;-----------------------------------------------------------
; titre		: rti 500ms, buzzer, led r si alim faible
; version	: 1.1
; cible		: at90s8515-8pi
; quartz	: 8mhz
; auteur	: yann leidwanger
; email		: tech@jls-info.com
;-----------------------------------------------------------

;-----------------------------------------------------------
; equivalences
;-----------------------------------------------------------
.include "8515def.inc"

.def	temp	= r16		;mcu
.def	cpt1	= r17		;pour tempo
.def	cpt2	= r18		;pour buzzer

.equ	sa	= pc7		;surveillance d'alim
.equ	ledv	= pc6		;led verte
.equ	ledr	= pc5		;led rouge
.equ	bz	= pc4		;buzzer

;-----------------------------------------------------------
; code segment
;-----------------------------------------------------------
.cseg
.org	$0000
	rjmp	reset		;reset
	rjmp	no_isr		;ext int 0
	rjmp	no_isr		;ext int 1
	rjmp	no_isr		;timer1 capture
	rjmp	no_isr		;timer1 compare a
	rjmp	no_isr		;timer1 compare b
	rjmp	t1_isr		;timer1 ovf
	rjmp	no_isr		;timer0 overflow
	rjmp	no_isr		;spi transfert complete
	rjmp	no_isr		;rx uart
	rjmp	no_isr		;udre uart
	rjmp	no_isr		;tx uart
	rjmp	no_isr		;comparator
no_isr:
	reti

;-----------------------------------------------------------
; interrupt service routines
;-----------------------------------------------------------
t1_isr:
	ldi	temp,$f0
	out	tcnt1h,temp
	ldi	temp,$bd
	out	tcnt1l,temp	;rti_time = 500ms
test_alim:
	sbic	pinc,sa
	rjmp	defaut_alim	;saute si alim ok
	cbi	portc,ledr	;led r off
cont1:
	ldi	cpt2,$ff
sound:
	cbi	portc,bz
	rcall	tempo
	sbi	portc,bz
	rcall	tempo
	dec	cpt2
	brne	sound
	reti

tempo:
	ldi	cpt1,$ff	;init compteur tempo
tempo1:
	nop
	nop
	dec	cpt1
	brne	tempo1		;teste si fin
	ret

defaut_alim:
	sbi	portc,ledr	;led r on
	rjmp	cont1

;-----------------------------------------------------------
; routines
;-----------------------------------------------------------
init_syst:
	ldi	temp,$70
	out	ddrc,temp	;pc4, pc5 et pc6 en sortie
	ldi	temp,$10
	out	portc,temp	;buzzer, led v et led r off

	ldi	temp,$f0	;real time interrupt
	out	tcnt1h,temp	;65535 - (rti_time * ck / 1024)
	ldi	temp,$bd	;rti_time = 500ms
	out	tcnt1l,temp
	ldi	temp,$05
 	out	tccr1b,temp	;init timer1 : ck / 1024
	ldi	temp,$80
	out	timsk,temp	;enable timer1 int
	sei			;enable general int

	ret

;-----------------------------------------------------------
; programme principal
;-----------------------------------------------------------
reset:
	ldi	temp,high(ramend)
	out	sph,temp
	ldi	temp,low(ramend)
	out	spl,temp	;init sp
	rcall	init_syst

main:
	rjmp	main


;-----------------------------------------------------------
; that's all folks !!!
;-----------------------------------------------------------