MiSTer FPGA Forum

I have this strange problem with my Mister. The Spectrum core is very unstable. After loading, the occasional game runs, but most crash. Tap files won't even start loading, the tape loader sits there producing a continuous beep. If I configure the system as a 48K spectrum, it won't even boot.

All those crashes are complete reproducible, it's not like a game that didn't load at first, suddenly starts working. I've created a new install from scratch, updated everything to the latest version, but the problems remain exactly the same. All other cores i've tried (computer, console and arcade) work just fine, only the spectrum core seems to have problems.

If it helps, I have a 128MB Mister made by Antonio Villena. Does anyone have an idea where I can start looking for a solution?

First thing to test is the 128MB memory. The Spectrum core expects it to run at a higher speed than other cores, see:
https://github.com/MiSTer-devel/Main_Mi ... -use-SDRAM
You can run the memory test core, full details here:
https://www.youtube.com/watch?v=i_598L49Qrs

adrianlongland wrote: ↑Sun Oct 25, 2020 4:52 pm First thing to test is the 128MB memory. The Spectrum core expects it to run at a higher speed than other cores...

Archie runs it at higher speed, worth trying it.

I had a trouble with ROMs, where the 48K one was missing and the 48K machine didn't boot. Maybe check if you have a correct up-to-date boot.rom file. It's spectrum.rom here: https://github.com/MiSTer-devel/ZX-Spec ... r/releases

As for testing the RAM, do you have the Utilities menu in the cores list? I have a memory tester there (memtest). The top right number is the frequency at which the current test is performed. Mine passes the tests at 140 MHz. The green number is the number of times the test has passed at the current speed. The red one is the number of test failures.

Full docs here:
https://github.com/MiSTer-devel/MemTest_MiSTer

You can also download it from there if you don't have it.