From da1de8aaf57edece4b0ebb1477b46ef78bbc17ed Mon Sep 17 00:00:00 2001
From: OBattler <oubattler@gmail.com>
Date: Sun, 20 Dec 2020 21:14:24 +0100
Subject: [PATCH] 40x25 text mode and Cardex ET4000/w32p 80x25 text mode now
 actually fixes.

---
 src/video/vid_et4000w32.c | 11 +++++++++++
 src/video/vid_svga.c      |  7 ++++---
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/src/video/vid_et4000w32.c b/src/video/vid_et4000w32.c
index b3eb235bd..e856c9675 100644
--- a/src/video/vid_et4000w32.c
+++ b/src/video/vid_et4000w32.c
@@ -355,6 +355,17 @@ void et4000w32p_recalctimings(svga_t *svga)
         
 	svga->clock = (cpuclock * (double)(1ull << 32)) / svga->getclock((svga->miscout >> 2) & 3, svga->clock_gen);
 
+	if (svga->adv_flags & FLAG_NOSKEW) {
+		/* On the Cardex ET4000/W32p, adjust text mode clocks by 1. */
+        	if (!(svga->gdcreg[6] & 1) && !(svga->attrregs[0x10] & 1)) {	/*Text mode*/
+			svga->ma_latch--;
+        	        if ((svga->seqregs[1] & 8)) /*40 column*/
+                	        svga->hdisp += (svga->seqregs[1] & 1) ? 16 : 18;
+	                else
+        	                svga->hdisp += (svga->seqregs[1] & 1) ? 8 : 9;
+        	}
+	}
+
         switch (svga->bpp)
         {
                 case 15: case 16:
diff --git a/src/video/vid_svga.c b/src/video/vid_svga.c
index 0298c3f36..61dcc6d1f 100644
--- a/src/video/vid_svga.c
+++ b/src/video/vid_svga.c
@@ -445,7 +445,7 @@ svga_recalctimings(svga_t *svga)
 
     svga->interlace = 0;
 
-    svga->ma_latch = ((svga->crtc[0xc] << 8) | svga->crtc[0xd]);
+    svga->ma_latch = ((svga->crtc[0xc] << 8) | svga->crtc[0xd]) + ((svga->crtc[8] & 0x60) >> 5);
     svga->ca_adj = 0;
     
     svga->rowcount = svga->crtc[9] & 31;    
@@ -457,10 +457,11 @@ svga_recalctimings(svga_t *svga)
 		if (svga->seqregs[1] & 8) /*40 column*/ {
 			svga->render = svga_render_text_40;
 			svga->hdisp *= (svga->seqregs[1] & 1) ? 16 : 18;
+			/* Character clock is off by 1 now in 40-line modes, on all cards. */
+                        svga->ma_latch--;
+                        svga->hdisp += (svga->seqregs[1] & 1) ? 16 : 18;
 		} else {
 			svga->render = svga_render_text_80;
-			if (!(svga->adv_flags & FLAG_NOSKEW))
-				svga->ma_latch += ((svga->crtc[8] & 0x60) >> 5);
 			svga->hdisp *= (svga->seqregs[1] & 1) ? 8 : 9;
 		}
 		svga->hdisp_old = svga->hdisp;