SU1472894A1 - Data input device - Google Patents

Abstract

The invention relates to automation and computing and can be used to organize manual entry of information into control or computing systems. The aim of the invention is to increase reliability when entering repeated symbols. The device contains a generator of 1 pulses, a multiplexer 2, a block of 3 switching elements, counters 4,6, shaper 5 pulses, triggers 7,8, elements And 9,10. The device makes it possible to distinguish between single and repeated pressing of the same key, since each time it is touched, a "flag" signal is formed and the trigger 7 is transferred to a single state, the return of which is carried out only when the information is read by an external device and when the pushed pad is released. Therefore, the subsequent generation of the "Flag" signal is performed after the arrival of the "Reset" signal only when the operator releases and then presses the key. Due to the fact that each time you touch a key, a "flag" is set in the device, and when the information is read, it is reset, the keypad is locked in the device by simultaneously pressing two or more keys, because the "flag" setting, which means that reading the code corresponding to pressing the next pads occurs only after the previous one is released. 1 il.

Description

The invention relates to automation and computing and can be used to organize manual entry of information into control or computing systems.

The aim of the invention is to increase the reliability of the device when repeating characters.

The drawing shows a block diagram of the device.

The device contains a generator 1 pulses 9 multiplexer 2, block 3 switching elements, the first counter 4, shaper 5 pulses, the second counter 6, the first

7 and

and the second 8 triggers, the first 9 second 10 elements. And.

The information input device operates as follows.

In the absence of contact between the contact area of the block 3 of the switching elements, the inverting output of the trigger 7 is present 1 and the pulses from the generator 1 through the element 9 are summed by the first counter 4. The output codes of the counter 4 are sent to the address inputs of the multiplexer 2e which connects the contact pads to the shaper 5 pulses. From the output of the generator 1, the pulses go to the second counter 6, from the output of which, with each overflow, the signal sets the trigger 7 to the zero state (1 at the inverting output) „

When one of the contact pads of the block 3 of the switching elements touches the multiplexer 2, which performs the alternate interrogation, connects the corresponding pad to the input of the driver 5 pulses. Under the action of an alternating voltage induced in the operator's body, the formative body 5, for which the amplifier-limiter can be used, forms rectangular pulses with a frequency of 50 Hz. The counter 6 is then set to the zero state every 20 ms. The frequency of the generator 1 and the coefficient of recalculation of the counter 6 are chosen in such a way that the overflow of the counter 6 occurs in a time longer than the transients caused by bounce. Therefore, during the touch of a key, the pulses arising from the overflow of counter 6 are absent

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five

0

five

0

five

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five

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vuat. After the contact, the first pulse from the output of the imaging unit 5 is fed to the input of the element And 10, at the second input of which there is a level 1 from the trigger 7. At the same time, a single impulse is formed at the output of the element And 10, which sets the trigger 8 into the single state. At the inverting output of the trigger 7, the O level appears, which prohibits the further arrival of the pulses of the generator 1 to the input of the counter 4. The multiplexer 2 stops at the position when the contact pad, pressed by the operator, is connected to the input of the pulse shaper 5. At the information output of the device, there is a code corresponding to the pressed key, and on the control key there is a signal that the device is ready for outputting information (Flag).

After the information is read by the device that processes it, a Reset pulse is generated. The trigger 8 is reset and the flag is set to the zero state.

When you release the key from the imager 5 pulses to the input of the installation in the O counter 6 pulses do not arrive. A counter 6 sums the pulses arriving from the generator 13, and when it overflows, a pulse of setting the trigger 7 to the zero state is formed. The latter is set to O and permits the passage of pulses to the input of counter 4, which controls multiplexer 2. Multiplexer 2 connects alternately to the input of the driver 5 pulses of the contact pads of block 3 of switching elements.

