;APS00000000000000000000000000000000000000000000000000000000000000000000000000000000
***************************************
*
*	har lige lant fra system takeover code`en
*
*
*
***************************************


init:
	MOVEM.L	D0-D7/A0-A6,-(SP)

	BSR	HLA_MultiTaskingOFF
	BSR	HLA_TakeCiaaResource
	BSR	HLA_TakeCiabResource

	bsr	getvbr		; far fat i VBR`eren

	move.l	4.w,a1
	cmp.b	#60,$213(a1)	;PowerSupplyFrequency
	beq.b	NTSC
** her bor du tag hojet for om det er pal eller ntsc, da cia timerens
** hastighed afhanger af netfrequencen men da forskelden her er langt
** mindre end som ved vblank timingen burte det ikke give nogen problemer

ForcePAL
	move.l	#1773447,d0	;PAL
	bra.b	setcia
NTSC
	move.l	#1789773,d0	;NTSC
setcia
	BSR setint

	BSR	HLA_MultiTaskingON

** venter pa at venstre muse knap bliver pandet en`	
waitrotte:
	btst	#$06,$bfe001
	bne.s	waitrotte
	


	BSR	HLA_MultiTaskingOFF

	BSR	resetint
exit:	
	BSR	HLA_ReleaseCiabResource
	BSR	HLA_ReleaseCiaaResource
	BSR	HLA_MultiTaskingON

	MOVEM.L	(sp)+,D0-D7/A0-A6

	rts

resettimer:
	and.b	#$7e,$bfdf00	;alarm mode off,stop timer

	move.b	#$00,$bfda00	;timer back on 0
	move.b	#$00,$bfd900
	move.b	#$00,$bfd800
	or.b	#$81,$bfdf00	;alarm mode cia b 1,start
	rts

setalarm:
	or.b	#$80,$bfdf00	;alarm mode stop

	move.b	#$00,$bfda00	;timer start when lsb has been writtem
	move.b	#$00,$bfd900	;
	move.b	#$0F,$bfd800	;2604.16 baud...

	move.b	#$84,$bfdd00	;alarm mask set cia b interr.
	move.b	#$81,$bfdf00	;alarmmode,start
	rts			


setint:
	move.w	$dff01c,intstat	; status save int-enable
	move.w	#$7fff,$dff09a	;interrupts off
	move.l	vectorbase,a0	; henter vbr 
	move.l	$78(a0),intvek	;sav intvek

	bsr.s	resettimer	;reset alam
	bsr.s	setalarm	;set timer

	move.l	#interrupt,$78	;new intvektor ciab int p6
	
	move.w	#$e000,$dff09a		;cia b interrupt enable
	rts


resetint:
	move.w	#$4000,$dff09a	;interrupts off
	move.l	vectorbase,a0
	move.l	intvek,$78(a0)	;old vector back

	move.w	intstat,d0	;old enable status back
	or.w	#$c000,d0
	move.w	d0,$dff09a
	rts

interrupt:
	move.l	d0,-(sp)

	move.w	#$2000,$dff09c	;clear request cia b
	move.b	$bfdd00,d0
	and.b	#$04,d0		;cia b alarm ??
	bne	.ud
	move.l	#$0f00,$dff180
	move.l	#$0fff,$dff182

	bsr.L	resettimer
.ud

	move.l	(sp)+,d0
	rte
****************************************
HLA_MultiTaskingOFF:
	MOVE.L	4.w,A6
	JSR	-132(A6)		;EXEC Forbid
	JSR	-120(A6)		;EXEC Disable
	RTS
****************************************
HLA_MultiTaskingON:
	MOVE.L	4.w,A6
	JSR	-126(A6)		;EXEC Enable
	JSR	-138(A6)		;EXEC Permit
	RTS
****************************************

