My friend Runik is currently in the process of creating decrypted ROMs for SEGA games that use the FD1094 custom CPU.
If you are able to test them on real hardware then please give feedback.
To use simply (re)program the relevant eproms with the ones downloaded and replace the custom CPU block with a normal 68000 CPU.
There is a PAL located at U9 and marked as DEC402 (on my board) inside the BM4000 unit.
I have dumped and tested this PAL.
Without the PAL fitted I got no boot up and an almost yellow looking screen with some lines through it
There has been a bit of work done recently with the bootleg version(s) of Bubble Bobble (Bobble Bobble).
The story can be found over on the Arcade Otaku forums, https://forum.arcadeotaku.com/viewtopic.php?f=26&t=5154
Basically the joaoljr has added the code found in the MCU of the original pcb into the ROMs of the bootleg and it has resulted in what is almost, if not completely perfect Bubble Bobble. Title screen and all is restored.
I did take a picture but it can out horrible so I wont add it but it does work.
Thanks to joaoljr for doing this patch.
I’ve been chatting with Charles MacDonald recently about all things PAL related and have been experimenting with using the ABI to dump combinational PAL’s with 24 pins.
After a fair amount of learning and a lot of trial and error I now have a semi decent way of recreating 24 pin PAL chips.
So, here is my first offering. The last undumped PAL chip from Rainbow Islands.
It is used for some address decoding and lives in a PAL20L8 chip. Its ID is B22-07.
That now makes a full set of PAL’s for Rainbow Islands.
I’ve created this to be programmed to a GAL22V10 device but I can recompile it for a GAL20V8 device if required.
If you try this out please give any feedback you may have.
Thanks to Charles MacDonald for all the help and inspiration you have given me over the last couple of weeks. You have the patience of a saint!
Got a Tetris that was sold as faulty.
As with pretty much any PCB I buy, a visual check was carried out and straight away I found this capacitor.
The board came with an adapter but looked a mess and the wire was far too thin on the power lines so I swapped it out.
I also found a couple of pins touching in one of the unused connectors
And finally I found the sound pot was no soldered in at all and was missing its ground pin.
I took a pot from an old scrap board and fitted it.
Now it was boot up time.
All looks ok so far, but…..
I initially thought it was a dodgy EPROM but they checked out fine. Then I realised that the EPROM at location B1 on the ROM board was missing.
I burned a new one from the Jap set and now we have this.
Everything seems to be working fine.
This board still has its battery installed in the FD1094 and surely will be coming to the end of its life by now. I don’t trust myself with a battery change but I think I have desuicided ROM’s so will just wait until it dies completely or I will sell it on as I cant imagine wanting to play this in my cab.