diff --git a/BizHawk.Emulation/BizHawk.Emulation.csproj b/BizHawk.Emulation/BizHawk.Emulation.csproj
index 545dd353bf..3e8c968468 100644
--- a/BizHawk.Emulation/BizHawk.Emulation.csproj
+++ b/BizHawk.Emulation/BizHawk.Emulation.csproj
@@ -148,6 +148,7 @@
+
diff --git a/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper058.cs b/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper058.cs
new file mode 100644
index 0000000000..f9e37b1482
--- /dev/null
+++ b/BizHawk.Emulation/Consoles/Nintendo/NES/Boards/Mapper058.cs
@@ -0,0 +1,107 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace BizHawk.Emulation.Consoles.Nintendo
+{
+ class Mapper058 : NES.NESBoardBase
+ {
+ /*
+ * Here are Disch's original notes:
+ ========================
+ = Mapper 058 =
+ ========================
+
+ Example Games:
+ --------------------------
+ 68-in-1 (Game Star)
+ Study and Game 32-in-1
+
+
+ Registers:
+ ---------------------------
+
+ $8000-FFFF: A~[.... .... MOCC CPPP]
+ P = PRG page select
+ C = CHR page select (8k @ $0000)
+ O = PRG Mode
+ M = Mirroring (0=Vert, 1=Horz)
+
+
+ PRG Setup:
+ ---------------------------
+
+ $8000 $A000 $C000 $E000
+ +-------------------------------+
+ PRG Mode 0: | <$8000> |
+ +-------------------------------+
+ PRG Mode 1: | $8000 | $8000 |
+ +---------------+---------------+
+ */
+
+ bool prg_mode = false;
+ int chr_reg;
+ int prg_reg;
+
+ public override bool Configure(NES.EDetectionOrigin origin)
+ {
+ switch (Cart.board_type)
+ {
+ case "MAPPER058":
+ break;
+ default:
+ return false;
+ }
+
+ SetMirrorType(EMirrorType.Vertical);
+
+ return true;
+ }
+
+ public override void SyncState(Serializer ser)
+ {
+ ser.Sync("prg_reg", ref prg_reg);
+ ser.Sync("chr_reg", ref chr_reg);
+ ser.Sync("prg_mode", ref prg_mode);
+ base.SyncState(ser);
+ }
+
+ public override void WritePRG(int addr, byte value)
+ {
+ prg_mode = addr.Bit(6);
+ if (addr.Bit(7))
+ {
+ SetMirrorType(EMirrorType.Horizontal);
+ }
+ else
+ {
+ SetMirrorType(EMirrorType.Vertical);
+ }
+
+ prg_reg = addr & 0x07;
+ chr_reg = (addr >> 3) & 0x07;
+ }
+
+ public override byte ReadPRG(int addr)
+ {
+ if (prg_mode == false)
+ {
+ return ROM[((prg_reg >> 1) * 0x8000) + addr];
+ }
+ else
+ {
+ return ROM[(prg_reg * 0x4000) + (addr & 0x3FFF)];
+ }
+ }
+
+ public override byte ReadPPU(int addr)
+ {
+ if (addr < 0x2000)
+ {
+ return VROM[(chr_reg * 0x2000) + addr];
+ }
+ return base.ReadPPU(addr);
+ }
+ }
+}