SU1698883A1 - Data input device - Google Patents

Abstract

The invention relates to automation and computing and can be used in input devices. The purpose of the invention is to increase the reliability of the input information by eliminating faulty information in the process of operating the device. For this, an information input device comprising a pulse generator 1, a differentiating chain 2, a keyboard 3 containing capacitive dividers consisting of a variable capacitor 4, a button and a fixed capacitor 5, and emitter repeaters b, a multiplexer 9, a first counter 11 and trigger 12; keys 7, decoder 8, first and second elements 13 and 14, delay element 15, element 16, element 18, NOT 18, second counter 19, and two threshold element 20 are inserted. The device allows decoupling between capacitive dividers keyboard 3 using the input keys 7 and the decoder 8, as well as protection against the effects of various kinds of impulse noise, which eliminates the appearance of wallpaper information and increases the reliability of the input information. 2 Il. (L С о о 00 00 00 СО L

Description

The invention relates to automation and computing and can be used in input devices.

The purpose of the invention is to increase the reliability of the input information.

FIG. 1 shows a functional diagram of the proposed device; in fig. 2 - timing charts of the device.

The information input device comprises a pulse generator 1, a differentiating chain 2, a keyboard 3 including capacitive dividers from a variable capacitor 4, buttons and a fixed capacitor 5 and emitter repeaters 6, keys 7, a decoder 8, a multiplexer 9, information outputs

10 devices, first counter 11. trigger 12, first 13 and second 14 elements AND, delay element 15, element OR 16, strobing the device output 17, element NOT

18, the second counter 19 and the two-threshold element 20. The output of the pulse generator 1 through the differentiating chain 2 is connected to the information inputs of the keys 7, the other inputs of which are connected to the common bus, and the outputs to the inputs of the keyboard 3. The outputs of the variable capacitors 4 are the inputs of the keyboard 3 The pins of the permanent capacitors 5 are connected to the common bus, and the outputs of the capacitive dividers to the inputs of the emitter repeaters b, the outputs of which are the outputs of the keyboard 3, the outputs of the keyboard 3 are connected to the information inputs of the multiplex Ekora 9, the output of which is connected to the input of the two-threshold element 20. The output of the pulse generator 1 is connected to the first counter of the first counter 11 and the first inputs of the first 13 and second 14 elements And, and the outputs of the first counter

11 are connected to the address inputs of the multiplexer 9 and the decoder 8, the outputs of which are connected to the control inputs of the keys 7. The second input of the first element AND 13 through the delay element 15 is connected to the output of the OR element 16, the first input of which is connected to the output of the second counter

19, the counting input of the counter 19 is connected to the output of the second element I 14, the second input of which is connected to the output of the trigger 12 and to the control input of the first counter 11. The first output of the two threshold element 20 is connected to the second input of the element OR 16 and through the element 18 to the first input of the installation in About the trigger 12, the first input of the installation in 1 of which is connected to the second output of the two-threshold element

20, and the second inputs of the installation in 1 and O

trigger 12 is connected to the output of the first element And 13.

The information input device operates as follows.

The pulse signal from the pulse generator 1 (Fig. 2a) is fed to the counting input of the first counter 11 and simultaneously via the differentiating chain (Fig. 26) to the information inputs of the keys 7, Signal c

0 outputs of the first counter 11 are fed to the address inputs of the decoder 8, which performs key management 7, which allows alternately connecting the output of the differentiating chain 2 to the inputs

5 keyboards 3. with the non-connected inputs of the keyboard 3 closed on a common bus. This allows realizing isolation between capacitive dividers and realizing the full discharge of residual voltages from capacitors 4 and 5 of capacitive dividers. Consequently, the signal at the output of multiplexer 9 is determined only by the information component of the input pulse coming from one emitter repeater 6. This signal from multiplexer 9 is then fed to the input of two threshold element 20. Threshold element 20 evaluates the incoming signal by comparing with predetermined threshold values mi and

0 extends them along the outputs (Fig. 2c, d and e).

The generated pulse at the first output of the two-threshold element 20 (Fig. 2d) through the element NOT 18 enters the first

5 input installation in On the trigger 12 and at the same time through the element OR 16, the element 15 of the delay and the first element And 13 generates a clock pulse that arrives simultaneously to the second inputs of the installation in 1 and O

0 trigger 12 (Fig. 2e, g and h). The generated pulse at the second output of the two-threshold element 20 (FIG. 2d) is fed to the pitch input of the installation in 1 flip-flop 12, which is set to state G.

