automation and computer engineering and can be used in technical means for controlling discrete systems.

The purpose of the invention is to increase the speed of the device by reducing the time of the angularization of code sequences with ngschy at least one pair of unequal codes.

The drawing shows a diagram of the proposed device for comparing codes.

The device contains AND 1-4 elements, triggers 5 and 6, a comparison circuit 7 (for example, a 1X 134SP1 or 533SP1 chip with an inverter on the output), a generator of 8 pulses, a counter 9 modulo P, a trigger input 10, inputs 11 and 12 of the compared codes, outputs 13 and 14, input 15 logical units.

The device works as follows.

The input 10 of the device start-up receives a signal that sets the riggers 5 and 6 to one state and the counter to zero. The signal from the direct output of the trigger 5 permits the passage of pulses from the generator 8 through the element I2 to the counting input of the count Chick 9 and the first input of the element IZ. The frequency of the pulses of the generator 8 coincides with the frequency of changing codes of code sequences at the inputs 11 and 12 of the device. In case of equality of the incoming codes, the comparison circuit 7 generates a potential low-level signal, which blocks the IZ element at the second input, and a pulse one: the signal from the output of the I2 element does not reset the trigger. With the inequality of codes at the inputs 11 and 12 devices. comparison circuit 7 generates a potential high level signal, which opens an IZ element at the second input, which allows the pulse from the output of the I2 element through the IZ element to reset trigger 6 to the zero state, on the inverse output of which

a write signal to counter 9 of the code of all units is generated. The pulses from the output of the element I2 arrive at the counting input of the counter 9 modulo P.

Thus, when each equal pair of codes of two compared sequences arrives at the inputs 11 and 12 of the device, the contents of counter 9 are increased by one. Upon receipt of the U-th code pair in the counter 9, an overflow signal is generated, which resets the trigger 5, the locking signal from the direct output element I2, and which goes to the second inputs of the I1 and 4 elements. Since all the P pairs of codes of the two sequences were equal , the trigger 6 was not reset, therefore the overflow signal of the counter 9 through the open signal from the direct output of the trigger 6 element I1 is fed to the output 13 of the device, i.e. a sequence equality signal is generated.

If any pair of codes of the compared sequences is inequality, the code of all units, i.e. an overflow signal is formed immediately, and since the trigger 6 is activated, the element I4 is opened and the inequality signal of the two sequences is generated at the output 14 of the device.

Claims (1)

35 claims Device for comparing codes according to auth. No. 1229751, characterized in that, in order to increase speed by reducing the time of analyzing code sequences in the presence of at least one pair of unequal codes, the inverse output of the second trigger is connected to the record resolution enable input of the counter modulo n, the information inputs of which are connected to the input of the logical unit devices.