diff --git a/src/boards/321.c b/src/boards/321.c
new file mode 100644
index 0000000..8b5f0a0
--- /dev/null
+++ b/src/boards/321.c
@@ -0,0 +1,57 @@
+/* FCEUmm - NES/Famicom Emulator
+ *
+ * Copyright notice for this file:
+ *  Copyright (C) 2020
+ *
+ * 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_mmc3.h"
+
+static uint8 reg;
+
+static void sync () {
+	if (reg &0x08)
+		setprg32(0x8000, reg &0x04 | reg >>4 &0x03);
+	else
+		MMC3_syncPRG(0x0F, reg <<2 &~0x0F);
+	MMC3_syncCHR(0x7F, reg <<5 &~0x7F);
+	MMC3_syncMirror();
+}
+
+static DECLFW (writeReg) {
+	reg = V;
+	sync();
+}
+
+static void power () {
+	reg = 0;
+	MMC3_power();
+}
+
+static void reset () {
+	reg = 0;
+	MMC3_clear();
+}
+
+void Mapper321_Init (CartInfo *info) {
+	MMC3_init(info, sync, MMC3_TYPE_AX5202P, NULL, NULL, NULL, writeReg);
+	info->Power = power;
+	info->Reset = reset;
+	AddExState(&reg, 1, 0, "EXPR");
+}
diff --git a/src/boards/490.c b/src/boards/490.c
index 67bc48a..2403ed9 100644
--- a/src/boards/490.c
+++ b/src/boards/490.c
@@ -64,4 +64,5 @@ void Mapper490_Init(CartInfo *info) {
 	info->Power = power;
 	info->Reset = reset;
 	AddExState(&reg, 1, 0, "EXPR");
+	AddExState(&pad, 1, 0, "DIPS");
 }
diff --git a/src/ines.c b/src/ines.c
index 3acaa15..650452a 100644
--- a/src/ines.c
+++ b/src/ines.c
@@ -766,6 +766,7 @@ INES_BOARD_BEGIN()
 	INES_BOARD( "830134C",                  315, BMC830134C_Init        )
 	INES_BOARD( "HP898F",                   319, Mapper319_Init         )
 	INES_BOARD( "830425C-4391T",            320, BMC830425C4391T_Init   )
+	INES_BOARD( "820310",                   321, Mapper321_Init         )
 	INES_BOARD( "K-3033",                   322, BMCK3033_Init          )
 	INES_BOARD( "FARID_SLROM_8-IN-1",       323, FARIDSLROM8IN1_Init    )
 	INES_BOARD( "FARID_UNROM_8-IN-1",       324, FARIDUNROM_Init        )
diff --git a/src/ines.h b/src/ines.h
index 5024027..35b3670 100644
--- a/src/ines.h
+++ b/src/ines.h
@@ -276,6 +276,7 @@ void Mapper294_Init(CartInfo *);
 void Mapper297_Init(CartInfo *);
 void Mapper310_Init(CartInfo *);
 void Mapper319_Init(CartInfo *);
+void Mapper321_Init(CartInfo *);
 void Mapper326_Init(CartInfo *);
 void Mapper330_Init(CartInfo *);
 void Mapper334_Init(CartInfo *);