From 6247b942e5265f38dbf2f7f6ec706fa671205bda Mon Sep 17 00:00:00 2001
From: blondie7575 <qd@quinndunki.com>
Date: Sun, 10 Mar 2024 13:36:28 -0700
Subject: [PATCH] Fixed loading screen showing garbage on real hardware

---
 loaderGraphics.s | 25 +++++++++++++++++++++++++
 titleScreen.s    |  4 ++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/loaderGraphics.s b/loaderGraphics.s
index 2789cc8..621fe40 100644
--- a/loaderGraphics.s
+++ b/loaderGraphics.s
@@ -9,12 +9,16 @@ loaderPalette:
 showLoadingScreen:
 	lda #$0000
 	jsr slowColorFill
+
 	SHRVIDEO
 	SHADOWMEMORY
+
+	jsr initSCBs
 	lda #loaderPalette
 	sta PARAML0
 	lda #0
 	jsr setPalette
+
 	BORDER_COLOR #$7
 	lda #$1111
 	jsr slowColorFill
@@ -55,3 +59,24 @@ slowColorFillLoop:
 
 slowColorFillLoopDone:
 	rts
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; initSCBs
+; Initialize all scanline control bytes
+;
+; Trashes A,X
+
+initSCBs:
+	BITS8
+	lda #0
+	ldx #200	;set all 200 scbs to A
+
+initSCBsLoop:
+	dex
+	sta $e19d00,x
+	cpx #0
+	bne initSCBsLoop
+	BITS16
+	rts
+
diff --git a/titleScreen.s b/titleScreen.s
index 8a66876..36e754d 100644
--- a/titleScreen.s
+++ b/titleScreen.s
@@ -23,8 +23,8 @@ CAT1_VRAM = $5da0
 ; Shows the title screen and main game menu
 ;
 titleScreen:
-	lda #%10000000		; Set all SCBs to 320, no interrupts, palette 0
-	jsr initSCBs
+	jsr setScanLineInterruptVector
+	;jsr setVBLInterruptVector
 	stz leftScreenEdge
 
 	; Copy title screen art from where it was loaded in bank 6