Installing the Keyboard OS firmware

PicoCalc
1

Hi, I’m trying to upgrade the keyboard firmware on my recently received (end Nov 2025) PicoCalc and can’t get it to upload from my Windows 11 machine. I seem to get keypresses missed if I type, maybe quickly hence the thought that an upgrade will fix this.

Firstly, do I need to upgrade? Is there a way for me to figure out what firmware I currently have installed.

Secondly, when I follow the instructions here: Setting Up Arduino Development for PicoCalc keyboard · clockworkpi/PicoCalc Wiki · GitHub I cant get the PicoCalc to connect via a usb port as described. Sometimes the PicoCalc led light and or flashes and I get a Com8 vissible, but most times I don’t. When I get a Com8 the upload from Arduino fails with an error STMCubeProgrammer.

So, are the instructions operable on Windows11? How do I realiably get the PicoCalc to connect over USB? Do I actually need to update?

Thanks

2

No, it’s a known physical problem with the rubber key pad, so a firmware update isn’t going to help. You just have to push harder.

I’ve seen a couple of references to people putting a sheet of paper between the rubber and the pcb to increase the key preload, but I’ve not personally tried it.

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i genuinely think the problem is threefold:

  • the physical switches (the interaction between the rubber and the clicky switches, which themselves are not great since the click feedback is not 100% of the time in sync with there being an actual closed electrical connection)
  • the keyboard firmware (i have not used the official firmware beyond like day 2, in my experience Jack Carter Smith’s works a lot better with optimisations)
  • whatever software you use not handling the keyboard FIFO robustly enough to avoid dropped keys, or worse, buffering keys in a way that you get old key presses instead (this happened on my own firmwares until i implemented some fixes)

with proper keyboard firmware, and pico software that handles the I2C better, i have noticed a significant decrease in typing issues. that does not mean it fixes the physical issues with the keyboard switches which also cause drops

that said, i can’t speak to your issues upgrading the firmware, sorry

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Do you have a link to Jack Carter Smiths firmware please?

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I’m confused about which keyboard firmware to use.

There is Jack’s version as above, and this 1.4 version.

Does one replace the other? I can’t find the precompiled download for Jack’s version. Is that available?

Thank you for clarifying this…..Brian

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I must admit it would be very nice for the newbies of which I consider myself one, to have a step-by-step menu on updating the pico, Kal keyboard and firmware.

I have always done this for anything I’ve beta tested at HP and for third-party manufacturers, such as Systemyde.

Geoff

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This should help:

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1.2 and 1.4 is the official supplied by ClockworkPi. JCS made a custom one which uses the chip completely differently but is compatible as far as the Pico is concerned.

Yes, they all get uploaded to the same chip in the PicoCalc motherboard (NOT the Pico)

“Releases” at the top of the page… Making sure you're not a bot!

i found the steps in the readme for JCS’s firmware to be as step by step as possible, are those not clear enough? Making sure you're not a bot!

also, note that those steps can be used with any BIN file made for the keyboard chip, not only JCS. so you can follow those instructions with the official BIN too

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