From 012fbca2d80952421b4ef683be0c453071022716 Mon Sep 17 00:00:00 2001
From: negative <negativeExponent@users.noreply.github.com>
Date: Mon, 6 Mar 2023 14:03:09 +0800
Subject: [PATCH] Move mapper 205 to mapper 361/366, add proper mapper 205

- Current mapper 205 implementation moved to describe mappers 361 and 366
instead.
- Then add mapper new mapper 205.
These mapper changes should now reflect
what is described in mapper's wiki article
---
 src/boards/mmc3.cpp | 77 +++++++++++++++++++++++++++++++++++----------
 src/ines.cpp        |  4 ++-
 src/ines.h          |  1 +
 src/unif.cpp        |  1 +
 4 files changed, 66 insertions(+), 17 deletions(-)

diff --git a/src/boards/mmc3.cpp b/src/boards/mmc3.cpp
index 17d9509b..49cc7ecb 100644
--- a/src/boards/mmc3.cpp
+++ b/src/boards/mmc3.cpp
@@ -1136,20 +1136,65 @@ void Mapper198_Init(CartInfo *info) {
 	info->Power = M195Power;
 }
 
-// ---------------------------- Mapper 205 ------------------------------
-// GN-45 BOARD
+/* ---------------------------- Mapper 205 ------------------------------ */
+/* UNIF boardname BMC-JC-016-2
+https://wiki.nesdev.com/w/index.php/INES_Mapper_205 */
+
+/* 2023-02 : Update reg write logic and add solder pad */
 
 static void M205PW(uint32 A, uint8 V) {
-// GN-30A - начальная маска должна быть 1F + аппаратный переключатель на шине адреса
-	setprg8(A, (V & 0x0f) | EXPREGS[0]);
+	uint8 bank = V & ((EXPREGS[0] & 0x02) ? 0x0F : 0x1F);
+	setprg8(A, EXPREGS[0] << 4 | bank);
 }
 
 static void M205CW(uint32 A, uint8 V) {
-// GN-30A - начальная маска должна быть FF
+	uint8 bank = V & ((EXPREGS[0] & 0x02) ? 0x7F : 0xFF);
+	setchr1(A, (EXPREGS[0] << 7) | bank);
+}
+
+static DECLFW(M205Write) {
+	EXPREGS[0] = V & 3;
+	if (V & 1) {
+		EXPREGS[0] |= EXPREGS[1];
+	}
+	CartBW(A, V);
+	FixMMC3PRG(MMC3_cmd);
+	FixMMC3CHR(MMC3_cmd);
+}
+
+static void M205Reset(void) {
+	EXPREGS[0] = 0;
+	EXPREGS[1] ^= 2; /* solder pad */
+	MMC3RegReset();
+}
+
+static void M205Power(void) {
+	EXPREGS[0] = EXPREGS[1] = 0;
+	GenMMC3Power();
+	SetWriteHandler(0x6000, 0x7FFF, M205Write);
+}
+
+void Mapper205_Init(CartInfo *info) {
+	GenMMC3_Init(info, 256, 128, 8, 0);
+	pwrap = M205PW;
+	cwrap = M205CW;
+	info->Power = M205Power;
+	info->Reset = M205Reset;
+	AddExState(EXPREGS, 2, 0, "EXPR");
+}
+
+/* --------------------------- GN-45 BOARD ------------------------------ */
+
+/* Mapper 361 and 366, previously assigned as Mapper 205 */
+static void GN45PW(uint32 A, uint8 V) {
+	setprg8(A, (V & 0x0f) | EXPREGS[0]);
+}
+
+static void GN45CW(uint32 A, uint8 V) {
 	setchr1(A, (V & 0x7F) | (EXPREGS[0] << 3));
 }
 
-static DECLFW(M205Write0) {
+static DECLFW(GN45Write0) {
 	if (EXPREGS[2] == 0) {
 		EXPREGS[0] = A & 0x30;
 		EXPREGS[2] = A & 0x80;
@@ -1159,7 +1204,7 @@ static DECLFW(M205Write0) {
 		CartBW(A, V);
 }
 