****************************************
HLA_TakeCiaaResource:
	MOVEQ	#0,D0			;no version
	LEA	HLA_CiaaResName(PC),A1
	MOVE.L	4.w,A6
	JSR	-498(A6)		;EXEC OpenResource
	LEA	HLA_CiaaResBase(PC),A0
	MOVE.L	D0,(A0)
	LEA	HLA_CiaaResOpened(PC),A0
	ST.B	(A0)			;Problems opening CiaaRes ??
	BEQ.W	.exit
	MOVE.L	D0,A6
	MOVEQ	#0,D0
	JSR	-24(A6)			;CIAA SetICR
	LEA	HLA_CiaaICR_REQ(PC),A0
	MOVE.B	D0,(A0)
	MOVEQ	#0,D0
	JSR	-18(A6)			;CIAA AbleICR
	LEA	HLA_CiaaICR_ENA(PC),A0
	MOVE.B	D0,(A0)
.exit	RTS

	EVEN
****************************************
HLA_TakeCiabResource:
	MOVEQ	#0,D0			;no version
	LEA	HLA_CiabResName(PC),A1
	MOVE.L	4.w,A6
	JSR	-498(A6)		;EXEC OpenResource
	LEA	HLA_CiabResBase(PC),A0
	MOVE.L	D0,(A0)
	LEA	HLA_CiabResOpened(PC),A0
	ST.B	(A0)			;Problems opening CiabRes ??
	BEQ.W	.exit
	MOVE.L	D0,A6
	MOVEQ	#0,D0
	JSR	-24(A6)			;CIAB SetICR
	LEA	HLA_CiabICR_REQ(PC),A0
	MOVE.B	D0,(A0)
	MOVEQ	#0,D0
	JSR	-18(A6)			;CIAB AbleICR
	LEA	HLA_CiabICR_ENA(PC),A0
	MOVE.B	D0,(A0)
.exit	RTS

	EVEN
****************************************
HLA_ReleaseCiaaResource:
	MOVE.L	HLA_CiaaResBase(PC),A6
	MOVE.B	#$7F,D0
	JSR	-24(A6)
	MOVE.B	HLA_CiaaICR_REQ(PC),D0
	BSET	#7,D0
	JSR	-24(A6)			;CIAA SetICR
	MOVE.B	#$7F,D0
	JSR	-18(A6)
	MOVE.B	HLA_CiaaICR_ENA(PC),D0
	BSET	#7,D0
	JSR	-18(A6)			;CIAA AbleICR
..exit	RTS
****************************************
HLA_ReleaseCiabResource:
	MOVE.L	HLA_CiabResBase(PC),A6
	MOVE.B	#$7F,D0
	JSR	-24(A6)
	MOVE.B	HLA_CiabICR_REQ(PC),D0
	BSET	#7,D0
	JSR	-24(A6)			;CIAB SetICR
	MOVE.B	#$7F,D0
	JSR	-18(A6)
	MOVE.B	HLA_CiabICR_ENA(PC),D0
	BSET	#7,D0
	JSR	-18(A6)			;CIAB AbleICR
..exit	RTS
****************************************

***********************************************************
* inputs: none
* output: d0 contains vbr.

getvbr:
	move.l	a5,-(sp)		; save it.
	moveq	#0,d0			; clear
	movea.l	4.w,a6			; exec base
	btst.b	#0,296+1(a6)		; are we at least a 68010?
	beq.b	.1			; nope.
	lea.l	vbr_exception(pc),a5	; addr of function to get vbr
	jsr	-30(a6)
.1:	move.l	(sp)+,a5		; restore it.
	rts				; return

vbr_exception:
	dc.w	$4e7a,$0801
	rte				; back to user state code

***********************************************************
vectorbase:	ds.l	1		; pointer to the vector base



HLA_CiaaResBase		DC.L	0
HLA_CiaaResName		DC.B	"ciaa.resource",0
HLA_CiaaICR_REQ		DC.B	0
HLA_CiaaICR_ENA		DC.B	0
HLA_CiaaResOpened	DC.B	0
HLA_CiabResBase		DC.L	0
HLA_CiabResName		DC.B	"ciab.resource",0
HLA_CiabICR_REQ		DC.B	0
HLA_CiabICR_ENA		DC.B	0
HLA_CiabResOpened	DC.B	0


intflag:
	dc.b	0

intvek:
	dc.l	0

intstat:
	dc.w	0

.