From 3caa4705cae22bc9115d9649f5ddfae107a3050b Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Sat, 26 Aug 2017 12:31:19 -0400
Subject: [PATCH] Limits sync counter size.
---
Components/6845/CRTC6845.hpp | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Components/6845/CRTC6845.hpp b/Components/6845/CRTC6845.hpp
index e75a61c7f..44eee1f80 100644
--- a/Components/6845/CRTC6845.hpp
+++ b/Components/6845/CRTC6845.hpp
@@ -80,7 +80,7 @@ template <class T> class CRTC6845 {
while(cyles_remaining--) {
// check for end of horizontal sync
if(bus_state_.hsync) {
- hsync_counter_++;
+ hsync_counter_ = (hsync_counter_ + 1) & 15;
bus_state_.hsync = hsync_counter_ != (registers_[3] & 15);
}
@@ -122,7 +122,7 @@ template <class T> class CRTC6845 {
inline void do_end_of_line() {
// check for end of vertical sync
if(bus_state_.vsync) {
- vsync_counter_++;
+ vsync_counter_ = (vsync_counter_ + 1) & 15;
if(vsync_counter_ == (registers_[3] >> 4)) {
bus_state_.vsync = false;
}