LIST    P=16F84
	INCLUDE"P16F84.INC"	;file include 

 

		BSF		STATUS,RP0	;Change page1
		MOVLW	H'1F'
		MOVWF	TRISA		;PORTA ALL input
		CLRF	TRISB		;TRISB=0 PORTB all output
		BCF		STATUS,RP0	;Change page0
		CLRF	PORTB		;Clear PORTB


MAIN	BTFSC	PORTA,0	;PA0 ON?(PA0 << Low)
		GOTO	SKIP1		;PA0 OFF >> SKIP1(PA0 << High)
		MOVLW	B'00111111'	;PA0 ON >> 7segment >> 0
		MOVWF	PORTB        	; 
		GOTO	MAIN			

SKIP1	BTFSC	PORTA,1		;PA1 ON?
		GOTO	SKIP2		;PA1 OFF >> SKIP2
		MOVLW	B'00000110'	;PA1 ON >> 7segment >> 1
		MOVWF	PORTB		;
		GOTO 	MAIN

SKIP2	BTFSC	PORTA,2		;PA2 ON?
		GOTO	SKIP3		;PA2 OFF >> SKIP3
		MOVLW	B'01011011'	;PA2 ON >> 7segment >> 2
		MOVWF 	PORTB		;PORTB >> 0
		GOTO	MAIN

SKIP3	BTFSC	PORTA,3		;PA3 ON?
		GOTO	SKIP4		;PA3 OFF >> SKIP4
		MOVLW	B'01001111'	;PA3 ON >> 7segment >> 3
		MOVWF 	PORTB		;PORTB >> 0
		GOTO	MAIN

SKIP4	MOVLW	B'01110001'	;PA3 ON >> 7segment >> 3
		MOVWF 	PORTB		;PORTB >> 0
		GOTO	MAIN
 		END