请教单片机高手 我的蜂鸣器程序为什么不响

Question

START1: LCALL DISPLA1
MOV A,70H
CJNE A,#00H,SOUND
MOV A,71H
CJNE A,#00H,SOUND
MOV A,76H
CJNE A,#00H,SOUND
MOV A,77H
CJNE A,#00H,SOUND
JZ SOUND1
SOUND: MOV A,76H
CJNE A,66H,OUTSOU
MOV A,77H
CJNE A,67H,OUTSOU
MOV A,78H
CJNE A,68H,OUTSOU
MOV A,79H
CJNE A,69H,OUTSOU
DJNZ 7FH,SOUND2
DJNZ 65H,SOUND3
MOV 7FH,#08H
MOV 65H,#0CH
OUTSOU: JNB P3.4,SETMM1
AJMP START1
SETMM1: LJMP SETMM

SOUND1: CLR BUZ
AJMP OUTSOU
SOUND2: CPL BUZ
AJMP OUTSOU
SOUND3: SETB BUZ
AJMP OUTSOU

蜂鸣器主要的程序集中在这里,我先判断秒位跟分位都为零的时候整点报时 再判断时位与分位是否与闹钟设定的一致来驱动蜂鸣器嘀嘀嘀嘀的响 但为什么现实中两种情况都不响 硬件肯定没问题 蜂鸣器能响 请高手指点呀 救命!!!

Answer 1

用仿真器单步走一下，看外面引脚上的电平是否在变。

Answer 2

你检查下电路是否与蜂鸣器的电路一样