MiSTer FPGA Forum

Clutters the code? The Recreated code is clearly delimited, it doesn't cause any confusion with non-Recreated code. Part of what was done is a cleanup of the somewhat fishy pre-existing keyboard code. It actually reduces clutter. The ghosting commit was not kept separate in the PR from the Recreated support commit. That may have caused some confusi...

Here it is (the regular core, not the composite one) with the latest framework changes and the rebased patch. Not sure what's new, but apparently the VGA_DISABLE thing was part of that update.

AmintaMister wrote: ↑Tue Nov 01, 2022 12:27 pm If you want, I can propose the patch via GitHub pull request with my Gituhb account, let me know!

If you have git skills, sure. I've uploaded the patch to https://codeberg.org/pgimeno/ZX-Spectru ... created-zx to make it simpler.

It seems I missed another sys update. I'll recompile with it ASAP.

Same thing but with the VGA_DISABLE line set to 0. Please give it a try as well. If this doesn't work then I'll give up for now because I have no idea how to compile the files. You may be luckier by submitting my patch to that repo and asking the author if it can be included as part of the Spectrum build.

- The per-frame cycle count is 71136 instead of the expected 71364 in most PAL machines. That corresponds to 312x228 (lines x cycles per line) instead of the 313x228 it should be. Hopefully this will be an easy fix. I looked at VDP interupt. The number of cycles can probably be adjusted relatively well. Looks like there's a missing one line in the...

Hi @pgimeno, I've found a ZX Spectrum Recreated Keyboard at last and it work beautifully with your patch. One question: can you also update the latest versione of the MikeS1 core (https://github.com/MikeS11/MiSTerFPGA_YC_Encoder)? Because to use the Zx Spectrum both in composite and with the rubber keyboard would be a dream! Glad you're enjoying i...

Given that Minimig comes from a different FPGA, I'd say that studying that implementation is a better idea than focusing on ao486's. My understanding is that in MiSTer, you have to communicate with the Linux side via the HPS_IO to read or write data from VHD image files. I still don't know how that works, but there are plenty of cores that do this ...

Since the .vhd cannot be written, does that mean there is no way to, for instance, save BASIC programs, or save games that have save game features, unless I use a secondary SD? As for saving BASIC programs, check this thread: https://misterfpga.org/viewtopic.php?t=2645 I think the issue reported there persists. There's a fixed core for download in...

I suspect that the reason why the 601 error occurs at 14mhz is the timeout (CX=0) caused by the Loop instruction. That makes full sense. I expected issues of that kind with the frequency switch. It's the same reason some Turbo Pascal programs stopped working on faster machines: they had a loop that they didn't expect to ever finish but it overflow...

Comparing two compilations will give different results for sure; the compilation involves random numbers for some tasks. Only if the random seed is the same, can you obtain two identical compilations. I don't even know how to get or set the seed, though. Spanish company Dinamic made a clone of this arcade for the ZX Spectrum (edit: and also for Com...

Update: I misremembered, it wasn't the dummy ROM, it was the Dr. Mario + Puzzle League ROM the one I had as boot1.rom.

Also, in the GBA core boot1.rom is no longer loading at start for some reason. Was support dropped?

drpaneas wrote: ↑Sun Oct 02, 2022 7:12 am 2. Why the directory name starts with an underscore (e.g. why `_Arcade` instead of just `Arcade`?)

Directory names starting with an underscore are visible in the menu; the rest don't show up. For example, _Arcade/cores and _Arcade/mame are not visible in the menu, but _Arcade/_alternatives is.

What Bad Toro said will work, with some changes. First, forget about how to create the image, that's not important here. The mount command is what is important. The problem is that the offset for the mount command can be different depending on how the VHD file was partitioned to start with. To find out which offset, first run: fdisk -l /media/fat/g...

I have a boot0.rom and a boot1.rom in my games/GBA folder; boot1.rom is just an empty ROM intended for displaying the full logo including the word "Nintendo" under the main GAME BOY sign the Dr. Mario + Puzzle League game. I also have games/GBA2P as a symlink to games/GBA. With that setup, trying to boot the GBA2P core results in the MiST...

