复件 text1.asm

通过RS-232实现pc机与单片机的串口通信

org 0000h
ljmp main
org 0003h
ljmp zd
org 0023h
ljmp zdx
org 0100h
main:mov tmod,#20h  
mov scon ,#72h     
mov tl1,#0feh       
mov th1,#0feh
mov pcon,#00h
setb tr1             
setb ea
setb es
setb it0            
setb ex0            
clr p2.0
mov r7,#00h
loop:mov a,r7
mov dptr,#0400h
movc a,@a+dptr
mov p0,a
ljmp loop
zd:push psw
push acc
inc r7
mov sbuf,r7
pop acc
pop psw
reti
zdx:push psw
push acc
jbc ti,m1
jbc ri,m2
m2:mov r7,sbuf
mov r6,#0ffh
k:djnz r6,k
m1:pop acc
pop psw
reti
org 0400h
DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H,7FH,6fH
end