From 2ae69646641737f974b40cebcdb59ec2823b75c2 Mon Sep 17 00:00:00 2001
From: Kelvin Sherlock <ksherlock@gmail.com>
Date: Mon, 27 Sep 2021 17:55:10 -0400
Subject: [PATCH] clobbering the screen holes is bad.  The slot 4 mouse code
 stores config data in the screen holes.  on ROM 1, ESC#8 (fill screen with
 'E') would cause the slot 4 mouse to enable ADB mouse interrupts, which
 causes ProDOS to eventually error out with 255 unclaimed interrupts.

---
 vt100.screen.S | 85 +++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 80 insertions(+), 5 deletions(-)

diff --git a/vt100.screen.S b/vt100.screen.S
index 4a3677a..7edd0ee 100644
--- a/vt100.screen.S
+++ b/vt100.screen.S
@@ -318,16 +318,91 @@ fill_screen ent
 	php
 	rep #$30
 
-	ldx #$0400
-	ldy #$0401
-	lda #40*24+64-2
-	mvn $010000,$010000
 
 	ldx #$0400
 	ldy #$0401
-	lda #40*24+64-2
+	lda #40*3-2
+	mvn $010000,$010000
+
+	ldx #$0400
+	ldy #$0480
+	lda #40*3-1
+	mvn $010000,$010000
+
+	ldx #$0400
+	ldy #$0500
+	lda #40*3-1
+	mvn $010000,$010000
+
+	ldx #$0400
+	ldy #$0580
+	lda #40*3-1
+	mvn $010000,$010000
+
+	ldx #$0400
+	ldy #$0600
+	lda #40*3-1
+	mvn $010000,$010000
+
+	ldx #$0400
+	ldy #$0680
+	lda #40*3-1
+	mvn $010000,$010000
+
+	ldx #$0400
+	ldy #$0700
+	lda #40*3-1
+	mvn $010000,$010000
+
+	ldx #$0400
+	ldy #$0780
+	lda #40*3-1
+	mvn $010000,$010000
+
+* 
+	ldx #$0400
+	ldy #$0401
+	lda #40*3-2
 	mvn $000000,$000000
 
+	ldx #$0400
+	ldy #$0480
+	lda #40*3-1
+	mvn $000000,$000000
+
+	ldx #$0400
+	ldy #$0500
+	lda #40*3-1
+	mvn $000000,$000000
+
+	ldx #$0400
+	ldy #$0580
+	lda #40*3-1
+	mvn $000000,$000000
+
+	ldx #$0400
+	ldy #$0600
+	lda #40*3-1
+	mvn $000000,$000000
+
+	ldx #$0400
+	ldy #$0680
+	lda #40*3-1
+	mvn $000000,$000000
+
+	ldx #$0400
+	ldy #$0700
+	lda #40*3-1
+	mvn $000000,$000000
+
+	ldx #$0400
+	ldy #$0780
+	lda #40*3-1
+	mvn $000000,$000000
+
+
+
+
 * not needed since $0,$0 last
 *	phk
 *	plb