www.pudn.com > shuangjitongxun.rar > SJTX.ASM

;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