51 MCU matrix keyboard driver implementation-EEWORLD

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Use this matrix keyboard as microcontroller input, plug it into P1.0~P1.6 of P1 port.

I want to ask, when:

When key 1 is pressed, P0.0 of P0 port outputs high level;

Press the 2 key and P0.1 outputs high level;

…

Just go up to the 8 key.

There is also a requirement that when a key is pressed, the delay is 5 seconds and other keys are locked, and then the program returns to the starting point after 5 seconds.

;=====================================================

; As follows:

ORG 0000H

START:

MOV P0, #255

MOV P1, #255

CLR P1.0

NOP

JNB P1.4, K1

JNB P1.5, K2

JNB P1.6, K3

MOV P1, #255

CLR P1.1

NOP

JNB P1.4, K4

JNB P1.5, K5

JNB P1.6, K6

MOV P1, #255

CLR P1.2

NOP

JNB P1.4, K7

JNB P1.5, K8

; JNB P1.6, K9

SJMP START

K1: CLR P0.0

SJMP DELAY

K2: CLR P0.1

SJMP DELAY

K3: CLR P0.2

SJMP DELAY

K4: CLR P0.3

SJMP DELAY

K5: CLR P0.4

SJMP DELAY

K6: CLR P0.5

SJMP DELAY

K7: CLR P0.6

SJMP DELAY

K8: CLR P0.7

DELAY:

MOV R5, #10

DJNZ R7, $

DJNZ R6, $ - 2

DJNZ R5, $ - 4

LJMP START

END

If you need to control the output of high level by key, change all CLR in the above program to SETB.

Then: MOV P0, #255

Change to: MOV P0, #0

Reference address：51 MCU matrix keyboard driver implementation

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