.equ	FCLK	= 16000000		;Fclk, Hz
.equ	FOUT	= 125			;output frequency, kHz

.equ T1DIV = (((FCLK/FOUT)/200)+5)/10	;CK/1

.if T1DIV > MAXWORD
.error "out of range constant"
.endif

;Init:

iDec:	ldi	temp,(1<<COM1A1) | (1<<COM1A0) | (1<<COM1B1)
	out	TCCR1A,temp

	ldi	temp,(1<<WGM12) | (1<<CS10)	
	out	TCCR1B,temp

	ldi	temp,byte2(T1DIV-1)
	out	OCR1AH,temp	
	ldi	temp,byte1(T1DIV-1)
	out	OCR1AL,temp

	in	temp,TIMSK
	ori	temp,(1<<OCIE1A)
	out	TIFR,temp		;clear pending interrupts
	out	TIMSK,temp		;output compare interrupt enable
	ret

;Timer interrupt:

FInt:	push	temp

	Skip_if_Port_Out_P_0
	rjmp	Ph1

Ph0:	ldi	temp,(1<<COM1A1) | (1<<COM1A0) | (1<<COM1B1)
	out	TCCR1A,temp
	rjmp	PhX

Ph1:	ldi	temp,(1<<COM1A1) | (1<<COM1B0) | (1<<COM1B1)
	out	TCCR1A,temp
PhX:	pop	temp
	reti