.include "m8def.inc"   ; ATMega8

.equ	Fo=1000000

.equ	Td=73987	;mks OK
;.equ	Td=739873	;mks OK
;.equ	Td=7398731	;mks OK

.CSEG
RESET:
	RJMP	START
.org	3
T2_CTC:
	SBIW	XL,1
	BRCS	OUT_END
	BRNE	T2_CTC_OUT
	OUT	OCR2,R17
T2_CTC_OUT:
	RETI
OUT_END:
	SBI	PORTB,0
	SET
	RETI
;*************************************************
;*************************************************
;*************************************************
START:
	LDI	XH,HIGH($100)
	LDI	XL,LOW($100)
	OUT	SPH,XH
	OUT	SPL,XL

	LDI	XH,HIGH(Td/128-1)
	LDI	XL,LOW(Td/128-1)

	LDI	R17,128-1
	OUT	OCR2,R17

LDI	R17,Td-(Td/128-1)*128-1

	LDI	R16,1<<SE
	OUT	MCUCR,R16

	LDI	R16,1<<OCIE2
	OUT	TIMSK,R16
	OUT	TIFR,R16

	SBI	DDRB,0
	CBI	PORTB,0

	LDI	R16,1<<WGM21|1<<CS20
	OUT	TCCR2,R16			; CTC Fo/1

	CLT
	SEI
WAIT:
	SLEEP
	BRTC	WAIT

	RJMP	START
.EXIT