MiSTer and FPGA

I did some more testing and changes on the MiSTer -> Astrocade interface and have made some changes. Main PCB now includes a ‘Menu’ button to bring up the main OSD. The third speech only channel has been added for Wizard of Wor and I fixed the missing track from V2.

The RGB board has also had a change, I added some mounting holes (always useful!) and have moved the composite circuit for black and white Space Zap over to here.

I have also decided on a solution to the part that has been annoying me since the first version. The volume did not go as high as the original PCB. After trying many solutions I decided the easiest is to have an optional new amplifier PCB for your cab. (Only needed if you want it to go loud)

I still need to test the composite signal for space zap and try out the three possible power supplies. (direct 5v from loom, K7805-2000 regulator or LM2596 DC-DC converter)

Anyone near Norfolk UK have a Wizard of Wor, Robby Roto or Space Zap cab I could use to test the adapter boards ?

Whilst making recent changes to the Galaxian core on MiSTer, I looked at the newest games in the Mame core as well to see what had been added that runs on standard galaxian hardware.

One, that was flagged as ‘Not Working’ was “GuttangT”

I didn’t originally plan to look at this any further, but the protection it uses can be implemented within the multigame, and now that I have sorted the graphics out it looks like that will work also!

It still needs some work on the colour prom, since that is a bad dump.

So, maybe coming to the Galaxian Multigame and/or MiSTer soon!

I know it looks the same as the pictures from the Multigame connected to a galaxian PCB, but this time I updated the Galaxian core on the MiSTer to allow me to run the multigame on it.

It should make testing things a lot quicker since the MiSTer is always connected and ready to go.

Whilst I was changing things in the Galaxian core, I thought I’d better make some changes for all MiSTer users, rather than just me, so I added in the protection for Moon Quasar so that now runs, and also extended the ROM and RAM available so that Porter (Portman on galaxian hardware) also works. I need to finish off the dip switches and do some more testing, but hopefully available soon.

Populated the necessary locations for Gorf on the new board, did some sanity checks to make sure I wasn’t putting 5v down any lines to the DE10, discovered a missing track and some layout errors.

It all works and I even managed to get the speech working from DDRAM, so you don’t actually need to fit a ram expansion to the DE10 to use it. (helps keep the cost down a little, but if you want to multigame, then you will probably need one for the other games anyway)

I still need to sort out the composite signal for space zap, the third sound channel for Wizard of Wor and try out the three possible power supplies. (direct 5v from loom, K7805-2000 regulator or LM2596 DC-DC converter)

The MiSTer core for Cosmic Guerilla has been completed.

This core uses a TMS9900 CPU where the original uses a TMS9980 (8 bit version of same CPU, just does 2 byte reads/writes instead of 1 word read/write).

However, game speed is controlled using vertical counter, so should be the same as the original.

Sound effects are all implemented using samples. (so core needs SDRAM fitted – 32Mb minimum)

Watchdog is not implemented (since it uses a weird NE556 based watchdog setup, and all my efforts to recreate one with the same timing results in it rebooting constantly)

I thought that swopping the CPU in the cosmic core to allow me to do Cosmic Guerilla would be simple. How wrong was I … 16 bit vs 8 bit, different memory read write signals, different port handling, even the reset is different!

Anyway, for the first time it actually shows something running on screen. Needs lots more doing before it’s complete, plus it currently ceases running attract mode after a couple of runs through