;音頻控制
       OUTPUT BIT P1.0
       ORG   0000H
       LJMP  LOOP
       ORG   0030H
Loop:
       clr   C
       mov   OUTPUT,C
       call Delay
       setb  C
       mov    OUTPUT,C
       call Delay
       Sjmp  Loop

Delay:
       MOV   R5,#4
A1:    MOV   R6,#0FFH
A2:    MOV   R7,#0FFH
DLOOP: DJNZ  R7,DLOOP
       DJNZ  R6,A2
       DJNZ  R5,A1
       RET

       END