From 7cde78dac76bcd3556a489dc57273fa54c1ba595 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C3=ABl=20Banaan=20Ananas?=
 <happppp@users.noreply.github.com>
Date: Sun, 7 Aug 2011 01:04:59 +0000
Subject: [PATCH] (debugmsg on port c illegal write)

---
 src/emu/sound/ymf278b.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/emu/sound/ymf278b.c b/src/emu/sound/ymf278b.c
index 92876c52105..b40c13d86f9 100644
--- a/src/emu/sound/ymf278b.c
+++ b/src/emu/sound/ymf278b.c
@@ -474,6 +474,10 @@ static TIMER_CALLBACK( ymf278b_timer_ld_clear )
 
 static void ymf278b_C_w(YMF278BChip *chip, UINT8 reg, UINT8 data)
 {
+	// officially, these registers can't be accessed if NEW2 is 0
+	if (~chip->exp & 2)
+		logerror("YMF278B:  Port C illegal write %02x, %02x\n", reg, data);
+
 	chip->stream->update();
 	chip->pcmregs[reg] = data;