请大家帮我看一下我写的有问题没,谢谢
ORG 0000H
MOV A #FEH
RET1: MOV P0,A
MOV TOMD,#01H
MOV TH1,#3CH
MOV TL1,#0B0H
SETB TR0
AGA1: JBC TF0,NEXT1
SJMP AGA1
NEXT1:
RL A
DJNZ A,RET1
BACK:
MOV P0,A
MOV TOMD,#01H
MOV TH1,#01H
MOV TL1,#0B0H
SETB TR0
AGA2:JBC TF0,NEXT2
SJMP AGA2
NEXT2:
RL A
INC A
CJNE A,#FFH, BACK
SJMP RET1
END