s8.asm

来自「本文件包包括8051彻底研究书籍各章的实例源代码」· 汇编 代码 · 共 37 行

;PROGRAM NAME S8.ASM
;TEST SERIAL PORT (MODE 3)
;
BUZZER  REG     P3.4
LED     REG     P3.7
;
        ORG     0000H
RESET   MOV     R0,#00H
        DJNZ    R0,$
        CLR     LED
        CLR     BUZZER
;
        LCALL   INIT_SIO        ;SIO,TIMER INIT
START   SETB    P1.0            ;SYNC SIGNAL FOR SCOPE
        CLR     TI              ;MONITOR TxD FROM SCOPE
        MOV     A,#30H
        MOV     C,P             ;PARITY BIT
        MOV     TB8,C           ;TB8=PARITY BIT
        MOV     SBUF,A
WAIT1   JNB     TI,WAIT1
        CLR     P1.0            ;SYNC SIGNAL FOR SCOPE
        CLR     TI
        MOV     A,#32H
        MOV     C,P             ;PARITY BIT
        MOV     TB8,C           ;TB8=PARITY BIT
        MOV     SBUF,A
WAIT2   JNB     TI,WAIT2
        SJMP    START           ;RE-START
;
INIT_SIO
        MOV     TMOD,#00100000B ;TIMER 1 MODE 2
        MOV     TH1,#FDH        ;BAUD RATE=9600 BPS
        SETB    TR1             ;START TIMER 1
        MOV     SCON,#11010000B ;T/R,1 START BIT
                                ;8 BITDATA,1 TB8,1 STOP BIT
        RET