chuankou.asm

单片机与PC机的通信,下位机用汇编写的,上位机用VB实现.

org 0000H
ljmp main

org 0023h
ljmp dori
org 0040h
main:mov tmod ,#20h ;定时器设置
     mov th1,#0f3H
     mov tl1,#0F3H
     mov pcon,#80h
     mov scon,#50H  ; 串行口设置
     mov p2,#10111111B
     jb  p2.0 ,$   ;等待开机按键
     mov p2,#0feh
     mov p0,#0c0H
     call delay1S
    ; mov p2,#0FFH
     setb tr1      ;开定时器
     setb es
     setb ea
     mov r0,#1;设置初始水位为1
     setb f0
 lp: call key
     jb f0, lp
     call send
     sjmp lp


key: clr  p2.6
     jb   p2.2, l1
     inc  r0
     clr f0
     jnb  p2.2 , $     ;按下P2.2按键，水位上升
     cjne r0,#7,outkey
     mov r0,#6
     sjmp outkey
  l1:jb   p2.1 , outkey
      dec  r0
      clr f0
      jnb   p2.1 ,$   ;按下P2.1按键，水位下降
      cjne r0,#0,outkey
      mov  r0,#1
outkey:setb p2.6
      ret
      
send:mov a, r0
      mov sbuf ,a
      clr ea
      jnb ti ,$
      clr ti
      setb ea
      setb f0
      ret

dori:push dph
     push dpl
     push acc
     mov dptr,#tab2
     mov a,sbuf
     movc a,@a+dptr
     mov p0,a
     mov p2,#0feH
     clr ri
     pop acc
     pop dpl
     pop dph
     reti

tab2: db 0c0h,0f9h,0a4h,0b0h
delay1S:mov r2,#100
    d1: mov r3,#50
    d2: mov r4,#250
        djnz r4,$
        djnz r3,d2
        djnz r2,d1
        ret