whf.asm

pic单片机 电子秒表设计源代码,想要的快来下

 PROCESSOR 	16C74
            INCLUDE 		"P16C74B.INC "
			SEC				EQU	  0X23    	;  
	        MSEC          	EQU   0x24
	        TEMP1           EQU 0X22
            FLAG2           EQU 0X28
           

     ORG   0x00
     GOTO  START
     ORG 0x04                ; 设定中断向量
     BCF   STATUS,RP0          	 
 	   BTFSC  INTCON,T0IF       ; 判断TIER0中断标志位是否被设置
     GOTO  TMR0_ISR          	; 若是，则去执行TIMER0中断子程序
     RETFIE

START:
  	 CALL PIC_INIT					;去设置端口、TIMER0工作模式						
     BSF INTCON,GIE
     BSF INTCON,T0IE
MAIN_LOOP:
 											;程序的主体是个无限循环

     BTFSC FLAG2,7
     CALL DISPLAY
     
     GOTO MAIN_LOOP 
     

PIC_INIT:
        CLRF  INTCON           		
        BCF   INTCON,T0IE  
            		  
        BSF   STATUS,RP0         	 
        MOVLW B'00000000'      		;B’XXXXXXXX’表示单引号中的数是二
        MOVWF TRISB
        MOVLW B'00000000'
        MOVWF TRISC
      

        BCF STATUS,RP0
        MOVLW B'11000000'      		;B’XXXXXXXX’表示单引号中的数是二
        MOVWF PORTB
        MOVLW B'11000000'
        MOVWF PORTC

        BSF   STATUS,RP0        	 
        MOVLW B'11000100'       		 
        MOVWF OPTION_REG            	; 对TIMER0工作模式进行设置，32分频
        BCF  STATUS,RP0 
        MOVLW 0X06
        MOVWF TMR0        	 
                     
        CLRF SEC
        CLRF MSEC
        CLRF TEMP1
        CLRF FLAG2
        RETURN

                   

 
TMR0_ISR:
          CLRWDT
          BSF FLAG2,7
          BCF INTCON,T0IF
          MOVLW 0X06
          MOVWF TMR0
          CLRWDT
          INCF TEMP1,1
          MOVF TEMP1,0
          SUBLW .125  ;125-TEMP
          BTFSS STATUS,2
          RETFIE
          
          CLRWDT
          CLRF TEMP1
          INCF MSEC,1
          
         RETFIE
     
DISPLAY:
          MOVF MSEC,0
          SUBLW .10
          BTFSS STATUS,2
          GOTO NEXT_1
          
          CLRWDT
          CLRF MSEC
          INCF SEC,1
          MOVF SEC,0
          SUBLW .6
          BTFSS STATUS,2
          GOTO NEXT_1		  
          CLRF SEC 

NEXT_1:
        CLRWDT
	  		MOVF		MSEC,W
	  		CALL		CHAR_CODE
	  		MOVWF		PORTC
            
	  		MOVF		SEC,W
	  		CALL		CHAR_CODE
	  		MOVWF		PORTB                         
        
        BCF FLAG2,7
	  		RETURN
 
CHAR_CODE:
    ADDWF   PCL,1            ;PCL+=W
    RETLW   B'11000000'      ; Code for 0
    RETLW   B'11111001'      ; Code for 1
    RETLW   B'10100100'      ; Code for 2
    RETLW   B'10110000'      ; Code for 3
    RETLW   B'10011001'      ; Code for 4
    RETLW   B'10010010'      ; Code for 5
    RETLW   B'10000010'      ; Code for 6
    RETLW   B'11111000'      ; Code for 7
    RETLW   B'10000000'      ; Code for 8
    RETLW   B'10010000'      ; Code for 9
END