Sega Multi Mega bios replacement

Is the Multi Mega bios the exact same as the one used in the Mega CD 2? And while the chip in the MM is smaller, does it have the same pinout as the DIP-variants used in the regular systems?

What I want to know is, will I be able to install one of the "MCD2 JP RF" multi bios I bought from Bad_ad, or do I need a special version?

 

If the multi bios is for model 2 then you can install it. I recommend to put a socket so you can go back to the original if you want.

 

They are not the same. The CDX / Multimega bios is a different version of the MCD2 (V2.21 I believe). The chip is very, very likely a different pinout and of course it is not socketed. If you search around the interwebs I bet you can find more info on the pinout differences. There are also some sites dedicated to instructing how to do this mod. and I highly doubt a socket would fit inside there, I've only seen the DIPs soldered in.

-Segasonicfan

 

If you want to do some measurements for me, I will make you an adapter that will fit the original footprint.

I have the same thing for a few other chips there are no direct replacements for already.

 

Sorry, I've been gone the past week. There was no reply to this thread the last time I checked so I just went ahead and tried installing the MCD2 BIOS instead. I have a hot air station, so it was no problem removing the original BIOS without damaging it, should it not work.

The MCD2 BIOS I bought from you Bad_Ad84 works just fine. Checked discs of all regions and they played just fine

EDIT: I saw wolfsoft had done this already, and he used a DIP-chip as well, and I could see in his pictures that it had the exact same pinout as the original BIOS. I obviously would never try to install a new IC, just hoping that the pinout were the same. I had a pretty good feeling it would be the case this time

Also, this Multi Mega is one I had for many years, but I fucked up the VPD and broke a leg of (and ripped the trace) when I tried ENG/JAP modifying it 8 years ago when I sucked at soldering. I have fixed this by replacing the entire VPD with one from a donor MD2 instead. Really pleased that this worked out