keyscan.asm

单片机键盘扫描 单片机键盘扫描 单片机键盘扫描

	SJMP 30H
	ORG 30H
START:	ACALL KEYPRG
	NOP
	SJMP START
	ORG 200H
KEYPRG:	MOV P1,#0FH		
	MOV A,P1
	ANL A,#0FH
	CJNE A,#0FH,K1
	AJMP NOKEY
K1:	ACALL DL20
	MOV P1,#0FH
	MOV A,P1
	ANL A,#0FH
	CJNE A,#0FH,K2
	AJMP NOKEY
K2:     MOV R7,#00H
	MOV P1,#0EFH		
	MOV A,P1
	ANL A,#0FH
	CJNE A,#0FH,KEYNO	
K3:	MOV R7,#04H
	MOV P1,#0CFH		
	MOV A,P1
	ANL A,#0FH
	CJNE A,#0FH,KEYNO
K4:     MOV R7,#08H
	MOV P1,#0BFH
	MOV A,P1
	ANL A,#0FH
	CJNE A,#0FH,KEYNO
K5:     MOV R7,#0CH
	MOV P1,#7FH		;坏谒男?

        MOV A,P1
	ANL A,#0FH
	CJNE A,#0FH,KEYNO
	SJMP NOKEY
KEYNO:	JB ACC.0,N1
	MOV A,#0
	ADD A,R7
	AJMP KEYAND
N1:	JB ACC.1,N2
	MOV A,#1
	ADD A,R7
	AJMP KEYAND
N2:	JB ACC.2,N3
	MOV A,#2
	ADD A,R7
	AJMP KEYAND
N3:	MOV A,#3		;坏谒牧?

	ADD A,R7
	AJMP KEYAND
NOKEY:	MOV A,#0FFH
KEYAND:	CPL A			;簧⒆