list	p=16f871
	include	"p16f871.inc"

__CONFIG _CP_OFF & _PWRTE_ON & _WDT_OFF & _XT_OSC & _BODEN_ON & _DEBUG_OFF & _CPD_OFF & _LVP_OFF

temp	equ	10h

	clrf	PORTB
	clrf	PORTC
	clrf	PORTD

	banksel TRISC
  	bcf 	TRISC,2
	movlw	H'FF'
	movwf	TRISB
	movlw	H'00'
	movwf	TRISD
	movlw 	H'3F'
  	movwf 	PR2
  	clrf	PIE1
	banksel TMR2
  	clrf 	TMR2
  	bsf 	T2CON,0
 	clrf	PIR1
	movlw 	H'1F'
  	movwf 	CCPR1L
	movlw 	H'0F'
	movwf 	CCP1CON
	bsf 	T2CON,2
  	
	clrf	temp

ciklus
	btfss	PIR1,1
	goto	ciklus
	btfsc	temp,0
	goto	portd_1

portd_0
	movlw	H'01'
	movwf	PORTD
	goto	vege

portd_1
	movlw	H'02'
	movwf	PORTD
	goto	vege

vege
	incf	temp
	bcf	PIR1,1
	goto	ciklus

end