SD card in second SD slot on I/O for ao486?

Composite Lord
Posts: 6
Joined: Sat Oct 16, 2021 4:52 pm
Has thanked: 2 times

SD card in second SD slot on I/O for ao486?

Unread post by Composite Lord »

Can I use the second I/O SD card slot for game VHDs running the ao486 core? I plan to run the eXoFlynn pack and scripts but have nowhere near the space on my main DE10 SD card, and if it's possible how would I go about doing that exactly since it differs from what the standard ao486/eXoFlynn setup guides instructs?

Sorry for asking for a bit of hand-holding here, I've setup most other cores using guides and experimentation, it's just that I have to go a bit outside the box here due to storage limitations and want to start off right so I don't end up only banging my head against the wall for days trying out infinite setup variations and getting nowhere.

A couple of bonus questions real quick:
- What's the best/most compatible DOS version to install on the ao486 core?
- Windows 3.11 or 95 OSR-2.5? And does launching DOS games from either impact performance in any significant way?
DevilHunterWolf
Posts: 102
Joined: Thu Aug 19, 2021 4:07 am
Has thanked: 2 times
Been thanked: 40 times

Re: SD card in second SD slot on I/O for ao486?

Unread post by DevilHunterWolf »

As far as I'm aware and just checked the wiki to try to verify, it doesn't look like the ao486 core uses that second slot. That microSD card slot is different, though. It's not a second microSD card slot in the normal sense. It's a card slot that gets direct wired to the core like how the User I/O USB slot is used for direct wiring original controllers to the cores using SNAC. A core has to be coded for that special connection. It otherwise just doesn't work as a standard microSD slot. To my knowledge, the only core that uses it is the Sharp X68000 core. I don't know of any other cores that use it.
Composite Lord
Posts: 6
Joined: Sat Oct 16, 2021 4:52 pm
Has thanked: 2 times

Re: SD card in second SD slot on I/O for ao486?

Unread post by Composite Lord »

Ah, I see, too bad really it can't double as a 2nd standard SD slot as I presumed. After having had a lot of bad experiences with typical SD cards and thumb-drives I've started using "high-endurance" SD cards made for always-on constant write camera duty and haven't had a single issue in years, only problem is they're typically not high capacity and fill quickly when we're moving into CD gaming libraries. I took a SanDisk High-Endurance 256gb card I had intended for something else and made it my new MiSTer drive, replacing my 128gb Samsung HE SD card I've been using, and put the top 300 eXoFlynn pack on there.

But to be honest the ao486 is surprisingly disappointing seeing as the other MiSTer cores kills any other form of emulation, ao486 has noticeably more input lag (even with 60hz sync set to variable) than both DOSbox and ScummVM running on Windows 10 and there seems to be mouse-acceleration (!?!?) on the core mouse driver making it personally unplayable for me. I don't know if this is because ao486 is more of a "hybrid" core than a "bit-perfect" preservation effort, but at this stage I'll be leaving it alone for now and freeing up a massive chunk of space on my SD card.

It's not all bad though, I've got a fresh MiSTer system install and a lot of extra space for all those PSX games it looks like we all will be installing sometime in the not to distant future thanks to FPGAzumSpass making progress on a project not thought possible by some at super-human speeds! :shock:
Bas
Top Contributor
Posts: 518
Joined: Fri Jan 22, 2021 4:36 pm
Has thanked: 60 times
Been thanked: 225 times

Re: SD card in second SD slot on I/O for ao486?

Unread post by Bas »

AO486 can hardly be made perfect because of the moving target it represents. There were large numbers of PC vendors all mixing all kinds of components and bus interfaces together with different BIOS'es as well as tweaked versions of DOS.

Interesting that you mention a mouse driver. The core certainly does not come with one. You can bring your own. Where did you get the VHD you're booting from?

I wouldn't know about the input lag as I play things like old Sierra titles, but quite a bit of that may be in the way your DOS software environment is set up.
Composite Lord
Posts: 6
Joined: Sat Oct 16, 2021 4:52 pm
Has thanked: 2 times

Re: SD card in second SD slot on I/O for ao486?

Unread post by Composite Lord »

When looking into the ao486 I saw Sorgelig say the ao486 is supported by scripts to function but a true 486DX recreation is fully possible on the MiSTer if only someone incredibly dedicated would take on the task of recreating it for FPGAs. True that the "IBM compatible" aspect of the hardware/software is (and was!) a challenge, but at this stage it's the WAY the core works that is the limiting factor. If we had a proper FPGA recreation of a specific Intel i486 CPU we could say "OK here is the reference, let's all build around this and configure things to work on this particular virtual 486 PC build", but again that would take A LOT of work and many probably feel DOSbox is a more convenient solution for now.

When I said "mouse driver" I meant it more like the way the core is setup to interpret mouse input rather than a driver that you'd install, I couldn't find any way to set anything about the mouse in the ao486 core and the feeling of mouse-acceleration was consistent across all games I tested. I got the eXoFlynn Top 300 VHD pack of the Archives, I'm not certain but I don't think the launcher adds universal mouse-acceleration to everything.

For the lag (and mouse-acceleration) it's really evident if you run for instance Indy Fate of Atlantis CD-Talkie on ScummVM and then run the same version of ao486, same with Dune (floppy) on DOSbox and then off ao486. I used the same mouse (Mamba Elite @1000hz) with the same stored onboard profile on the same channel on my LG B9 TV in game mode so it's the platform running the games that makes the difference. I have disabled "pointer precision" in Win10 and have set the Nvidia driver to "Vsync off" and "ultra low latency" so there is that if you want to compare yourself, but using the same settings and running WinUAE on the same setup then switching over to the MiSTer Amiga core using the same VHD, the MiSTer is absolutely more responsive and realistic feeling compared to my real Amiga 1200, the Amiga core does not have mouse-acceleration either and feels linear in response, so I don't think this is an inherent PS/2-to-USB interpretation issue.

Now, I'm not trying to badmouth the work that has gone into the ao486 core, I was just honestly surprised (and spoiled!) by the contrast to the other cores running realtime emulations to the point I can't feel the difference to real hardware. If anything though I'm perhaps a bit more skeptical to "hybrid" approaches and prefer it if cores stick to "pure" low-level FPGA implementations as much as possible. I still hope the ao486 core keeps getting worked on though, when it gets to the point the Amiga core is now, it'll already be the best way to play DOS games and preserved for the future.
Post Reply