From 66890eda439398d1240d244e7c7cfc8636a3fcef Mon Sep 17 00:00:00 2001
From: alpine9000 <alex.g.brown@gmail.com>
Date: Thu, 24 Mar 2016 21:12:45 +1100
Subject: [PATCH] A4000 compatibility

---
 023.slideshow/image.s     |  4 ++--
 023.slideshow/slideshow.s | 17 +++++++++++++----
 023.slideshow/utils.s     | 13 ++++++++-----
 3 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/023.slideshow/image.s b/023.slideshow/image.s
index 51820ec..6f7f9d4 100644
--- a/023.slideshow/image.s
+++ b/023.slideshow/image.s
@@ -57,12 +57,12 @@ SetupImage:
 	if INTERLACE==1
 	;; poke the bitplane pointers for the two copper lists.
 	move.l	#SCREEN_WIDTH_BYTES*SCREEN_BIT_DEPTH,d0
-	lea 	copperListAlternate,a0
+	lea 	copperListAlternateBplPtr,a0
 	jsr	PokeBitplanePointers
 	endif
 	
 	moveq.l	#0,d0
-	lea 	copperList,a0
+	lea 	copperListBplPtr,a0
 	jsr	PokeBitplanePointers
 	movem.l (sp)+,d0-a6
 	rts
diff --git a/023.slideshow/slideshow.s b/023.slideshow/slideshow.s
index f4c603c..6e16c10 100644
--- a/023.slideshow/slideshow.s
+++ b/023.slideshow/slideshow.s
@@ -8,6 +8,8 @@
 	xdef 	bitplanes2
 	xdef 	bitplanes3
 	xdef	Module
+	xdef	copperListBplPtr
+	xdef	copperListAlternateBplPtr
 	
 byteMap:
 	dc.l	Entry
@@ -84,16 +86,17 @@ Level3InterruptHandler:
 
 .verticalBlank:
 	move.w	#INTF_VERTB,INTREQ(a6)	; clear interrupt bit	
-
 	if INTERLACE==1
 	btst	#VPOSRLOFBIT,VPOSR(a6)
 	beq.s	.lof
 	lea	copperListAlternate,a0
 	move.l	a0,COP1LC(a6)
+ 	move.w  COPJMP1(a6),d0
 	bra	.done
 .lof:
 	lea	copperList,a0
 	 move.l	a0,COP1LC(a6)
+ 	move.w  COPJMP1(a6),d0
 .done
 	endif ; INTERLACE==1
 
@@ -134,7 +137,7 @@ Playrtn:
 	
 	if INTERLACE==1
 copperListAlternate:
-	;; bitplane pointers must be first else poking addresses will be incorrect
+copperListAlternateBplPtr:
 	dc.w	BPL1PTL,0
 	dc.w	BPL1PTH,0
 	dc.w	BPL2PTL,0
@@ -147,11 +150,14 @@ copperListAlternate:
 	dc.w	BPL5PTH,0
 	dc.w	BPL6PTL,0
 	dc.w	BPL6PTH,0
+	dc.w	$106,$c00	;AGA sprites, palette and dual playfield reset
+	dc.w	$1FC,0		;AGA sprites and burst reset
+	dc.l	$fffffffe
 	dc.l	$fffffffe
 	endif; INTERLACE==1
 	
 copperList:
-	;; bitplane pointers must be first else poking addresses will be incorrect
+copperListBplPtr:
 	dc.w	BPL1PTL,0
 	dc.w	BPL1PTH,0
 	dc.w	BPL2PTL,0
@@ -164,7 +170,10 @@ copperList:
 	dc.w	BPL5PTH,0
 	dc.w	BPL6PTL,0
 	dc.w	BPL6PTH,0
-	dc.l	$fffffffe		
+	dc.w	$106,$c00	;AGA sprites, palette and dual playfield reset
+	dc.w	$1FC,0		;AGA sprites and burst reset
+	dc.l	$fffffffe
+	dc.l	$fffffffe			
 	
 	align	4
 
diff --git a/023.slideshow/utils.s b/023.slideshow/utils.s
index 54920d2..e907da9 100644
--- a/023.slideshow/utils.s
+++ b/023.slideshow/utils.s
@@ -2,14 +2,17 @@
 	xdef	WaitRaster
 	xdef	Depack
 	
-	
 WaitVerticalBlank:	
-	movem.l d0-a6,-(sp)
-.loop	move.l	$dff004,d0
+	movem.l	d0,-(sp)
+.loop:	move.l	$dff004,d0
 	and.l	#$1ff00,d0
-	cmp.l	#303<<8,d0
+	cmp.l	#303<<8,d0	; wait for the scan line
 	bne.b	.loop
-	movem.l (sp)+,d0-a6
+.loop2	move.l	$dff004,d0
+	and.l	#$1ff00,d0
+	cmp.l	#303<<8,d0	; wait for the scal line to pass (A4000 is fast!)
+	beq.b	.loop2
+	movem.l (sp)+,d0
 	rts