N64 - start a system bus memory domain, doesn't yet work

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.IMemoryDomains.cs

@@ -113,6 +113,28 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 				MakeMemoryDomain("Mempak 4", mupen64plusApi.N64_MEMORY.MEMPAK4, MemoryDomain.Endian.Little);
 			}
 
+
+			Func<int, byte> peekByte;
+			Action<int, byte> pokeByte;
+
+			peekByte = delegate(int addr)
+				{
+					return api.m64p_read_memory_8((uint)addr);
+				};
+				pokeByte = delegate(int addr, byte val)
+				{
+					api.m64p_write_memory_8((uint)addr, val);
+				};
+
+			_memoryDomains.Add(new MemoryDomain
+				(
+					name: "Sytem Bus",
+					size: int.MaxValue,
+					endian: MemoryDomain.Endian.Big,
+					peekByte: peekByte,
+					pokeByte: pokeByte
+				));
+
 			MemoryDomains = new MemoryDomainList(_memoryDomains);
 		}
 	}

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/NativeAPI/mupen64plusCoreApi.cs

@@ -260,6 +260,22 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64.NativeApi
 		delegate m64p_error CoreDoCommandRenderCallback(m64p_command Command, int ParamInt, RenderCallback ParamPtr);
 		CoreDoCommandRenderCallback m64pCoreDoCommandRenderCallback;
 
+		/// <summary>
+		/// Reads from the "system bus"
+		/// </summary>
+		/// <returns></returns>
+		[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+		public delegate byte biz_read_memory(uint addr);
+		public biz_read_memory m64p_read_memory_8;
+
+		/// <summary>
+		/// Writes to the "system bus"
+		/// </summary>
+		/// <returns></returns>
+		[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+		public delegate void biz_write_memory(uint addr, byte value);
+		public biz_write_memory m64p_write_memory_8;
+
 		// These are common for all four plugins
 
 		/// <summary>

libmupen64plus/mupen64plus-core/src/debugger/dbg_memory.c

@@ -428,6 +428,12 @@ void write_memory_16(uint32 addr, uint16 value)
     write_memory_8(addr + 1, value & 0xFF); //then again, it works unaligned
 }
 
+
+EXPORT uint8 CALL biz_read_memory(uint32 addr)
+{
+	return read_memory_8(addr);
+}
+
 uint8 read_memory_8(uint32 addr)
 {
     uint32 word;
@@ -436,6 +442,11 @@ uint8 read_memory_8(uint32 addr)
     return (word >> ((3 - (addr & 3)) * 8)) & 0xFF;
 }
 
+EXPORT void CALL biz_write_memory(uint32 addr, uint8 value)
+{
+	write_memory_8(addr, value);
+}
+
 void write_memory_8(uint32 addr, uint8 value)
 {
     uint32 word, mask;