From 0979e66e1ce9376d44dbf430dfed97badc50cb2f Mon Sep 17 00:00:00 2001
From: negativeExponent <negativeExponent@users.noreply.github.com>
Date: Sat, 22 Feb 2020 21:37:34 +0800
Subject: [PATCH] Mapper 235 update support for 1MB/2MB carts and cart with
 unrom block

---
 src/boards/235.c   | 83 +++++++++++++++++++++++++++++++++++++++-------
 src/ines-correct.h |  5 +++
 src/ines.c         |  2 +-
 3 files changed, 77 insertions(+), 13 deletions(-)

diff --git a/src/boards/235.c b/src/boards/235.c
index b2aca1d..f7d428a 100644
--- a/src/boards/235.c
+++ b/src/boards/235.c
@@ -2,6 +2,7 @@
  *
  * Copyright notice for this file:
  *  Copyright (C) 2005 CaH4e3
+ *  Copyright (C) 2020 negativeExponent
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -19,35 +20,76 @@
  */
 
 #include "mapinc.h"
+#include "../ines.h"
+
+static uint8 *CHRRAM;
+static uint32 CHRRAMSIZE;
 
 static uint16 cmdreg;
+static uint8 unrom, reg, type, openbus;
+
 static SFORMAT StateRegs[] =
 {
-	{ &cmdreg, 2, "CREG" },
+	{ &cmdreg,  2 | FCEUSTATE_RLSB, "CREG" },
+	{ &unrom,   1, "UNRM" },
+	{ &reg,     1, "UNRG" },
+	{ &type,    1, "TYPE" },
+	{ &openbus, 1, "OPNB" },
 	{ 0 }
 };
 
 static void Sync(void) {
-	if (cmdreg & 0x400)
-		setmirror(MI_0);
-	else
-		setmirror(((cmdreg >> 13) & 1) ^ 1);
-	if (cmdreg & 0x800) {
-		setprg16(0x8000, ((cmdreg & 0x300) >> 3) | ((cmdreg & 0x1F) << 1) | ((cmdreg >> 12) & 1));
-		setprg16(0xC000, ((cmdreg & 0x300) >> 3) | ((cmdreg & 0x1F) << 1) | ((cmdreg >> 12) & 1));
-	} else
-		setprg32(0x8000, ((cmdreg & 0x300) >> 4) | (cmdreg & 0x1F));
+	if (type && unrom) {
+		setprg16(0x8000, 0x80 | reg & 7);
+		setprg16(0xC000, 0x80 | 7);
+		setchr8(0);
+		setmirror(MI_V);
+	} else {
+		uint8 bank = ((cmdreg & 0x300) >> 3) | (cmdreg & 0x1F);
+		if (cmdreg & 0x400)
+			setmirror(MI_0);
+		else
+			setmirror(((cmdreg >> 13) & 1) ^ 1);
+		if (bank >= PRGsize[0] / 32768)
+			openbus = 1;
+		else if (cmdreg & 0x800) {
+			setprg16(0x8000, (bank << 1) | ((cmdreg >> 12) & 1));
+			setprg16(0xC000, (bank << 1) | ((cmdreg >> 12) & 1));
+		} else
+			setprg32(0x8000, bank);
+		setchr8(0);
+	}
+}
+
+static DECLFR(M235Read) {
+	if (openbus) {
+		openbus = 0;
+		return X.DB;
+	}
+	return CartBR(A);
 }
 
 static DECLFW(M235Write) {
 	cmdreg = A;
+	reg = V;
+	Sync();
+}
+
+static void M235Close(void) {
+	if (CHRRAM)
+		free(CHRRAM);
+	CHRRAM = NULL;
+}
+
+static void M235Reset(void) {
+	cmdreg = 0;
+	unrom = (unrom + type) & 1;
 	Sync();
 }
 
 static void M235Power(void) {
-	setchr8(0);
 	SetWriteHandler(0x8000, 0xFFFF, M235Write);
-	SetReadHandler(0x8000, 0xFFFF, CartBR);
+	SetReadHandler(0x8000, 0xFFFF, M235Read);
 	cmdreg = 0;
 	Sync();
 }
@@ -57,7 +99,24 @@ static void M235Restore(int version) {
 }
 
 void Mapper235_Init(CartInfo *info) {
+	info->Reset = M235Reset;
 	info->Power = M235Power;
+	info->Close = M235Close;
 	GameStateRestore = M235Restore;
 	AddExState(&StateRegs, ~0, 0, 0);
+
+	/* some nes 2.0 header do can have no chr-ram.
+	 * one such cart is 210-in-1 and Contra 4-in-1 (212-in-1,212 Hong Kong,Reset Based)(Unl).nes (0x745A6791)
+	 */
+	if (CHRsize[0] == 0) {
+		CHRRAMSIZE = 8192;
+		CHRRAM = (uint8*)FCEU_gmalloc(CHRRAMSIZE);
+		SetupCartCHRMapping(0, CHRRAM, CHRRAMSIZE, 1);
+		AddExState(CHRRAM, CHRRAMSIZE, 0, "CRAM");
+	}
+
+	type = 0;
+	/* carts with unrom game, reset-based */
+	if ((info->CRC32) == 0x745A6791) /* 210-in-1 and Contra 4-in-1 (212-in-1,212 Hong Kong,Reset Based)(Unl).nes */
+		type = 1;
 }
diff --git a/src/ines-correct.h b/src/ines-correct.h
index f2d4cb2..3fda31e 100644
--- a/src/ines-correct.h
+++ b/src/ines-correct.h
@@ -316,6 +316,11 @@
 	{0xd09f778d,	217,	   -1},	/* 9999999-in-1 (Static Splash, Alt Mapper)[p1][!] */
 	{0x62ef6c79,	232,		8},	/* Quattro Sports -Aladdin */
 	{0x2705eaeb,	234,	   -1},	/* Maxi 15 */
+	{0x80CBCACB,	235,	   -1},	/* 100-in-1 (Unl).nes */
+	{0x6175B9A0,	235,	   -1},	/* 150_in_1_199x-ASp */
+	{0x745A6791,	235,	   -1},	/* 210-in-1 and Contra 4-in-1 (212-in-1,212 Hong Kong,Reset Based)(Unl).nes */
+	{0xDF81364D,	235,	   -1},	/* 260-in-1 [p1][!].nes */
+	{0xA38F2F1D,	235,	   -1},	/* 1500-in-1.nes */
 	{0x6f12afc5,	235,	   -1},	/* Golden Game 150-in-1 */
 	{0x2537b3e6,	241,	   -1},	/* Dance Xtreme - Prima (Unl) */
 	{0x11611e89,	241,	   -1},	/* Darkseed (Unl) [p1] */
diff --git a/src/ines.c b/src/ines.c
index f4423e1..80f2b59 100644
--- a/src/ines.c
+++ b/src/ines.c
@@ -630,7 +630,7 @@ static BMAPPINGLocal bmap[] = {
 	{(uint8_t*)"BMC QUATTRO",			232, Mapper232_Init},
 	{(uint8_t*)"BMC 22+20-in-1 RST",	233, Mapper233_Init},
 	{(uint8_t*)"BMC MAXI",			234, Mapper234_Init},
-	{(uint8_t*)"",					235, Mapper235_Init},
+	{(uint8_t*)"Golden Game",	235, Mapper235_Init},
 /*	{(uint8_t*)"",					236, Mapper236_Init}, */
 	{(uint8_t*)"Teletubbies / Y2K",	237, Mapper237_Init},
 	{(uint8_t*)"UNL6035052",			238, UNL6035052_Init},