didnt meant to commit last time, but guess I should check this in so I dont break the build

BizHawk.Emulation/Consoles/Sega/Genesis/Cart/EEPROM.cs

@@ -0,0 +1,74 @@
+using System;
+using System.Globalization;
+
+namespace BizHawk.Emulation.Consoles.Sega
+{
+    partial class Genesis
+    {
+        // State
+        bool EepromEnabled;
+
+        int EepromSize;
+        int EepromAddrMask;
+        int SdaInAddr, SdaInBit;
+        int SdaOutAddr, SdaOutBit;
+        int SclAddr, SclBit;
+
+        int SdaInCurrValue, SdaOutCurrValue, SclCurrValue;
+        int SdaInPrevValue, SdaOutPrevValue, SclPrevValue;
+
+        // Code
+
+        void InitializeEeprom(GameInfo game)
+        {
+            if (game["EEPROM"] == false) 
+                return;
+             
+            EepromEnabled = true;
+            EepromAddrMask = game.GetHexValue("EEPROM_ADDR_MASK");
+            EepromSize = EepromAddrMask + 1;
+
+            var t = game.OptionValue("SDA_IN").Split(':');
+            SdaInAddr = int.Parse(t[0], NumberStyles.HexNumber);
+            SdaInBit = int.Parse(t[1]);
+
+            t = game.OptionValue("SDA_OUT").Split(':');
+            SdaOutAddr = int.Parse(t[0], NumberStyles.HexNumber);
+            SdaOutBit = int.Parse(t[1]);
+
+            t = game.OptionValue("SCL").Split(':');
+            SclAddr = int.Parse(t[0], NumberStyles.HexNumber);
+            SclBit = int.Parse(t[1]);
+
+            SaveRAM = new byte[EepromSize];
+
+            Console.WriteLine("EEPROM enabled. Size: ${0:X} SDA_IN: ${1:X}:{2} SDA_OUT: ${3:X}:{4}, SCL: ${5:X}:{6}", 
+                EepromSize, SdaInAddr, SdaInBit, SdaOutAddr, SdaOutBit, SclAddr, SclBit);
+        }
+
+        void WriteByteEeprom(int address, byte value)
+        {
+            if (address == SdaInAddr)
+            {
+                SdaInPrevValue = SdaInCurrValue;
+                SdaInCurrValue = (value >> SdaInBit) & 1;
+                Console.WriteLine("SDA_IN: {0}", SdaInCurrValue);
+            }
+            if (address == SclAddr)
+            {
+                SclPrevValue = SclCurrValue;
+                SclCurrValue = (value >> SclBit) & 1;
+                Console.WriteLine("SCL: {0}", SclCurrValue);
+            }
+
+            // todo: logic!
+
+        }
+
+
+        byte ReadByteEeeprom()
+        {
+            return 0; // meh
+        }
+    }
+}