Update:

Happy to report that the digital audio output now seems to work perfectly, thanks to a ton of help and patience from the guru of CS4237, 640K!enough! 🏆

While I'm waiting for parts and new prototypes, I'll do a thorough revamp of the BIOS settings menu, here's a preview:

The better this thing starts to look, the more ideas I get for making it even more elegant. An implementation idea that I like is using register X4 to detect the presence of the external FM module (activate external FM, set timer and busy-wait on the status word until expiry to confirm presence), and offering the option only if it responds. Otherwise, disable the option as "not present".

640K!enough wrote on 2023-08-10, 20:32:

The better this thing starts to look, the more ideas I get for making it even more elegant. An implementation idea that I like is using register X4 to detect the presence of the external FM module (activate external FM, set timer and busy-wait on the status word until expiry to confirm presence), and offering the option only if it responds. Otherwise, disable the option as "not present".

Ooh, I like that! 👍

Sooo amazing guys. Can I get a copy to test it on my hack (passing auto via HDMI?)
Also, can we have all these (or some of them at least) BIOS menus on the TL2 please? I love the TL2

@Eivind

Will you still have a PCI version of this board? or are you switching to AGP only?

ahmadexp wrote on 2023-08-11, 01:36:

Sooo amazing guys. Can I get a copy to test it on my hack (passing auto via HDMI?)
Also, can we have all these (or some of them at least) BIOS menus on the TL2 please? I love the TL2

I can take a look over the weekend, it's a bit more involved since the TinyLlama uses an eeprom with config data for the CS4237, whereas I'm loading this directly from the BIOS on the ITX-Llama. But we can probably hack something together. No guarantees it'll work with your SiL chip, though. But we can give it a shot! 😀
I won't port the new menus to the TL2 BIOS, as almost everything that's new only applies to the ITX-Llama.

Duffman wrote on 2023-08-11, 02:43:

@Eivind

Will you still have a PCI version of this board? or are you switching to AGP only?

I thought I'd switch to AGP only if it turns out to work as well as I'm hoping it will.... Do you object? 😉

@Eivind

For me personally I would like to use one of these chinese geforce FX 5500 cards that I got for $50AUD
They're PCI only though.
So I thought it might be a good idea to have on offer either AGP or PCI versions of the board.

Duffman wrote on 2023-08-11, 09:01:

@Eivind […]
Show full quote

@Eivind

For me personally I would like to use one of these chinese geforce FX 5500 cards that I got for $50AUD
They're PCI only though.
So I thought it might be a good idea to have on offer either AGP or PCI versions of the board.

Fair enough, I'll keep that in mind as I'm nearing completion in a few weeks!

I vote AGP!! Its so much easier to find good old 98 era AGP cards than PCI ones.

Hey there, I made this account just to be able to chime in... 😀

I LOVE this project and I am pro-AGP, for the selfish reason that I have a bunch of AGP cards that should work great with the Llamaboard. So when it becomes available I would be happy to buy one...

Update:
Still waiting for those illusive AGP ports to reach JLC for assembly... Meanwhile I've been completely rewriting most of my BIOS code (that goes on top of SeaBIOS, of course), complete with a menu system that'll make it soo much easier to modify later. PWM/Tach fan control are in place, working great. As are all other settings, afaik.
Haven't gotten to the external synth detection routine yet, but I think that's next now that the "boring" stuff is mostly done.

640K!enough: Here's your auto-detection idea implemented, working fine! 👍

Update:
Got the AGP connectors, more or less ready to order the next batch of prototypes.
I've swapped the CH559 (HIDman) with an RP2040 (Raspberry Pi Pico chip) in hopes of getting USB hub-connected HID devices working properly this time... 🤞

@Eivind, would you consider adding the changes for the wavetable? In ITX case things are much easier. We just need the DC2DC to provide the +/-12v and a jumper to switch between 3v3 and 5v Midi-in.

ahmadexp wrote on 2023-08-22, 05:39:

@Eivind, would you consider adding the changes for the wavetable? In ITX case things are much easier. We just need the DC2DC to provide the +/-12v and a jumper to switch between 3v3 and 5v Midi-in.

On the ITX board, I already have +/-12V to the wavetable header (from the ATX connector), and only the MIDI signal going to the Pi headers are voltage-divided down - the one going to the WT header isn't.

Eivind wrote on 2023-08-17, 16:10:

640K!enough: Here's your auto-detection idea implemented, working fine! 👍

Implementation was almost exactly what I described, I hope; no unpleasant surprises?

640K!enough wrote on 2023-08-24, 03:40:

Eivind wrote on 2023-08-17, 16:10:

640K!enough: Here's your auto-detection idea implemented, working fine! 👍

Implementation was almost exactly what I described, I hope; no unpleasant surprises?

Correct - I just enabled the external FM and ran the good old routine of setting up a timer on the OPL and reading back the status register. No unpleasant surprises! 😁

The AGP-equipped boards are finally in production - I had some helpful guidance from forum member sdz, who's previously made some very nice PCI-to-AGP adapters. Fingers crossed, I'll get this working as well!
In addition, this new revision has a different microcontroller (RP2040, as previously mentioned) for doing the USB HID to PS/2 translation, and a hopefully more robust way of dealing with PWM LEDs and HDD activity "clicker" based on the ATTiny84 and SD card data signals.
I also spent some time cleaning up the PCI/AGP signal routing and improved ground planes.

Update:
Just got the boards in, plopped on a Geforce4 Ti4200 AGP card, and got video! 🎉
Will do more tests and programming later today, but that was definitely a sigh-of-relief moment! 😀