I dumped the 2 ROMs from my unit today.
These are for the A model only and need to be burned to 27c256 EPROMs.
I haven’t seen these anywhere else so hopefully someone will find them useful.
They can be found in the downloads section
More PAL dumps from Luiskiko this time from SNK’s Prisoners of War
Added more PAL dumps from Luiskiko.
These are the missing PAL’s from Rastan. Providing they work I should now have the full set.
Got a few boards today.
One of them is an original Capcom 1943 board.
Game had no sound at all.
After a quick look over the problem became apparent.
The EPROM for the sound was missing its GND leg. I replaced this with a 27c512 (data doubled up) for now as I seem to be out of 27c256 EPROM’s.
Game is fully working now.
Ive been wanting to get a RAM upgrade for my VIC20 ever since I found Robotic Liberation demo wouldn’t load from SD2IEC unless it was expanded. As eBay prices have gone stupid I opted for the homebrew piggyback method.
This method involves soldering a couple of 6264 RAM chips onto the Kernel and the BASIC ROM’s and lifting a few legs to run some wires elsewhere.
The guide I followed can be found here so I wont bother rewriting it.
Its pretty easy to follow but found it best to read through it a few times before starting.
I had already replaced the Kernel ROM in my VIC for a JiffyDOS one using one of my adapters so some of the work was already done for me regarding the pinout differences but as the guide says, best to check the operation after each RAM is fitted to confirm its working.
Anyway, here are a few pictures
You can see my custom board in the lower right hand corner of the PCB
And following the upgrade
Completed mod
And finally, Robotic Liberation
Its pretty easy to do and fairly quick once you understand the instructions.