I seem to remember that the Commodore datasette has an internal ADC and outputs (or receives) a digital signal from the user port. It is possible to connect it to the MiSTer user port (obviously an adapter would be needed) to read the digital signals and also control the motor? I think the appropriate thread is this one: https://misterfpga.org/vie...

There's a TOSEC collection in archive.org; does it contain the same software as in MAME?

My question is whether the setting changes either. I would guess that there's an "emulated display" and a "real display" that are separate, and that the real display's vsync is not the one that generates the interrupt, but the emulated display's, which would run at the frequency of the emulated core regardless of the refresh fre...

That's one possibility. The other is that display lag is causing muscle memory to work differently to the case with no display lag. I was fascinated by this video that tests Battletoads in an emulator vs. a NES and a MiSTer:

https://www.youtube.com/watch?v=5ZTS04rVOn0

The chip has been decapped and analysed. https://forum.vcfed.org/index.php?threads/8088-8086-microcode-disassembly.77933/ The exact breakout of cycles used by the instruction is documented in the code and in the thread I posted: https://www.vogons.org/viewtopic.php?p=703589#p703589 - Non-AAD byte takes 8 cycles. - Negating takes 1 cycle(IMUL). - So...

MicroCoreLabs wrote: ↑Sat Sep 24, 2022 6:20 pmIt would be very hard to emulate this behavior exactly

The software emulators I linked above do exactly that, and fine details on the exact algorithm and the cycles taken by each step are provided.

Does MCL86 have cycle-accurate MUL/DIV emulation? ISTR that MicroCoreLabs said it doesn't. I've found this thread discussing cycle-accurate versions of these instructions: https://www.vogons.org/viewtopic.php?t=62817 In particular this post: https://www.vogons.org/viewtopic.php?p=703576#p703576 The link in the post is obsolete, though, as it's not ...

Here's a Linux script to split boot.rom into the files mentioned: dd if=boot.rom of=GLUK661.ROM bs=8192 count=2 dd if=boot.rom of=TRDOS-5.04T bs=8192 count=2 skip=2 dd if=boot.rom of=128p-0.rom bs=8192 count=2 skip=4 dd if=boot.rom of=128-1.rom bs=8192 count=2 skip=6 dd if=boot.rom of=plus3-41-0.rom bs=8192 count=2 skip=8 dd if=boot.rom of=plus3-41...

Is the segment override bug now incorporated as a regression test? It's customary practice to add a test that fails before a bugfix and passes after it, every time a bug is squashed. That's where regression tests take their name, after all: if the bug returns, that's a regression and it will be immediately caught by the test. Some bugs have the bad...

I've worked on reverse engineering the Spectrum core's boot.rom, and this is what I found. The file contains the following ROMs, concatenated: Offs. Len. File name 00000 4000 GLUK661.ROM 04000 4000 TRDOS-5.04T 08000 4000 128p-0.rom 0C000 4000 128-1.rom 10000 4000 plus3-41-0.rom 14000 4000 plus3-41-1.rom 18000 4000 plus3-41-2.rom 1C000 4000 plus3-41...

Chris23235 wrote: ↑Tue Sep 20, 2022 6:21 pm It's not MiSTer related in any way,

Well, it might become MiSTer-related in future

The MRA is rarely named like the core. Are you sure the MRA name is kchamp.mra or jtkchamp.mra?

Not sure if that would be possible with a better CPU in the SoC and hybrid emulation.

Maybe not Voodoo, but real OPL3, a 487 coprocessor and some outstanding bugfixes that are now unfixable would become possible for ao486. Perhaps some more advanced arcades would become possible too.

The DS maybe, the N64 definitely not. This has been said in other threads.

There's always the RTC addon.

Xbytez is also an admin; maybe you can PM him about a PCXT dedicated section.

Alternatively, the "ao486 (PC 486SX)" section could be renamed "PC (ao486 / PCXT)" or something so that both computers are under a common section, but I'm not sure that would work well.