Looks like in the future you should be able to squeeze it to half height pcb 😀

rasz_pl wrote on 2023-10-10, 20:42:

Looks like in the future you should be able to squeeze it to half height pcb 😀

You're right, it could be much smaller. The only reason the PCB is as tall as it is is to fit a maximum-sized wavetable card! It's strange laying it out with so much space.

how about rotating wavetable connector 180 to make it stick up instead of down, or even 90 and make it go sideways. I dont know exact dimensions of wavetable modules so no idea if sideways would work.

The max size is 138.430mm x 88.9mm, pretty big. Sideways definitely wouldn't work. Rotating 180 wouldn't be too bad, there are cards far longer than 138mm out there... but I think the current square-ish size is OK. Here is a photo of it compared to a v1.1 PicoGUS.

There's already a low profile (50mm tall) PicoGUS designed by Masteries, and it's also changed a bit to use SOICs that are more easily hand solderable.

polpo wrote on 2023-10-10, 07:29:

All boards will run the same firmware! There are some hardware differences on the new board that have to be handled, so the fir […]
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Shreddoc wrote on 2023-10-10, 01:35:

Will the v1.1 boards still be supported by ongoing future firmware releases?

or, to ask another way, will the v2.0 boards get features/functionality that the v1.1's cannot do?

All boards will run the same firmware! There are some hardware differences on the new board that have to be handled, so the firmware will detect that it's running on the board and adjust accordingly. Here's a breakdown of the differences:

PicoGUS v1.1/v1.1.1:
- Uses Pico or Pico W
- PCM5102 on module
- No wavetable header
- Micro USB-B port can be used for joysticks with powered USB OTG cable or a bodge, is internal to PC
- 3.5mm MIDI jack
I'm on the fence if I'll sell any of the v1.1.1 boards on Tindie - it's not much cheaper to make than 2.0, and people don't have to buy a Pico with 2.0. I'd say the only reason for me to sell these is to support the Pico W for future WiFi support (but it's inside the computer, so not the best for reception). I definitely want to keep this version 100% supported as it's the most DIY-friendly design, and that's important to me.

PicoGUS Femto w/ ISA adapter:
- Uses Pico or Pico W
- PCM5100 on board
- Wavetable header, analog volume thumbwheel for wavetable
- Micro USB-B port can be used for joysticks with powered USB OTG cable or a bodge (or jumper in next batch), is external to PC
- 2.5mm MIDI jack
I'll be putting some more of the Femto in my Tindie shop soon. I got the PCBs today but I still need to assemble the connectors on them.

PicoGUS v2.0:
- RP2040 direct on board
- PCM5100 on board
- Wavetable header, digital volume control for wavetable (set with pgusinit.exe)
- USB-A port so joysticks (or mice, or whatever else) can just plug in
- 3.5mm MIDI jack
The main reason for the digital volume control is that JLCPCB stopped carrying the analog thumbwheel I was using, and the digital one is a lot cheaper than a physical control. I asked a bit about this a few posts above. The goal of this version is to make something 100% able to be assembled by JLCPCB. I got the first prototype today and got it working in GUS mode tonight... I need to tweak a couple things but I think it's ready to be "mass produced" once the parts arrive at JLCPCB.

fac3a54da98a8732.jpeg

Thank you for the detailed and informative response. It is heartening to know that my early DIY builds will stay supported.

It is so cool to see the community recognition of the PicoGUS project growing over time. It turns out, that the answer to the question I've been asking myself for the past 16+ months - "why, the heck, is everybody not ALL OVER this awesome thing???" - is "just wait.... and they will come". 😀

Polpo,

I stumbled upon this project after seeing Adrian's video on it and have been looking into building one. I apologize if you already are aware of this, but I wanted to share how I had some HardMPU boards made up at JLCPCB.

On your github you mention the following regarding the board options:

Surface finish: HASL w/ lead. I've heard both ways about whether HASL or ENIG card edge connectors last longer. ENIG won't corrode, but is an extremely thin surface. HASL is thicker and can possibly take more wear. Hard gold is better than both, but is not an option at JLCPCB, and is expensive at fabricators that do offer it like PCBW

I'd recommend building the boards with the ENIG finish, +Gold Fingers, and the 30 degree chamfer on the edge. https://jlcpcb.com/quote/pcbOrderFaq/Gold%20Fingers. My HardMPUs have held up very well inserting and removing them and that finish makes for very resilient contacts and easy insertion in/out of an ISA slot. Choosing the gold fingers option I believe creates a more resiliant edge connector than just choosing ENIG alone (which like you said is very thin).

It increases the setup cost of a run of boards, but if you order them in any quantity, the overall cost difference evens out.

Shreddoc wrote on 2023-10-10, 21:12:

It is so cool to see the community recognition of the PicoGUS project growing over time. It turns out, that the answer to the question I've been asking myself for the past 16+ months - "why, the heck, is everybody not ALL OVER this awesome thing???" - is "just wait.... and they will come". 😀

I still have the same feeling for PicoMEM 😀
But it is yet not available for self build and not published.

I'm proud to have been here since Day 1 😁

Has anyone tried picogus on Micro8088 designed by Sergey Kiselev?