5 In the initial state, when no button of the keyboard 3 is pressed, the trigger 12 is in the state O and the first counter 11 generates a sequence of addresses according to which the multiplexer 9 searches for the keyboard 3, and the decoder 8 has the corresponding connection of capacitive dividers. In this case, the signal at the outputs of the two-threshold element 20 is zero. When you press a button on the keyboard 3

5, the signal at the output of the multiplexer 9 (Fig. 2c) begins to grow, and when going through the first voltage threshold, the two-threshold element 20 at its outputs, respectively, contains the levels of G and O (Fig. 2d and e). Meanwhile, the trigger 12 maintains its state. When the signal passes through the second voltage threshold, the second output of the two-threshold element 20 appears level 1 (Fig. 2e) and the trigger 12 synchronizes (Fig. 2h) to state 1 (Fig. 2i). In this case, the first counter 11 is blocked and the keyboard 3 is polled to the address where the first counter 11 is locked, as long as the keyboard button 3 is pressed. The code at the output 10 of the device, i.e. at the outputs of the first counter 11, if there is a signal at the output 17 of the device, i.e. 1 at the output of the trigger 12, is the output signal of the device, namely, the code of the pressed button of the keyboard 3.

The signal 1 of the trigger 12 opens the second element I 14 through the second input and through it the first input passes pulses from the pulse generator 1 to the counting input of the second counter 19 (Fig. 2k), at the output of which over time signals overflow signals appear Fig. 2l).

When the keypad 3 button is pressed, the level of the signal coming from multiplexer 9 decreases, and when it goes over the second voltage threshold in the two-threshold element 20, its outputs respectively have levels 1 and 0. The trigger status 12 does not change. With a further decrease in the signal level from multiplexer 9 and passing it through the first voltage threshold in a two-threshold element 20 (Fig. 2c), the O level appears at its first output. The sync pulse generated by the overflow signal by the second counter 19 sets the trigger 12 to Oh, i.e. in the original. When this is done, the first counter 11 is released and the keyboard 3 is polled.

The presence of a device's dead zone based on the input signal, determined by the potential difference between the first and second voltage thresholds of the two-threshold element 20, provides protection from the operator's finger twitching when the button is pressed and released. .

The invention allows decoupling between capacitive dividers of the keyboard 3 using the input keys 7 and the decoder 8, as well as protection against the effects of various kinds of impulse noise, realized by entering information into

a certain sequence using the introduction of two elements AND 13 and 14, a delay element 15, an element OR 16, an element NOT, a second counter 19 and a two-threshold element 20, which eliminates the appearance of erroneous information and thereby increases the reliability of the entered information.

Claims (1)

Invention Formula An information input device comprising a pulse generator, a keyboard, a multiplexer, a differentiating chain, a first counter, a trigger whose output is connected to the control input of the first counter and is a gate output of the device, the output of the pulse generator is connected to the input of the differentiating chain and the counting input of the first the counter whose outputs are connected to the address inputs of the multiplexer and are information outputs of the device, the keyboard outputs are connected to the information inputs of the multiplexer, which are different in that, in order to increase the reliability of the input information, a decoder, keys, or two threshold , the element is NOT, the delay element, the first and second elements are AND, the second counter, the output of which is connected to the first input of the OR element, the first output of the two-threshold element is connected to the second input by NTA OR and NOT through the element with the first input of the O flip-flop setup, the first inputs of the first and second elements I are connected to the output of the pulse generator, the output of the second element I to the counting input of the second counter, the output of the trigger to the second input of the second element I, the outputs of the first counter to the inputs of the decoder, the outputs of which connected to the control inputs of the keys, information. the input inputs of which are connected to the output of the differentiating chain, the outputs of the keys are connected to the inputs of the keyboard, the output of the multiplexer is connected to the input of a two-threshold element, the second output of which is connected to the first input of the installation in 1 trigger, the second inputs of the installation in 1 and in O of the trigger are connected to the output of the first element AND, the second input of which is connected to the output of the OR element through a delay element.