-static DECLFW(M205Write1) {
+static DECLFW(GN45Write1) {
 	if (EXPREGS[2] == 0) {
 		EXPREGS[0] = V & 0x30;
 		FixMMC3PRG(MMC3_cmd);
@@ -1168,23 +1213,23 @@ static DECLFW(M205Write1) {
 		CartBW(A, V);
 }
 
-static void M205Reset(void) {
+static void GN45Reset(void) {
 	EXPREGS[0] = EXPREGS[2] = 0;
 	MMC3RegReset();
 }
 
-static void M205Power(void) {
+static void GN45Power(void) {
 	GenMMC3Power();
-	SetWriteHandler(0x6000, 0x6fff, M205Write0);
-	SetWriteHandler(0x7000, 0x7fff, M205Write1);	// OK-411 boards, the same logic, but data latched, 2-in-1 frankenstein
+	SetWriteHandler(0x6000, 0x6fff, GN45Write0);
+	SetWriteHandler(0x7000, 0x7fff, GN45Write1); /* OK-411 boards, the same logic, but data latched, 2-in-1 frankenstein */
 }
 
-void Mapper205_Init(CartInfo *info) {
+void GN45_Init(CartInfo *info) {
 	GenMMC3_Init(info, 128, 128, 8, 0);
-	pwrap = M205PW;
-	cwrap = M205CW;
-	info->Power = M205Power;
-	info->Reset = M205Reset;
+	pwrap = GN45PW;
+	cwrap = GN45CW;
+	info->Power = GN45Power;
+	info->Reset = GN45Reset;
 	AddExState(EXPREGS, 1, 0, "EXPR");
 }
 
diff --git a/src/ines.cpp b/src/ines.cpp
index 6873bdc5..9bf183f5 100644
--- a/src/ines.cpp
+++ b/src/ines.cpp
@@ -720,7 +720,7 @@ BMAPPINGLocal bmap[] = {
 	{"",					202, Mapper202_Init},
 	{"",					203, Mapper203_Init},
 	{"",					204, Mapper204_Init},
-	{"",					205, Mapper205_Init},
+	{"JC-016-2",			205, Mapper205_Init},
 	{"NAMCOT 108 Rev. C",	206, Mapper206_Init},	// Deprecated, Used to be "DEIROM" whatever it means, but actually simple version of MMC3
 	{"TAITO X1-005 Rev. B",	207, Mapper207_Init},
 	{"",					208, Mapper208_Init},
@@ -788,6 +788,8 @@ BMAPPINGLocal bmap[] = {
 	{"HP10xx/H20xx Boards",	260, BMCHPxx_Init},
 	{"810544-CA-1",			261, BMC810544CA1_Init},
 	{"AA6023/AA6023B",		268, AA6023_Init},
+	{"OK-411",				361, GN45_Init},
+	{"GN-45",				366, GN45_Init},
 	{"COOLGIRL",			342, COOLGIRL_Init },
 	{"FAM250/81-01-39-C/SCHI-24",			354, Mapper354_Init },
 
diff --git a/src/ines.h b/src/ines.h
index 04e723d7..6c95863a 100644
--- a/src/ines.h
+++ b/src/ines.h
@@ -280,6 +280,7 @@ void Mapper354_Init(CartInfo *);
 void Mapper406_Init(CartInfo *);
 
 void INX_007T_Init(CartInfo* info);
+void GN45_Init(CartInfo *info); /* previously mapper 205 */
 
 typedef struct {
 	const char *name;
diff --git a/src/unif.cpp b/src/unif.cpp
index 9bcc44f7..7b6c73a8 100644
--- a/src/unif.cpp
+++ b/src/unif.cpp
@@ -476,6 +476,7 @@ static BMAPPING bmap[] = {
 	{ "BS-400R", BS400R_Init, 0 },
 	{ "BS-4040R", BS4040R_Init, 0 },
 	{ "COOLGIRL", COOLGIRL_Init, 0 },
+	{ "JC-016-2", Mapper205_Init, 0 },
 
 	{ 0, 0, 0 }
 };