sjtx.asm

双机串行通讯源程序(汇编),文件关联可以修改,默认为DXP2004

;甲机的通讯程序
org 0000h
p_key:   MOV P2,#0FFH
         MOV P0,#0FFH
         mov a,p0
         ;jb acc.1,p_key    ;发送键按下
main:    mov tmod,#20h
         mov th1,#0e8h
         mov tl1,#0e8h
         setb tr1
         mov scon,#50h
         mov pcon,#80h
start:   mov dph,31h
         mov dpl,30h
         mov r7,#02h
         mov r6,#00h
tx_ack:  mov a,#06h
         mov sbuf,a
wait1:   jbc ti,rx_yes
         sjmp wait1
rx_yes:  jbc ri,next1
         sjmp rx_yes
next1:   mov a,sbuf
         cjne a,#00h,tx_ack
tx_bytes:mov a,r7
         mov sbuf,a
         add a,r6
         mov r6,a
wait2:   jbc ti,tx_news
         sjmp wait2
tx_news: movx a,@dptr
         mov sbuf,a
         add a,r6
         mov r6,a
         inc dptr
wait3:   jbc ti,next2
         sjmp wait3
next2:   djnz r7,tx_news
tx_sum:  mov a,r6
         mov sbuf,a
wait4:   jbc ti,rx_0fh
         sjmp wait4
rx_0fh:  jbc ri,if_0fh
         sjmp rx_0fh
if_0fh:  mov a,sbuf
                  cjne a,#0fh,IF_0FH
         SJMP SPEAK
         sjmp $
speak:   clr p2.0
         acall dl1ms
         setb p2.0
         acall dl1ms
         sjmp speak
dl1ms:   mov r1,#32h
lp:      mov r2,#0ffh
lp1:     nop
         nop
         djnz r2,lp1
         djnz r1,lp
         ret

end