Thank you for this project!
Just received this card from Tindie (not from the original author, at the time of order only two from Sweden were available)
It's just great 😀
Fully working in my Pentium MMX, tested with Second Reality, NoooN: Stars and Gravis MIDI demo, of course.
Sound is maybe even too clean, some instruments are a bit more noticable and overall spectrum is a bit on high side, but it's awesome as it is.
If it would have SBPro/16 support and a couple of line-ins i would ditch my SB16 😀
For some reason pgusinit didn't regognize it in ISA extender on Book8088 and Hand386, but it might be my luck and ISA extender is bad.
Thanks again!

n0p wrote on 2023-10-22, 19:49:

Thank you for this project! Just received this card from Tindie (not from the original author, at the time of order only two fro […]
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Thank you for this project!
Just received this card from Tindie (not from the original author, at the time of order only two from Sweden were available)
It's just great 😀
Fully working in my Pentium MMX, tested with Second Reality, NoooN: Stars and Gravis MIDI demo, of course.
Sound is maybe even too clean, some instruments are a bit more noticable and overall spectrum is a bit on high side, but it's awesome as it is.
If it would have SBPro/16 support and a couple of line-ins i would ditch my SB16 😀
For some reason pgusinit didn't regognize it in ISA extender on Book8088 and Hand386, but it might be my luck and ISA extender is bad.
Thanks again!

Thank you for the feedback! About not working on the Book8088 and Hand386, the reset line on those machines is very noisy/glitchy and causes the PicoGUS to constantly reset itself. There are fixes in the "Femto Edition" that work around those issues: instead of a 74LVC14 I am using a 74AHC14 which has a slightly higher logic high input voltage theshold, and also I add a pull down resistor on the reset line. And if those fixes are not sufficient (though in my testing with my own Hand386, they are), I added a jumper to completely ignore the reset signal.

polpo wrote on 2023-10-22, 21:35:

I added a jumper to completely ignore the reset signal.

Thanks!
Do i get it right that a paper insulation on pin B2 would work?

As a hail mary, I actually succesfully fixed the issue on mine with a 100nF cap (a through-hole one with legs) between the RUN and GND pin of the pico itself (should be 28 and 30), after I saw the pico reset itself mentioning the RUN pin as the reason (but not really seeing actual drops or huge noise on the pin with an oscilloscope). It's been fully stable here since then.
Maybe that might be a fix for you also, but caveat emptor, of course 😉

MJay99 wrote on 2023-10-23, 09:54:

As a hail mary, I actually succesfully fixed the issue on mine with a 100nF cap (a through-hole one with legs) between the RUN and GND pin of the pico itself (should be 28 and 30), after I saw the pico reset itself mentioning the RUN pin as the reason (but not really seeing actual drops or huge noise on the pin with an oscilloscope). It's been fully stable here since then.
Maybe that might be a fix for you also, but caveat emptor, of course 😉

Thank you! Could you share the photo of the fix, any quality? I'm bit on software side tbh, just to make sure i did that right.

MJay99 wrote on 2023-10-23, 09:54:

As a hail mary, I actually succesfully fixed the issue on mine with a 100nF cap (a through-hole one with legs) between the RUN and GND pin of the pico itself (should be 28 and 30), after I saw the pico reset itself mentioning the RUN pin as the reason (but not really seeing actual drops or huge noise on the pin with an oscilloscope). It's been fully stable here since then.
Maybe that might be a fix for you also, but caveat emptor, of course 😉

Interesting! And yeah, I never ever saw any glitches on my scope on the RUN pin when the Pico resets. Apparently that pin on the Pico is extremely sensitive. Adding a cap is an interesting idea, I might be stealing that for a future hardware revision to augment the fixes I have already...

Hi all,
I think that my problem with Micro 8088 is the reset too. According the log from card, picogus pass out in bootloop.
I tried sevral workarounds.

#1 Office paper tape.
Just use the tape on RESET signal and Picogus alives in my machine

#2 Filter capacitor 100nf - place A
Nice place but doesn't work for me - Picogus boot propertly but pgusinit doesn't see the card

#3 Filter capacitor 100nf - place B
Probably my final solution.

n0p wrote on 2023-10-23, 11:44:

Thank you! Could you share the photo of the fix, any quality? I'm bit on software side tbh, just to make sure i did that right.

Sorry for the delay - here is the picture of what fixed my card (don't bother about the rest of the layout, I played and tested a bit with different routings and some amalgamation).
Very interesting that only putting it on U5 has fixed it for DPRCZ. So, if you can, please report back what fixed it for you 😉

@DPRCZ, @Mjay99, @polpo - thank you guys! Will test those fixes asap.
Just a quick question - does capacitor has to be exactly 100nF? There's some problem getting parts locally, so it would be great to know possible range.

I am using it in a 486 without issues, I wonder if I should add the cap as well, you know, just in case..

appiah4 wrote on 2023-10-24, 08:22:

I am using it in a 486 without issues, I wonder if I should add the cap as well, you know, just in case..

If you ask me: If it works, it works... it was really just a hail mary attempt of mine, after it kept resetting itself consistently after a few seconds while I wasn't even seeing anything remotely actionable on the oscilloscope.

So, if you happen to find it keeps stopping to play after a very short time or not playing much at all, it's very much worth a try, even more if you are connected to the midi/debug port and it's telling you it's been reset by the RUN pin.
Otherwise, I'd say: no need to botch it in and make the card a little less beautiful 😀