keylight.asm

用89S52进行DS1820温度读取程序

KEY  BIT   P3.3
SW1  BIT   P2.2
         ORG  000H
   START: mov  sp,#40h
          mov  p2,#0ffh
          mov  p3,#0ffh
          MOV  P1,#0ffh;
          clr  key
    WAIT: JB    KEY,$       ;等候按键!
          JB   SW1,$
          
          lcall delay
         cpl   P1.7
         
         JNB   SW1,$
         JMP   wait
  DELAY: MOV  R3,#300
  D1:    MOV  R4,#300
         DJNZ  R4,$
         DJNZ  R3,D1
         RET
    END