SU1319016A1 - Information input device - Google Patents

Abstract

The invention relates to automation and computing and can be used to enter information into electronic computing machines and measuring and computing systems. The purpose of the invention is to simplify the device for inputting information. The device comprises a keyboard 1, an encoder 3, a trigger 4, a counter 5, a multiplexer 6, three registers 7-9. The introduction of the demultiplexer 6 and the connection of its outputs with the clock inputs of registers, and the information inputs of the reg isters with the outputs of the encoder, made it possible to simplify the device for entering information while simultaneously protecting the output code from the bounce of the keyboard contacts, convert the information into a binary-decimal code and store it in the output of registers to write the next number. 1 il. i (L 00 so about o

Description

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The invention relates to automation and computing and can be used to enter information into electronic computers and measuring and computing systems.

The aim of the invention is to simplify the device.

The drawing shows the proposed device.

The information input device comprises a keyboard 1, in which there is a block of resistors 2, an encoder 3, a trigger 4, a counter 5, a demultiplexer 6 and three registers 7-9.

The device works as follows.

When you first press one of the keys, a single logic level is applied to the corresponding inputs of the encoder 3. At the outputs of the encoder 3 and the information inputs of the registers 7-9, a binary-decimal code appears, corresponding to the number of the pressed key and tracking the bounce of contacts. However, writing to registers 7-9 does not occur, since at the clock inputs of registers 7-9 there is no switching from one to zero level. At the first closing of the common contact with the normally open contact of the key on the first sbi-course of the demultiplexer 6, the transition from single to zero level seHbj arriving at the clock input of register 7 appears. Information on the information inputs of the register 7 has already been established, the bounce near the normally closed contact has already been completed. The information is recorded in the register 7. At the same time, the first closure of the common contact with a normally open state causes the flip-flop 4 to trip through the single input, since the zero input of the trigger 4 removes the zero level. A single level is set at the output of trigger 4.

When the key is depressed, a bounce arising near a normally open contact and, therefore, at the clock of register 7 does not cause a change in the information on the outputs of the register, but confirms stable information on the information inputs of the register 7. When the contact is closed, the common contact with the normally closed zero input of the trigger 4 is zero, set to 0

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The zero level at the output of trigger 4. The difference from one to zero at the clock input of counter 5 causes the content of the counter to be changed by one and a code appears at the address inputs of demultiplexer 6 allowing the information from the information input of demultiplexer 6 to pass to the second output. The device is prepared to record the second digit of the code in the second register 8.

Writing a binary-decimal code to the second register 8, corresponding to the number of the second key pressed, is similar to writing the binary-decimal code to the first register 7. When the key returns to its initial state, a difference from unit to zero again occurs at the clock input of counter 5 , which leads to a change in the contents of the counter 5 by one more. At the address inputs of the demultiplexer 6, a code is established to allow the passage of information from the information input of the Yam multiplexer 6 to the third output. The device is prepared to write the third digit of the code in the third register 9.

0 Writing a binary-decimal code in the third register 9, corresponding to the number of the third key pressed, is similar to writing the binary-decimal code in the first register 7. When the key returns to its initial state, the counter input 5 again appears from the unit to the zero level . At the outputs of the counter 5 and the address inputs of the demultiplexer 6

0 is set to zero code, allowing the transfer of information from the information input of the demultiplexer 6 to the first output. The device is prepared for the next recording cycle.

Claims (1)

5, At the same time, until the next write cycle, the outputs of the registers 7-9 are kept in a binary-decimal code corresponding to the numbers of three keystrokes. Thus, the device implements protection of the output code from contact bounce, converts the decimal code specified by the keyboard into the binary-decimal code, stores it at the output of the register before recording the next number and is also simpler. Invention Formula A device for entering information containing a keypad, an encoder. trigger, counter, three registers, keyboard output group is connected to encoder inputs, first keyboard output is connected to setup input at Trigger O, second keyboard output is connected to installation input at 1 flip-flop, register outputs are information outputs of the device, characterized in that to simplify the device entered a demultiplexer, the information input of which is connected to the second output of the keyboard, the output of the trigger is connected to the counting input of the counter, the outputs of which are connected to the address inputs of the demultiplexer, the outputs of which are connected to the clock inputs of the corresponding registers, the outputs of the encoder are connected to the information inputs inputs peristr.