diff --git a/src/boards/301.c b/src/boards/301.c
new file mode 100644
index 0000000..4e73d23
--- /dev/null
+++ b/src/boards/301.c
@@ -0,0 +1,59 @@
+/* FCE Ultra - NES/Famicom Emulator
+ *
+ * Copyright notice for this file:
+ *  Copyright (C) 2025 NewRisingSun
+ *
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "mapinc.h"
+#include "asic_latch.h"
+
+static uint8 half;
+static uint8 reg;
+
+static void sync () {
+	setprg16(0x8000, half <<5 &0x20 | reg <<3 &0x18 | Latch_data &0x07);
+	setprg16(0xC000, half <<5 &0x20 | reg <<3 &0x18 |             0x07);
+	setchr8(0);
+	setmirror(reg &0x04? MI_H: MI_V);
+}
+
+static DECLFW (writeReg) {
+	reg = V;
+	sync();
+}
+
+static void power () {
+	half = 0;
+	reg = 0;
+	Latch_power();
+	SetWriteHandler(0x5000, 0x5FFF, writeReg);
+}
+
+static void reset () {
+	half ^= 1;
+	reg = 0;
+	RAM[0x100] =0;
+	Latch_clear();
+}
+
+void Mapper301_Init (CartInfo *info) {
+	Latch_init(info, sync, 0x8000, 0xFFFF, NULL);
+	info->Power = power;
+	info->Reset = reset;
+	AddExState(&half, 1, 0, "HALF");
+	AddExState(&reg, 1, 0, "EXPR");
+}
diff --git a/src/boards/8157.c b/src/boards/8157.c
deleted file mode 100644
index eb9224f..0000000
--- a/src/boards/8157.c
+++ /dev/null
@@ -1,81 +0,0 @@
-/* FCE Ultra - NES/Famicom Emulator
- *
- * Copyright notice for this file:
- *  Copyright (C) 2005 CaH4e3
- *
- * 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
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * GG1 boards, similar to T-262, with no Data latch
- *
- */
-
-#include "mapinc.h"
-
-static uint16 cmdreg;
-static uint8 reset;
-static SFORMAT StateRegs[] =
-{
-	{ &reset, 1, "REST" },
-	{ &cmdreg, 2, "CREG" },
-	{ 0 }
-};
-
-static void Sync(void) {
-	uint32 base = ((cmdreg & 0x060) | ((cmdreg & 0x100) >> 1)) >> 2;
-	uint32 bank = (cmdreg & 0x01C) >> 2;
-	uint32 lbank = (cmdreg & 0x200) ? 7 : ((cmdreg & 0x80) ? bank : 0);
-
-	setprg16(0x8000, base | bank);
-	setprg16(0xC000, base | lbank);
-	setmirror(((cmdreg & 2) >> 1) ^ 1);
-}
-
-static DECLFR(UNL8157Read) {
-	if ((cmdreg & 0x100) && (PRGsize[0] < (1024 * 1024))) {
-		A = (A & 0xFFF0) + reset;
-	}
-	return CartBR(A);
-}
-
-static DECLFW(UNL8157Write) {
-	cmdreg = A;
-	Sync();
-}
-
-static void UNL8157Power(void) {
-	setchr8(0);
-	SetWriteHandler(0x8000, 0xFFFF, UNL8157Write);
-	SetReadHandler(0x8000, 0xFFFF, UNL8157Read);
-	cmdreg = reset = 0;
-	Sync();
-}
-
-static void UNL8157Reset(void) {
-	cmdreg = reset = 0;
-	reset++;
-	reset &= 0x1F;
-	Sync();
-}
-
-static void UNL8157Restore(int version) {
-	Sync();
-}
-
-void UNL8157_Init(CartInfo *info) {
-	info->Power = UNL8157Power;
-	info->Reset = UNL8157Reset;
-	GameStateRestore = UNL8157Restore;
-	AddExState(&StateRegs, ~0, 0, 0);
-}
diff --git a/src/ines.c b/src/ines.c
index 2fde992..c59a7ab 100644
--- a/src/ines.c
+++ b/src/ines.c
@@ -750,7 +750,7 @@ INES_BOARD_BEGIN()
 	INES_BOARD( "TF1201",                   298, UNLTF1201_Init         )
 	INES_BOARD( "11160",                    299, BMC11160_Init          )
 	INES_BOARD( "190in1",                   300, BMC190in1_Init         )
-	INES_BOARD( "8157",                     301, UNL8157_Init           )
+	INES_BOARD( "K-3003",                   301, Mapper301_Init         )
 	INES_BOARD( "KS7057",                   302, UNLKS7057_Init         )
 	INES_BOARD( "KS7017",                   303, UNLKS7017_Init         )
 	INES_BOARD( "SMB2J",                    304, UNLSMB2J_Init          )
diff --git a/src/ines.h b/src/ines.h
index 429b8dc..b8f3d6f 100644
--- a/src/ines.h
+++ b/src/ines.h
@@ -273,6 +273,7 @@ void Mapper288_Init(CartInfo *);
 void Mapper293_Init(CartInfo *);
 void Mapper294_Init(CartInfo *);
 void Mapper297_Init(CartInfo *);
+void Mapper301_Init(CartInfo *);
 void Mapper310_Init(CartInfo *);
 void Mapper319_Init(CartInfo *);
 void Mapper321_Init(CartInfo *);
diff --git a/src/unif.c b/src/unif.c
index 9a91a53..0600839 100644
--- a/src/unif.c
+++ b/src/unif.c
@@ -430,10 +430,10 @@ static BMAPPING bmap[] = {
 	{ "43272",                      242, Mapper242_Init,        0 },
 	{ "603-5052",                   238, UNL6035052_Init,       0 },
 	{ "64in1NoRepeat",              314, BMC64in1nr_Init,       0 },
-	{ "70in1",                      236, Mapper236_Init,         0 },
+	{ "70in1",                      236, Mapper236_Init,        0 },
 	{ "70in1B",                     236, Mapper236_Init,        0 },
 	{ "810544-C-A1",                261, BMC810544CA1_Init,     0 },
-	{ "8157",                       301, UNL8157_Init,          0 },
+	{ "8157",                       242, Mapper242_Init,        0 },
 	{ "8237",                       215, UNL8237_Init,          0 },
 	{ "8237A",                      215, UNL8237A_Init,         0 },
 	{ "830118C",                    348, BMC830118C_Init,       0 },