s3.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 27 行

;PROGRAM NAME S3.ASM
;TEST SERIAL PORT (MODE 1)
;
BUZZER  REG     P3.4
LED     REG     P3.7
;
RESET   MOV     R0,#00H
        DJNZ    R0,$
        CLR     LED
        CLR     BUZZER
;
        MOV     TMOD,#00100000B ;TIMER 1 MODE 2
        MOV     TH1,#FDH        ;BAUD RATE=9600 BPS
        SETB    TR1             ;START TIMER 1
        MOV     SCON,#01010000B ;T/R,1 START BIT
                                ;8 BITDATA,1 STOP BIT
START   CPL     P1.0            ;SYNC SIGNAL FOR SCOPE
        CLR     TI              ;MONITOR TxD FROM SCOPE
        MOV     A,#31H
        MOV     SBUF,A
WAIT    JNB     TI,WAIT
        SJMP    START           ;IF ANY KEY HIT THEN
;
DELAY   MOV     R0,#00H
        DJNZ    R0,$
        RET