SU1267401A1 - Information input device - Google Patents

Abstract

The invention relates to automation and computing and can be used to enter information from a keyboard. The aim of the invention is to improve the reliability of the device. The device contains a keyboard, the first and second elements 1 SHI, the first and second one-shot, from the first to the third triggers, from the first to the sixth elements AND and the element NOT. The goal is achieved by introducing into the known device two single vibrators, the OR element and new connections, allows the device to fully protect the bounce effect of the switching elements both when they are pressed and released, and to reliably hold the device in its initial state before switching the switching an item. 1 il. (L

Description

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The invention relates to automation and computing and is intended to enter information from a keyboard.

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

The drawing shows a functional diagram of the device.

The device contains a keyboard 1, which includes the first and second groups of isolating elements 2 and 3, the switch 4 and the encoder 5 the first element OR 6, the second element ШШ 7, the element 8, the first 9, the second 10 and the third 11 the triggers, the first 12, the second 13, the third 14, the fourth 15, the fifth 16, the sixth 17 elements And, the first 18 and the second 19 one-vibrators Positions 20-24 denote the inputs and outputs of the device.

In the initial state, all switching elements of the keyboard 1 are open, triggers 9-11 are in the initial zero state. An end-to-end pulse transfer circuit is formed from input 20 through element 15 to output 21, the inputs of decoupling elements 2 and 3, the first and second switch 4, and the first inputs of the sixth and fifth elements AND are respectively high (1) and low (O). the potentials from the inverse and direct outputs of the trigger 11. On the horizontal keyboard buses 1 and on the first information inputs of the switch, 4 there are low potentials, and on the vertical keyboard bus and the second information buses of the switch 4 there are high potentials, i.e. at the outputs of co1 ' 1 switch 4, there is zero information arriving at the inputs of the encoder 5 and the inputs of the OR circuit. The low potential from the output of the SHSh 6 edement enters the reset inputs of trigger 11 and trigger 9 (via I1Sh 7).

The device works as follows.

When the switching element of the keyboard 1 is closed, the corresponding element of the keyboard 1 will be sampled from the horizontal busbars and at the corresponding output of the switch 4 the potential will switch to O to 1. The first one-shot vibrator will work from the first impulse during bounce the first trigger will go ot67401 .2

a solid impulse of duration 1 (where there is more bounce time), on the falling front of which trigger 9 will trigger, and on the information input

5, the signal will come directly from the output of the element OR 6. Therefore, the first trigger will be set to one at the time t + t ((t is the time at which the switching element is pressed), i.e. when information outputs 24 receive reliable information In the pause between the sync pulses through the AND 12 element, the trigger 5 will be set to one state, which enables the operation of the AND 14 element and blocks the I 15 element. d elements 16 and 17. At output 22 of element 17, the first pulse of the sync signal is clock signal (clock signal) for the binary information code located at information outputs 24. At the end of the first synchronization pulse, trigger 11 changes its state (from the original zero will be set to one) and

30, the vertical busbars of the keyboard 1 will be sampled at the outputs of the switch 4, and at the information outputs 24 a binary information code will be generated HoBbDi. After the clock pause at the output of the element AND 16 - the second output exit 23 - the second pulse of the synchronization sequence is received, which, like the first pulse), is a clock (gate) signal for the binary signal. of the code present on the information ","

24 outputs. At the end of the second sync pulse, the second single vibrator is triggered on the falling edge, the output of which produces a pulse of duration t

(Where

approximately equal to the duration of the sync pulse), which sets the trigger 11 to the initial zero state through the element OR 7, blocking the element 12 and the element 13 under the control. After the second sync pulse has expired, the trigger 11 also returns to the initial zero state. Pause sync happens

Claims (1)

5 installation of the trigger 10 to the initial zero state and the third and subsequent pulses of the sync signal in TC at the output 21 as the 3 synchronizing signal, which differs from the input (input 20) by the absence of only two pulses that went to the first 22 and second 23 clock outputs of the device. When the switching element of the keyboard 1 is opened at the output of the first element OR 6, a series of impulses from the bounce of the contacts occurs. On the positive front from the first pulse, the first single-shot 18 operates, from the output of which a pulse with a duration arrives at the synchronization input of the first trigger 9. Because during time i, low potentials are established at the outputs of switch 4, at the output of the first element OR 6 and at the information input The first trigger 9 will also set a low potential, with the result that the first trigger will remain in its original zero state. In the case when there is no contact bounce when the switching element of the keyboard 1 is opened, the first one vibrator will not work. Consequently, the first trigger will remain in its original zero state. Therefore, when opening the switching element; The device is set to ready for operation. Apparatus for inputting information comprising a keyboard, the first element OR, the first, second and third triggers, the element NOT from the first to the sixth elements AND, the outputs of the first keyboard group are information outputs of the device, the output of the second keyboard group is connected to the inputs of the first element OR, the second inputs of the first and second elements AND are connected to the output of the NOT element, the input of which and the first inputs of Tr 014 of the first and second elements of AND are the device synchronization input, the outputs of the first and second elements in AND are connected respectively to the installation and reset inputs of the second trigger, the direct and inverse outputs of which are connected to the second inputs of the third and fourth elements AND, respectively, the output of the fourth element I is the output of the device clock, the output of the third element I is connected to the synchronization input of the third the trigger and the second inputs of the fifth and sixth elements And, the inverse output of the third trigger is connected to the first input of the keyboard and the first input of the sixth element And, the direct output of the third trigger is connected to the second input of the keyboard, the first input of the fifth element I, whose output is the second clock output of the device, the output of the sixth element I. is the first clock output of the device, the forward and inverse outputs of the first trigger are connected to the first inputs of the first and second elements And, respectively characterized in that, in order to increase the reliability of the device, the first and second single vibrators are introduced into it, the second OR element, the output of which is connected to the reset input of the first trigger, the output of the first SRI element is connected to the input of the first one-shot, the second input of the second element OR, the reset input of the third trigger and the information input of the first trigger; the output of the first one-vibration is connected to the synchronization input of the first trigger; the input of the second one-oscillator is connected to the output of the fifth element I, and the output to the first input of the second element OR.