定时器查询法和定时器中断法实现LED闪烁

1、定时器查询法实现LED闪烁

;2013/4/23;延时1s闪烁     org   0000h                     ajmp  start     org   30hstart:mov   r0,#20      mov   p0,#0ffh;关灯      mov   TMOD,#00000001B      mov   TH0,#3CH        ;50ms定时      mov   TL0,#0B0H      setb  TR0loop: jbc   TF0,next         ;TF1为1时转移      ljmp  loopnext: mov   TH0,#3CH      mov   TL0,#0B0H      djnz  r0,loop         ;r0减1不为0跳转      cpl   p0.0      mov   r0,#20      ljmp  loop      end

2、定时器中断实现LED闪烁

;2013/4/24      org 0000h      ajmp start      org 000bh          ;定时器0的中断向量地址      ajmp time0      org 30hstart:mov  p0,#0ffh      mov  TMOD,#00000001B      mov  TH0,#3Ch      mov  TL0,#0b0h      setb EA      setb ET0      setb TR0loop: ajmp looptime0:cpl  p0.0      mov  TH0,#3Ch      mov  TL0,#0b0h      reti               ;中断返回      end