SU1401594A1 - Touchless keyboard - Google Patents

Abstract

The invention can be used in input and output devices. The purpose of the invention is to expand the scope. The touch keyboard contains a multiplexer with touch pads 2, a counter 3, a memory register 5 and a single-vibrator 8 with a restart. The introduction of the one-shot 7 with restarting and the formation of new functional connections increases the number of sensory pads 2 and increases the reliability of the keyboard by reducing the requirements for the duration of the triggered pulses. 1 il.

Description

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The invention relates to a pulse technique and can be used in input and output devices.

The aim of the invention is to expand the field of application due to the possibility of increasing the number of touch pads and increasing reliability by reducing the requirements for the duration of the clock pulses.

The drawing shows the functional diagram of the touch keyboard.

The touch keyboard contains a multiplexer 1, the information inputs of which are connected to ceHcopHbiN; H pads 2, the address inputs are connected to the outputs of counter 3, and the synchronization input is connected to clocking bus 4 and to the input of counter 3, a memory register 5 whose inputs are connected to the corresponding outputs counter 3, and the outputs are connected to the address outputs 6 of the device; the output by the multiplex operator does not have time to charge to the necessary threshold value in the time determined by the duration of the clock pulse. In this case, the next trigger pulse will enter the input of the second one of the vibrator 7 at a time equal to 2T, and it will recover, and then start up again and will be in the active state until the next Hg. The process is repeated continuously while the operator is touching one of

10 sensor pads 2. As a result, pulses with a period of NT are generated at the output of the second one-shot 7, where N is the number of touch-screen areas 2. The first pulse starts the first one-shot 8, so. same working in rerun mode. At the output of the first one-shot 8, an impulse is generated, on the front of which a register 3 is recorded in register 5. At address outputs 6 a binary code of the decimal number k + 1 is generated.

pa I is connected to information input 20 where k is the sequence number of that of the sensory second one-oscillator 7 with repeated sites 2, to which it touched the operation trigger, the output of which is connected to the input resistor. On the enable bus 9, a first one-shot 8 is formed with a repeated signal for tracking the output address code, the output of which is connected to the inputs 6. The duration of a first write pulse of register 5 and to the resolution output is--; One single vibrator 8 (ty ,.) is set to be large. a ggt.1 ..

NOW tire 9.

The touch keyboard works as follows.

After switching on the supply voltage, the operator does not touch the touch pads 2.

neck than the NT, as well as longer than the duration of the transition process the operator touches the touch pad 2. The first one-shot 8 will recover, and the touch keyboard will prepare to form

From clocking bus 4 to sync- 30 next code, if the operator releases

The first input of multiplexer 1 and the input of counter 3 receive short pulses with a follow-up period T. Counter 3 switches along the negative edges of these pulses and scans the touch plane pads 2 or if the frequency of contact with them becomes less than l / Crii.

Claims (3)

Invention Form Touch keyboard comprising touch pads, multiplexer, touch bus 2. Since the initial capacity is 35, the meter, the first one-shot with From the free touch pads 2, time to charge to the required threshold for the time determined by the duration of the clock pulses, even shorter pulses with a follow-up period T are continuously generated at the output of the multiplexer 1. These pulses start and hold active state, the second one-shot 7, operating in the restart mode, the duration of one pulse of which (fVn) satisfies the ratio, T. The first one-shot 8 is in the initial state — recording and The information in register 5 is blocked, the state of the output b is unchanged, the tracking signal on the enable bus 9 is absent. If the operator touched one of the touch pads 2, then in the time interval of her choice () the output of the multiplexer 1 did not generate a pulse, since the capacity of this touch pad increased by the amount of additional capacity introduced the operator does not have time to charge to the required threshold for the time determined by the duration of the clock pulse. In this case, the next trigger pulse will enter the input of the second one-shot 7 after a time equal to 2T, and it will recover, and then start up again and will be in the active state until the next Hg. The process is repeated continuously while the operator is touching one of sensor pads 2. As a result, pulses with a period of NT are formed at the output of the second one-shot 7, where N is the number of touch-areas 2. The first pulse starts the first one-shot 8, also operating in the restart mode. At the output of the first one-shot 8, an impulse is formed, on the front of which the state of the counter is recorded in register 5 3. At the address outputs 6, a binary code of a decimal number k + 1 is generated.  a ggt.1 .. neck than the NT, as well as longer than the duration of the transition process the operator touches the touch pad 2. The first one-shot 8 will recover, and the touch keyboard will prepare to form the following code if the operator releases touch pads 2 or if the frequency of touching them becomes less than l / Crii. Invention formula Touch keyboard comprising touch pads, multiplexer, bus so0 five 0 five by restarting and registering the memory, the touch pads are connected to the corresponding information inputs of the multiplexer, the address inputs of which are connected to the corresponding outputs of the counter and the corresponding inputs of the memory register, the clock bus is connected to the synchronization input of the multiplexer, the output of the first one-vibrator is connected to the output of the device and the synchronization input of the register, the outputs of which are connected to the address outputs of the device, characterized in that, in order to expand the scope of And due to the possibility of increasing the number of touch pads and increasing reliability by reducing the requirements for the duration of the clock pulse, a second one-shot one-shot with a restart is entered into it, the information input of which is connected to the output of the multiplexer, the output is connected to the input of the first one-shot and the counter clocking