BCF TRISB,RB0		
		BSF TRISD,RD7		
		BCF PORTB,RB0		
CHK
		BTFSS PORTD,RD7
		BRA	PWM_50
		BSF PORTB,RB0		
		CALL DELAY
		BCF PORTB,RB0		
		CALL DELAY
		CALL DELAY
		CALL DELAY
		BRA  CHK			
PWM_50
		BSF PORTB,RB0		
		CALL DELAY
		CALL DELAY
		BCF PORTB,RB0		
		CALL DELAY
		CALL DELAY
		BRA CHK