From f6b5f60399ee06e3f9ced96d2a8b3635b46ea212 Mon Sep 17 00:00:00 2001
From: NewRisingSun <8vytz1+dhp372pv94ebg@sharklasers.com>
Date: Thu, 29 Dec 2022 23:12:47 +0100
Subject: [PATCH] Add submapper 1 to mapper 452

---
 src/boards/452.c | 108 ++++++++++++++++++++++++++++++++---------------
 1 file changed, 73 insertions(+), 35 deletions(-)

diff --git a/src/boards/452.c b/src/boards/452.c
index 5b8b3c9..bd83f51 100644
--- a/src/boards/452.c
+++ b/src/boards/452.c
@@ -18,44 +18,85 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
- 
+
 /* DS-9-27. Absolutely insane PCB that overlays 8 KiB of WRAM into a selectable position between $8000 and $E000. */
- 
+
 #include "mapinc.h"
 
 static uint8 *WRAM;
 static uint32 WRAMSIZE;
 static uint16 latch[2];
+static uint8 submapper;
 
+static void SetWRAM(uint16 A) {
+	setprg8r(0x10, A, 0);
+	SetWriteHandler(A, A |0x1FFF, CartBW);
+}
+
+static DECLFW(Mapper452_WriteLatch);
 static void Mapper452_Sync(void) {
-	uint8 wramBank = latch[1] >>3 &6 |8;
-	if (latch[1] &2) {
-		setprg8(0x8000, latch[0] >>1);
-		setprg8(0xA000, latch[0] >>1);
-		setprg8(0xC000, latch[0] >>1);
-		setprg8(0xE000, latch[0] >>1);
-		setprg8r(0x10, (wramBank ^4) <<12, 0);
-	} else
-	if (latch[1] &8) {
-		setprg8(0x8000, latch[0] >>1 &~1 |0);
-		setprg8(0xA000, latch[0] >>1 &~1 |1);
-		setprg8(0xC000, latch[0] >>1 &~1 |2);
-		setprg8(0xE000, latch[0] >>1 &~1 |3 | latch[1] &4 | (latch[1] &0x04 && latch[1] &0x40? 8: 0));
+	SetWriteHandler(0x8000, 0xFFFF, Mapper452_WriteLatch);
+	if (submapper ==1) {
+		switch(latch[0] &0xF000) {
+		case 0xA000:
+			setprg16(0x8000, latch[0] >>1);
+			setprg8 (0xC000, 0);
+			SetWRAM(latch[0] <<4 &0x6000 |0x8000);
+			break;
+		case 0xC000:
+			setprg16(0x8000, latch[0] >>1 |0);
+			setprg16(0xC000, latch[0] >>1 |1);
+			SetWRAM(latch[0] <<4 &0x6000 |0x8000);
+			break;
+		case 0xD000:
+			setprg8(0x8000, latch[0]);
+			setprg8(0xA000, latch[0]);
+			setprg8(0xC000, latch[0]);
+			setprg8(0xE000, latch[0]);
+			SetWRAM(latch[0] <<4 &0x2000 |0x8000);
+			SetWRAM(latch[0] <<4 &0x2000 |0xC000);
+			break;
+		case 0xE000:
+			setprg16(0x8000, latch[0] >>1);
+			setprg16(0xC000, latch[0] &0x100? (latch[0] >>1 |7): 0);
+			SetWRAM(latch[0] <<4 &0x6000 |0x8000);
+			break;
+		default:
+			setprg16(0x8000, latch[0] >>1);
+			setprg16(0xC000, 0);
+			break;
+		}
+		setchr8(0);
+		setmirror(latch[0] &0x800? MI_H: MI_V);
 	} else {
-		setprg16(0x8000, latch[0] >>2);
-		setprg16(0xC000, 0);
+		uint8 wramBank = latch[1] >>3 &6 |8;
+		if (latch[1] &2) {
+			setprg8(0x8000, latch[0] >>1);
+			setprg8(0xA000, latch[0] >>1);
+			setprg8(0xC000, latch[0] >>1);
+			setprg8(0xE000, latch[0] >>1);
+			SetWRAM((wramBank ^4) <<12);
+		} else
+		if (latch[1] &8) {
+			setprg8(0x8000, latch[0] >>1 &~1 |0);
+			setprg8(0xA000, latch[0] >>1 &~1 |1);
+			setprg8(0xC000, latch[0] >>1 &~1 |2);
+			setprg8(0xE000, latch[0] >>1 &~1 |3 | latch[1] &4 | (latch[1] &0x04 && latch[1] &0x40? 8: 0));
+		} else {
+			setprg16(0x8000, latch[0] >>2);
+			setprg16(0xC000, 0);
+		}
+		SetWRAM(wramBank <<12);
+		setchr8(0);
+		setmirror(latch [1] &1 ^1);
 	}
-	setprg8r(0x10, wramBank <<12, 0);
-	setchr8(0);
-	setmirror(latch [1] &1 ^1);
-	
 }
 
 static DECLFW(Mapper452_WriteLatch) {
-	latch[0] =A &0xFFF;
+	CartBW(A, V);
+	latch[0] =A &0xFFFF;
 	latch[1] =V;
 	Mapper452_Sync();
-	/* Do not relay to CartBW, as RAM mapped to locations other than $8000-$DFFF are not write-enabled. */
 }
 
 static void Mapper452_Reset(void) {
@@ -64,35 +105,32 @@ static void Mapper452_Reset(void) {
 }
 
 static void Mapper452_Power(void) {
-	
 	latch[0] =latch[1] =0;
+	SetReadHandler(0x6000, 0xFFFF, CartBR);
 	Mapper452_Sync();
-	SetReadHandler(0x8000, 0xFFFF, CartBR);
-	SetWriteHandler(0x8000, 0xDFFF, Mapper452_WriteLatch);
-	SetWriteHandler(0xE000, 0xFFFF, CartBW);
-    FCEU_CheatAddRAM(WRAMSIZE >> 10, 0x6000, WRAM);
+	FCEU_CheatAddRAM(WRAMSIZE >> 10, 0x6000, WRAM);
 }
 
 static void Mapper452_Close(void) {
-   if (WRAM)
-      FCEU_gfree(WRAM);
-   WRAM = NULL;
+	if (WRAM)
+		FCEU_gfree(WRAM);
+	WRAM = NULL;
 }
 
 static void StateRestore(int version) {
-   Mapper452_Sync();
+	Mapper452_Sync();
 }
 
 void Mapper452_Init(CartInfo *info) {
+	submapper =info->submapper;
 	info->Reset = Mapper452_Reset;
 	info->Power = Mapper452_Power;
 	info->Close = Mapper452_Close;
 	GameStateRestore = StateRestore;
 
-	WRAMSIZE = 8192;
-	WRAM = (uint8*) FCEU_gmalloc(WRAMSIZE);
+	WRAMSIZE =8192;
+	WRAM =(uint8*) FCEU_gmalloc(WRAMSIZE);
 	SetupCartPRGMapping(0x10, WRAM, WRAMSIZE, 1);
 	AddExState(WRAM, WRAMSIZE, 0, "WRAM");
-
 	AddExState(&latch, 4, 0, "LATC");
 }