led.asm

广告灯左右移

 ORG 00H
START:
      MOV A,#0FFH
      CLR C
      MOV R2,#08H
LOOP:RLC A
     MOV P2,A
     CALL DELAY
     DJNZ R2,LOOP
     MOV R2,#07H
LOOP1:RRC A
     MOV P2,A
     CALL DELAY
     DJNZ R2,LOOP1
     JMP START
DELAY:MOV R3,#40
D1:   MOV R4,#20
D2:   MOV R5,#248
      DJNZ R5,$
      DJNZ R4,D2
      DJNZ R3,D1
      RET
      END