SU1456943A1 - Information input device - Google Patents

Abstract

The invention relates to computing and is intended to manually enter information into a computer using a keyboard. The aim of the invention is to improve the reliability of the device. The device contains a keyboard, a descrambler, a multiplexer, two triggers, a counter, two one-oscillators, an AND-NO element, an OR-NOT element, a clock input, a code reading input, an information output and an output. readiness. By introducing a second one-shot, the element OR-NOT and the new links, false positives are eliminated. 2 Il.

Description

one

The invention relates to computing and can be used in devices for manual entry of information into computers, in terminal stations and information-measuring systems for various purposes.

The aim of the invention is to increase the reliability of the information input device.

In Fig.1, the functional representation is presented. . a diagram of a device for inputting information into a computer; figure 2 - the timing diagram of his work.

The information input device comprises a keyboard 1 consisting of switching elements connected at the intersection of the input vertical and output horizontal conductors. Switching elements are organized in a matrix. The device contains .. .. there is also a decoder 2, multiplexer 3, triggers 4 and 5, counter 6, one-shot 7 and 8, elements AND-NOT, 9 to OR-NOT 10, the device has a clock input VI, input 12 reading the code, information output 13 and output 14 readiness.

The device works as follows.

In the initial state, when the keys are not pressed, there are high potentials at the keyboard outputs, triggers 4 and 3 are in the zero state, the output of the NAND 9 element is zero potential, the ORID 10 element transmits clock pulses to the counting input of the counter 6, which scans the switching elements of the 1 st keyboard 1 by searching the codes at the inputs of the decoder 2 and the multiplexer 3. At the same time, a low level at the output is active

decoder 2, When you press any key on keyboard I, the low level of the corresponding output of decoder 2 goes to the corresponding input of multiplexer 3, Output number of decoder 2 and input number of multiplexer 3 determines the position of the key in the matrix, the difference from O to output multiplexer. 3 causes the trigger 4 to be set to one, which, in turn, triggers the one-shot 7, the dwell time of the one-shot 7 and 8 is determined by the time it takes to calm the bounce of the switching element. For the duration of the pulse generated by the single vibrator 7, the trigger 4 is kept in one state regardless of the change of information on its D input. Setting the trigger 4 to 1 causes the trigger to switch 5 into 1 and prohibits the arrival of clock pulses through the OR-NOT. 6, The establishment of a 5 in 1 trigger causes an IS-HE element 9 to generate a ready signal at output 14, which indicates to the computer that data is available at output 13. On a ready signal, the computer sets a read signal for the code at input 12, which supports the signal It is ready and blocks the count in counter 6 until the data from output 13 is read, after which the read signal is removed. In addition, the reading signal trigger 5 is set to O,

Releasing the key causes a drop from 1 to O at the output of the multi-l plexer 3, which sets the trigger 4 on the next clock pulse to the zero state, which is maintained by the one-vibrator 8 until the bounce in the switching element occurs, the flip of the trigger 5 to the zero state in the absence of a signal reading input 12 (high level) causes a ready signal to be reset at output 14 and the continuation of the count in counter 6,

Pressing two keys at once results in outputting the code of the key to the output 13, which is pressed first, as the trigger 4 sets the signal at the output of the multiplexer 3 immediately. Strictly simultaneously pressed, the key of the key having a lower code value is issued. When you release the first key, The pressed second code of the second key is output on output 13 after resetting the read signal for the first key.

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A device for entering information into a computer that contains a keyboard, a decoder, a multiplexer, a counter, two triggers, a first one-shot and an NAND element, the decoder outputs are connected to keyboard inputs, the outputs of which are connected to information inputs of a multiplexer, whose address inputs are connected to the lower outputs the bits of the counter, the outputs of the higher bits of which are connected to the inputs of the decoder, the output of the multiplexer is connected to the D-input of the first trigger, the clock input of which is connected to the device's clock input, input installation in O of the second trigger is connected to the input of the readout of the device code, the D input of the second trigger is connected to the bus of the unit potential of the device, the output of the digits of the scale is connected to the information output of the device, which is

35 in order to improve reliability, the second one-shot and the element OR-NOT are entered into the device, and the outputs of the first and second ones are connected respectively to the outputs of the installation in 1 and in O of the first trigger the forward and inverse outputs of which are connected respectively to the start inputs of the first and second one-shot, direct output first, trigger

.45 is connected to the first input of the element OR NOT and p. clock input of the second trigger, the inverse output of which is connected to the first input of the NAND element, the second input of which is connected

50 with the input, reading the device code, and the output is connected to the device ready output and to the second input of the OR-NOT element, the third input of which is connected to the clock input of the device,

55 and the output is connected to the counting input of the counter.

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Claims (1)

A device for inputting information into a computer containing a keyboard, a decoder, a multiplexer, a counter, two 15 triggers, a first one-shot and an NAND element, the decoder outputs being connected to the keyboard inputs, the outputs of which are connected to the information inputs of the multiplexer, the address inputs of which are connected to the outputs of the lower bits of the counter, the outputs of the highest bits of which are connected to the inputs of the decoder, the output of the multiplexer is connected to the D-input 25 _ 'of the first trigger, the clock input of which is connected to the clock input of the device, The setting 0 at the second trigger is connected to the device code reading input, the second trigger D-input is connected to the unit potential bus, the outputs of the counter bits are connected to the information output of the device, which, in order to increase reliability, is introduced into the device the second one-shot and the OR-NOT element, and the outputs of the first and second one-shots are connected respectively to the outputs of the installation in 1 and 0 of the first trigger, the direct and inverse outputs of which are connected respectively to the trigger inputs of the of the second and one single vibrators, the direct output of the first, trigger .45 is connected to the first input of the OR-NOT element and with. the clock input of the second trigger, the inverse output of which is connected to the first input of the AND-NOT element, the second input of which is connected 50 to the input ^ of reading the device code, and the output is connected to the readiness output of the device and to the second input of the OR-NOT element, the third input of which is connected to clock input of the device, 55 and the output is connected to the counting input of the counter.