GALSPanic - New X68000 RAM board

Started by stas2k, September 11, 2020, 05:21:41 PM

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September 11, 2020, 05:21:41 PM Last Edit: September 11, 2020, 08:28:06 PM by stas2k
Dear forum, I am happy to announce that my static RAM expansion project is complete!

After trying to find reasonably priced and available RAM expansion, I decided to design and build my own. This board is based on fast and modern static RAM and is an open design available at github.

Feel free to build your own or order from me.

Prices without shipping are as follows:
2MB - 35EUR (Plays all games from Games3 directory)
4MB - 50EUR
6MB - 65EUR
8MB - 80EUR

PM me for shipping quotes.

PS: Don't trust the silkscreen on the boards in pictures.

Here are some pictures of the 8MB dev board. Production version will not have the debugging connector on top right.

Memtest success:


Amazing timing, I was just about to start looking into doing one myself based on some schematic I found in files.

I'll send you a PM.

Really appreciate your work here and thanks for making it an open design as well.


If I hadn't bought an xsimm, I would have definitely had one of these!

Nice work, well done!


This is my first ever electronics design from scratch. And my first programmable logic work.

Any feedback would be welcome. I know that for next iteration, I will route another address pin to support older machines having 1MB built in memory.


Wow! Nicely done! And yeah, thanks for making this open. PMing you now with interest.




Thanks for all the interest! Pitty you could not test it on a XVI. I need to look into overclocking my Expert to test 16Mhz as well :D

I have attached a pic of both of your boards:


Crossing fingers I'll get the XVI going again in the next few days - I "think" I have an idea where the issue is and will be starting to test to try to resolve from today.


And yes the XVI is going again.

Ran memtest68k at 16MHz and it passed 100%.  Took a couple hours to run but I figured it's more thorough than MTEST.


Great to hear that! I will update the github page.


Quote from: watto on September 20, 2020, 10:22:33 PMAnd yes the XVI is going again.

Ran memtest68k at 16MHz and it passed 100%.  Took a couple hours to run but I figured it's more thorough than MTEST.

Could you test with Geograph Seal? If the memory is not stable at 16mhz you will get a bus error


Yes, I played it for a while just yesterday.  No issues.



Got the board today -- will check it out this weekend. Thanks @stas2k!


You are welcome! If anyone wants more, I have a hefty stock now. ;)


Installed the 4MB version of this board from @stas2k in my ACE today and it works great. Finally played Daimakaimura on my X68k! Big thumbs up for this board.


Great! I will add the ACE system to the compatibility list on github.

Daimakaimura is hardcore difficult, it looks so cartooney, I did not expect that. We mostly play Final Fight whenever my brother visits, and still are not able to complete the game with 2 players.


Amazing work. I'll send you a PM once I get my Compact and my 68030 up to snuff to check for compatibility.


sent you a pm for a 6mb board. -Matthew


I've sent to you a PM for a 8MB board. Thanks!