如下,程序本应顺序运行到最后一句死循环的。实际运行是,运行到最后一句后,大概2秒左右,又从头开始执行。请各位高手帮帮忙看看怎么回事。<br /> ORG 0000H<br /> GOTO MAIN<br /> ORG 0004H<br /> GOTO $<br />MAIN: CLRF T1CON<br /> CLRF TMR1H<br /> CLRF TMR1L<br /> CLRF INTCON<br /> BCF ADCON0,0 ;关AD<br /><br /> BSF STATUS, RP0 ;BANK1<br /> MOVLW 00H<br /> MOVWF TRISA<br /> MOVLW 07H<br /> MOVWF ADCON1 ;PA口都为数字IO<br /> CLRF PIE1 ;禁止中断<br /> <br /> BCF STATUS, RP0 ;BANK0<br /> MOVLW 00H<br /> MOVWF PORTA<br /> CLRF PIR1 ;清标志位<br /> MOVLW 30H<br /> MOVWF T1CON ;1:8预分频<br /> BSF T1CON,TMR1ON ;开TIMER1<br />T1_WAIT: BTFSS PIR1, TMR1IF<br /> GOTO T1_WAIT<br /> BSF PORTA,0<br /> BCF PIR1, TMR1IF ;清除溢出标志<br /> GOTO $<br /> |
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