ch14_b11-6.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 B11-6.ASM
     MS10    	EQU  	9217    		;APPROXIMATELY 10ms INTERRUPR
     INTR_CNT   EQU  	30H     		;CNT STORIAGE
     BUFFER	EQU  	31H     		;DISPLAY BUFFER
     BINARY	EQU  	32H     		;BINARY DATA STORIAGE
     ;
     SCOPE 	REG  	P3.3 	  		;CHECK BY SCOPE
     BUZZER	REG  	P3.4
     LED   	REG  	P3.7
     KEY   	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
           	MOV  	BINARY,#00H 	        ;BINARY DATA FOR DISPLAY
     ;
     $LOOP  	SETB  	KEY       		;KEY=1
             	JB    	KEY,$S100
             	MOV   	R7,#08H
             	DJNZ  	R7,$        		;WAIT A LITTLE WHILE
             	SETB   	KEY
             	JB      KEY,$S100
     ;KEY PRESS TRUE
             	MOV     A,BINARY
             	ADD     A,#01H
             	MOV     BINARY,A
             	CJNE   	A,#100,$S100	        ;IF A>=100 THEN A=0
             	MOV     BINARY,#00H 	        ;CLEAR BINARY DATA
             	ACALL  	CONV
     $WAIT 	SETB   	KEY
             	JNB     KEY,$WAIT  		;WAIT UNTIL KEY RELEASE
     ;
     $S100  	ACALL   CONV    		;CONVERT BINARY TO BCD
     ;
             	ACALL   DELAY
             	ACALL   DELAY
             	ACALL   DELAY
             	SJMP    $LOOP
     ;
     CONV   	MOV     A,BINARY
             	MOV     B,#10
             	DIV     AB      		;A=A/10,B=A MOD 10
             	ANL     A,#0FH  		;A=A AND 0FH
             	JNZ     $1
             	MOV     A,#0FH  		;IF A=00H THEN A=0FH LEADING BLANK
     $1      	SWAP   	A
             	ORL     A,B     		;A AS BCD FORM
             	MOV     BUFFER,A		;SAVE AT BUFFER
             	RET
     ;
     DELAY  	MOV    	R7,#00H
     $1      	MOV     R6,#00H
             	DJNZ   	R6,$
             	DJNZ    R7,$1
             	RET
     ;
     T0_ISR	SETB   	SCOPE
             	MOV     TH0,#(65536-MS10)/256   ;RELOAD TH0
             	MOV     TL0,#(65536-MS10).MOD. 256
             	PUSH   	A
             	PUSH   	PSW
     ;
             	MOV    	A,BUFFER
             	ANL    	A,#0FH 		        ;GET LOW NIBBLE
                SETB   	ACC.5  		        ;BIT5=1
                MOV    	P1,A   		        ;SHOW 1 DIGIT
                MOV    	R0,#30H
                DJNZ   	R0,$   		        ;DELAY
     ;inter-blanking
                CLR    	ACC.4
                CLR    	ACC.5
                MOV     P1,A   		        ;ALL DIGIT BLANK
                MOV     R0,#04H
                DJNZ    R0,$   	                ;DELAY
     ;
                MOV     A,BUFFER
                ANL     A,#F0H 	                ;GET HIGH NIBBLE
                SWAP    A                       ;SWAP A
                SETB    ACC.4  	                ;BIT4=1
                MOV     P1,A   		        ;SHOW ANOTHER DIGIT
                MOV     R0,#30H
                DJNZ    R0,$   		        ;DELAY
     ;
                CLR     ACC.4
                CLR     ACC.5
                MOV     P1,A   		        ;ALL DIGIT BLANK
     ;
     ;INTR_CNT+1
                INC     INTR_CNT
                MOV     A,INTR_CNT
                CJNE    A,#100,$T0_END
                MOV     INTR_CNT,#00H
     $T0_END    POP    	PSW
                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
     ;