From: Toni Wilen <twilen@winuae.net>
Date: Sun, 19 Apr 2020 14:51:51 +0000 (+0300)
Subject: Undocumented DDFSTRT side-effect.
X-Git-Tag: 4400~70
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=cd39e22275e2b78325b5942d97c5fc437c49e7cd;p=francis%2Fwinuae.git

Undocumented DDFSTRT side-effect.
---

diff --git a/custom.cpp b/custom.cpp
index fbda5e27..9906b618 100644
--- a/custom.cpp
+++ b/custom.cpp
@@ -3521,7 +3521,8 @@ static void decide_line (int hpos)
 				start_bpl_dma (hstart);
 				// if ECS: pre-set plf_end_hpos if we have already passed virtual ddfstop
 				if (ecs) {
-					if (last_decide_line_hpos < hstart && hstart >= plfstop && hstart - plfstop <= DDF_OFFSET) {
+					// DDFSTRT=$18: always skip this condition. For some unknown reason.
+					if (last_decide_line_hpos < hstart && hstart >= plfstop && hstart - plfstop <= DDF_OFFSET && hstart != HARD_DDF_START_REAL + DDF_OFFSET) {
 						plf_end_hpos = plfstop + DDF_OFFSET;
 						nextstate = plf_passed_stop;
 					}