From 2fd27915f725dda9c7fd39f1ba55bd3f3aecc33d Mon Sep 17 00:00:00 2001
From: Paul Gardner-Stephen <paul@servalproject.org>
Date: Mon, 22 Apr 2019 13:51:55 +0930
Subject: [PATCH] don't print strange control characters. Part solution to
 Issue #2.

---
 c64/kernal/chrout.s | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/c64/kernal/chrout.s b/c64/kernal/chrout.s
index 5def72b0..2c4d65e5 100644
--- a/c64/kernal/chrout.s
+++ b/c64/kernal/chrout.s
@@ -247,6 +247,12 @@ not_13:
 not_clearscreen:	
 	
 	;;  Convert PETSCII to screen code
+
+	;; Don't print other control codes
+	cmp #$1f
+	bcs +
+	jmp chrout_done
+*
 	
 	;; Unshifted letters
 	cmp #$40
@@ -276,9 +282,10 @@ not_upper:
 
 not_vendor:	
 
+chrout_l1:
+	
 output_literal_char:	
 	
-chrout_l1:	
 	;; Write normal character on the screen
 
 	pha