diff --git a/src/boards/605.c b/src/boards/605.c
new file mode 100644
index 0000000..442285b
--- /dev/null
+++ b/src/boards/605.c
@@ -0,0 +1,71 @@
+/* FCE Ultra - NES/Famicom Emulator
+ *
+ * Copyright notice for this file:
+ *  Copyright (C) 2026 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"
+
+static uint8 reg[4];
+
+static void sync () {
+	if (reg[3] &0x01) { /* UNROM mode */
+		if (reg[2] &0x20) { /* 128 KiB */
+			setprg16(0x8000, reg[2] >>3 &~0x07 | reg[1] &0x07);
+			setprg16(0xC000, reg[2] >>3 &~0x07 |         0x07);
+		} else { /* 64 KiB */
+			setprg16(0x8000, reg[2] >>3 &~0x03 | reg[1] &0x07);
+			setprg16(0xC000, reg[2] >>3 &~0x03 | reg[1] &0x04 | 0x03);
+		}
+	} else { /* NROM */
+		setprg16(0x8000, reg[2] >>3 &~0x07 | reg[1] &~1);
+		setprg16(0xC000, reg[2] >>3 &~0x07 | reg[1] | 1);
+	}
+	setchr8(0);
+	setmirror(reg[0] &0x01? MI_H: MI_V);
+}
+
+static DECLFW (writeReg) {
+	reg[A >>14 &1] = V;
+	if (A <0xC000) {
+		reg[2] = A &0xFF;
+		reg[3] = A >>8;
+	}
+	sync();
+}
+
+static void reset () {
+	reg[0] = reg[1] = reg[2] = reg[3] = 0;
+	sync();
+}
+
+static void power () {
+	SetReadHandler(0x6000, 0xFFFF, CartBR);
+	SetWriteHandler(0x8000, 0xFFFF, writeReg);
+	reset();
+}
+
+static void stateRestore (int version) {
+	sync();
+}
+
+void Mapper605_Init (CartInfo *info) {
+	info->Power = power;
+	info->Reset = reset;
+	GameStateRestore = stateRestore;
+	AddExState(reg, 4, 0, "REGS");
+}
diff --git a/src/ines.c b/src/ines.c
index c4807ab..9c9d21d 100644
--- a/src/ines.c
+++ b/src/ines.c
@@ -1022,6 +1022,7 @@ INES_BOARD_BEGIN()
 	INES_BOARD( "3936",                     598, Mapper598_Init         )
 	INES_BOARD( "ET-133A",                  599, Mapper599_Init         )
 	INES_BOARD( "J-2061",                   603, Mapper603_Init         )
+	INES_BOARD( "New Star TX5/8IN1",        605, Mapper605_Init         )
 INES_BOARD_END()
 
 static uint32 iNES_get_mapper_id(void)
diff --git a/src/ines.h b/src/ines.h
index bbd73f7..8234dc8 100644
--- a/src/ines.h
+++ b/src/ines.h
@@ -491,6 +491,7 @@ void Mapper597_Init(CartInfo *);
 void Mapper598_Init(CartInfo *);
 void Mapper599_Init(CartInfo *);
 void Mapper603_Init(CartInfo *);
+void Mapper605_Init(CartInfo *);
 void FFE_Init(CartInfo *);
 
 #endif