4bit-count.asm

来自「做文字显示的」· 汇编 代码 · 共 37 行

COUNT		EQU 30H 
			ORG 00H 
START:		MOV A,P3 
	ANL A,#0FH 
			MOV COUNT,A 
			MOV P1,A 
SK2:		JB P3.6,SK1 
	LCALL DELY10MS 
			JB P3.6,SK1 
			INC COUNT 
	MOV A,COUNT 
			CJNE A,#16,NEXT 
	MOV A,P3 
			ANL A,#0FH 
			MOV COUNT,A 
NEXT:		MOV P1,A 
WAIT:		JNB P3.6,WAIT 
	LJMP SK2 
SK1:	JB P3.7,SK2 
			LCALL DELY10MS 
			JB P3.7,SK2 
	DEC COUNT 
			MOV A,COUNT 
			CJNE A,#0FH,NEX 
	MOV A,P3 
			ANL A,#0FH 
			MOV COUNT,A 
NEX:		MOV P1,A 
WAIT2:		JNB P3.7,WAIT2 
	LJMP SK2 
DELY10MS:	MOV R6,#20 
			MOV R7,#248 
D1:			DJNZ R7,$ 
			DJNZ R6,D1 
	RET 
			END