Saturn MiSTer Core Update Adds Save Support, Improves Audio

The developer of the MiSTer FPGA’s Saturn core has saved the day with his latest update — it adds the ability to save progress in games, a long-requested feature among those who have been trying out the pre-alpha core since it was made public last year.

And that wasn’t the only major change in today’s update. Sergiy Dvodnenko, aka SRG320, also made fixes to CD audio, which was another highly requested feature, as many games have had no sound or glitchy sound until now.

His Patreon page listed all of the latest improvements:

• SCSP:
  • -fix register reading phase
  • -fix Sound Stack write
  • -add EGHOLD mode (Casper)
  • -rework DSP inputs (Command & Conquer)
  • -fix Loop processing end (Darius Gaiden)
  • -fix DMA length (Sega Ages Out run)
• SCU:
  • -fix unaligned DMA write to BBUS (Darius Gaiden)
  • -fix DMA to/from unsupported area
• Main: fix CD audio.
• Add Save support.

The latest version of the core, which comes in two versions for one or two sticks of RAM, can be downloaded from the “unstable nightlies” channel on the MiSTer Discord server.

To save a Saturn game with the MiSTer, the memory card must be initialized. A member of the community, Vampier, detailed how to do that on his page dedicated to the Saturn core:

• On the BIOS screen select ‘Manage Memory’
• Select ‘Clear’
• On the ‘Okay to Clear’ confirmation select ‘Yes’
• Go back to the main menu and you should be good to go – don’t forget to set autosave to on on the MiSTer menu screen

The core is still plagued by a problem that cropped up in the June update in which it’s looking for “boot.bin” instead of boot.rom. MiSTer owners still need to rename their boot.rom file to boot.bin to make the core work, although that still will throw up an error screen that reads “CD Bios not found.”

There’s still work to do on the audio, too. Members of the MiSTer Discord server found a lot of games that still had glitched or no sound with new update. But some games do have sound working for the first time, and when people tried out listening to audio CDs in the Saturn BIOS, it worked well.

Many users confirmed the new save feature was working in a variety of games. Other people reported a lot of games working better or at all for the first time:

“Oh my god The Legend of Oasis is fixed! It sounds normal!”

— zebadon

“Good news everyone. Street Racer now works on the core, playable and all. It never worked before.”

— Zet-sensei

“Astal sounds so legit now!”

— AdvantureTaco

“This update feels massive. Other than a few sound clicks, Radiant Silvergun runs really well. Most of the Capcom 2D run well too (forgot how good Vampire Saviour is on the Saturn) Sega Rally and VF2 seem to have a few minor glitches but very playable.”

— AndyD92

“Magic Knight Rayearth seems all but perfect now. Audio is exellent. FMVs are excellent. No noticeable issues with the in-game visuals. Plus saving now being an option. Could possibley be completable now!”

— MARI0

At the time this story is published, a member of the MiSTer Discord named Pixel Cherry Ninja is testing a variety of games with the new core in a YouTube livestream:

The first inkling that today’s update was on its way came on July 30 when Dvodnenko updated the beta branch of the MiSTer FPGA with a note about fixing the CD audio buffer reset, as Shiro reported last week. It was then accepted into the main MiSTer build Aug. 3, but it didn’t do anything from an end-user standpoint without the core being updated.

Dvodnenko continues to live behind Russian lines in Ukraine amidst the war there, making core updates — and communication — from him fairly infrequent.

He released to the public a playable build of the Saturn core for the first time in May last year, with a flurry of updates coming between late September and mid-November. A lull in updates after that was broken in mid-April this year, followed by another at the end of June and then today’s new build.

If you’re interested in supporting Dvodnenko, check out his Patreon.

The MiSTer is a field-programmable gate array, a chip that can be changed by programming it to physically emulate retro video game consoles. It includes an SD card reader from which “cores” and games can be loaded.

The cores are the programming that tells the FPGA chip how to configure itself to reproduce the performance of a console. There are cores for a wide array of consoles, from the Atari 2600 to the PlayStation — and now, at least in an early form, the Saturn.