ch14_b11-2.asm

51单片机基础篇 对于有一定基础的人看看 包含书中所以的源代码

     ;PROGRAM NAME B11-2.ASM
     MS10 	EQU   	9217    		;APPROXIMATELY 10ms INTERRUPR
     INTR_CNT EQU 	30H    		        ;CNT STORIAGE
     ;
     SCOPE	REG  	P3.3   		        ;CHECK BY SCOPE
     BUZZER	REG  	P3.4
     LED   	REG  	P3.7
     ;
           	ORG  	0000H
           	JMP  	START
           	ORG  	0003H   		;[DISABLE]  EXTERNAL INT0 INTERRUPT
           	RETI
           	ORG  	000BH   		;[ENABLE]  TIMER0 OVERFLOW INTERRUPT
           	JMP  	T0_ISR
     ;
           	ORG  	0013H
           	RETI            		;[DISABLE] EXTERNAL INT1 INTERRUPT
           	ORG  	001BH
           	RETI            		;[DISABLE] TIMER1 OVERFLOW INTERRUPT
           	ORG  	0023H
           	RETI            		;[DISABLE] SERIAL INTERRUPT
     ;
           	ORG  	30H
     START	MOV  	R0,#00H
           	DJNZ 	R0,$   		        ;DELAY A WHILE
           	MOV  	SP,#60H
           	MOV  	P1,#FFH
           	MOV  	P3,#FFH
           	MOV  	INTR_CNT,#00H
           	CLR   	BUZZER 		        ;P3.4=0,BUZZER OFF
           	CLR   	LED     		;P3.7=0,LED OFF
     ;
           	CALL 	SET_TMR0
     $LOOP	SJMP 	$LOOP
     ;
     T0_ISR	SETB  	SCOPE
            	MOV   	TH0,#(65536-MS10)/256   ;RELOAD TH0
             	MOV   	TL0,#(65536-MS10).MOD. 256
             	PUSH  	A
             	MOV   	A,INTR_CNT
             	CJNE  	A,#10,$1
     $1     	JNC   	$2
            	SETB  	BUZZER
            	SJMP  	$3
     $2     	CLR   	BUZZER
     $3     	INC   	INTR_CNT
            	MOV   	A,INTR_CNT
            	CJNE 	A,#100,$T0_END
            	MOV   	INTR_CNT,#00H
     $T0_END	POP   	A
             	CLR   	SCOPE
             	RETI
     ;
     SET_TMR0
             	MOV   	A,#01H 			;TIMER MODE 1
             	MOV    	TMOD,A
             	MOV    	TH0,#(65536-MS10)/256   ;RELOAD TH0
             	MOV   	TL0,#(65536-MS10).MOD. 256
             	CLR    	TF0   			;CLEAR TIMER0 FLAG
             	SETB  	TR0   			;TIMER0 START COUNT
             	SETB  	ET0   			;ENABLE TIMER0 INTERRUPT
             	SETB  	EA    			;ENABLE SYSTEM INTERRUPT
             	RET
     ;