main.s

基于89s51的keil跑马灯工程

	ORG       0000H;
	ljmp      MAIN;
	ORG       0100H;

delay:
	mov r7,0ffh
	mov r6,0ffh
loop1:
	djnz r7,loop2
	ret
loop2:
	djnz r6,loop2
	sjmp loop1

main:
	mov sp,#60h
	mov  r0,#0feh

while1:		
	mov  P1,r0  
	call delay
	mov a,r0
	rl a
	mov r0,a
	sjmp while1


	end