Gating multiplexer 2 with generator 1 pulses or using a two-input driver 5 allows the device to work not only on the principle of using an alternating voltage induced in the operator's body, but also on the basis of other principles, for example, using the effect of connecting the capacitance of a body, operator or external a low-voltage source (e.g., a source used to power the chips) to the input of multiplexer 2 via the resistance of the skin of the operator’s finger.

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When an alternating voltage induced in the operator's body is used in the device, the formation of rectangular impulses of the installation of the counter 6 in O is accomplished by strengthening the alternating voltage induced in the operator's body by the driver 5, which can be used as a limiting amplifier.

If a constant voltage is connected to the input of the multiplexer 2 through the skin of the operator's finger, the input of the imaging unit 5 (when the multiplexer 2 is connected to the corresponding pad) receives a constant signal. In this case, to form rectangular pulses at the output of the former 5, which, as in the previous case, can be implemented as an amplifier - limiter, it is necessary and sufficient to introduce a connection connecting the second output of the generator 1 to the building (enabling) input multiplexer 2. Then, a constant voltage is applied to the input of the imaging unit 5 periodically with the frequency of the generator 1 and at the output of the unit 5, the contact square of the counter 6 in the generator left state.

In order for the device to use the effect of connecting the capacity of an operator’s body, it is necessary to introduce two additional links. In this case, a two-input driver described in the prototype can be used as a driver 5. In this case, at the output of the driver 5, the operator’s contact area (connecting the body capacitance) to the generator 1 frequency also appears zero state. The duration of the pulses is determined by the capacity of the operator’s body.

The principle of using an alternating voltage induced in the operator's body is advisable to use in devices with network power. The application of the principle of connecting an external source to the multiplexer input through the resistance of the skin of the operator’s finger allows the use of the device728944

Operation in battery-operated portable devices operating in the field. When the device is operated from the mains supply, the actuation of the imaging unit 5 occurs not only from connecting the source through the skin of the operator’s finger, but also from

10 belt voltage, which increases the reliability of the device for entering information.

Using the effect of connecting the capacity of the operator’s body allows

15 to ensure the ability of the device to operate when powered from the network, and offline.

Thus, the proposed device makes it possible to distinguish between one and multiple times and repeatedly pressing the same key, since each time it is touched, the Flag signal is formed and the trigger 7 is transferred to the single state, which is returned only when the external device reads the information and when you release the pads. Therefore, the subsequent formation of the signal Flag is carried out

30 after the arrival of the signal Reset only when released and then pressed by the operator. Due to the fact that every time you touch a key in a device for entering information, the Flag is set, and when reading information, it is reset, the device locks the keyboard by simultaneously pressing two or more keys, since the Flag setting, and hence the ability to read the code corresponding to pressing the next pad, occurs only after the previous one is released. Recruitment

The corresponding recalculation coefficient of the counter 6 and the frequency of the pulse generator 1 protects the device from transients when the key is pressed and released. In the Q device, you can use different principles of the sensor.

Claims (1)

Invention Formula A device for entering information containing a block of switching elements, a multiplexer, two triggers, a pulse generator, the first element 5 14728946 Both the first counter, the outputs of which are second, the second element And and the second are connected to the address inputs of the multi, the overflow output of which is a coaxial multiplexer and is informational with the reset input of the first trigg output of the device, the outputs of the block –ger, the output of the multiplexer are connected switching elements are connected to the input of the pulse generator, with information inputs the multi-output of which is connected to the input the plexer, the output of the pulse generator reset the second counter and the first connected to the first input of the first Ele input of the second element And the output ment And, the output of which is connected by its which is connected to the input by the input of the first counter, the output of the first trigger of the second trigger, the output of which the first trigger is connected to the second input-connected to the installation input of the first the house of the first element And, the output of the second trigger, clock input of the second The first trigger is the control of the you-counter connected to the output by the device generator, the distinguishing feature of the pulse torus, the second input of the second, Now that, for the purpose of the I-element, it is connected to the output of the device’s first reliability level at the first trigger, the reset input of the second de repeating characters, the trigger device is a control input The structure contains a pulse device driver.