8255流水灯.asm

来自「自己做的单片机Proteus仿真实例」· 汇编 代码 · 共 83 行

	RESET BIT  P2.5

	PAK  EQU  3FFFH
	PBK  EQU  7FFFH
	PCK  EQU  0BFFFH
	PCONT EQU 0FFFFH

       	ORG 0000H
       	LJMP START

     	ORG  0030H
START: 
	mov   a,#80h
       	mov   dptr,  #PCONT
       	movx  @dptr,a

	

	mov   a,#0FFh
       	mov   dptr,  #PAK
       	movx  @dptr,a

	mov   a,#0FFh
       	mov   dptr,  #PBK
       	movx  @dptr,a

	mov   a,#0FFh
       	mov   dptr,  #PCK
       	movx  @dptr,a

L0:	MOV   A,#0feh	;#07FH
	MOV   R7,#8
L1:	mov   dptr,  #PAK
       	movx  @dptr,a
	Rl    A
	ACALL DELAY
	DJNZ  R7,L1
	mov   a,#0FFh
       	mov   dptr,  #PAK
       	movx  @dptr,a


	MOV   A,#0feh	;#07FH
	MOV   R7,#8
L11:	mov   dptr,  #PBK
       	movx  @dptr,a
	Rl    A
	ACALL DELAY
	DJNZ  R7,L11
	mov   a,#0FFh
       	mov   dptr,  #PBK
       	movx  @dptr,a

	MOV   A,#0feh	;#07FH
	MOV   R7,#8
L111:	mov   dptr,  #PCK
       	movx  @dptr,a
	Rl    A
	ACALL DELAY
	DJNZ  R7,L111
	mov   a,#0FFh
       	mov   dptr,  #PCK
       	movx  @dptr,a
	SJMP  L0




   
DELAY1: MOV   R4,#0
AA1:   MOV   R5,#0
AA:   
       DJNZ  R5,AA
       DJNZ  R4,AA1
       RET
DELAY: MOV   R6,#5
del:   acall delay1
       djnz  r6,del
       ret

       END