Picade xhat hackheader + Neopixels

Been messing about with the picade xhat and its hack header and experimenting with the pin outs to power and run a small number of neo pixels, looking at the pinout diagram for the xhat i figured i could use GPIO Pin 14 and change the python code that runs the neo pixel data from the default pin 18 and let it know its using GPIO pin 14.

Ive been following the neopixel guide and the site says that you must plug data into GPIO10, GPIO12, GPIO18 or GPIO21 for neopixels to work? these are all being used by the picade xhat at the moment.

Has anyone used the hack header for neo pixels and got it to work cant seem to find any examples or guides for this online or am i best just getting a pico board to power my Neo pixels and and ignoring the hack header.

What I did was
sudo nano /etc/systemd/system/plasma.service
and changed the -o GPIO:14:15 to -o GPIO:23:24 for my Blinkt. You can as far as i know use what ever pin you want as long as nothing esle is also using it.

And then I did
sudo nano /usr/bin/plasma
and changed LIGHTS = 10 to LIGHTS = 2 for my Blinkt. 2 actually equates to 4 LEDs as each Plasma Button has I believe 4 LED’s
It you want to change the pattern look for a line with load_pattern(“default”) at the end.
I changed it to load_pattern(“trippy”) and it switched.

Also, I did the above on a stock Raspberry Pi that didn’t have a Picade Hat on it. All I did was install the Plasma software and modify the config to work with the pins used by my Blinkt. I also had it working on the one LED on my Fan Shim. It was by accident but it worked.

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I’m sure you know this but I’ll post it for anybody else that may read this thread.

To install plasma its
curl https://get.pimoroni.com/plasma | bash
And to install the plasma daemon its
cd plasma
cd daemon
sudo ./install.sh
To turn it off its
sudo systemctl stop plasma
sudo systemctl disable plasma
And to re enable it its
sudo systemctl enable plasma
sudo systemctl start plasma

Thanks tried the above and a number of things to get it working with plasma last night but after a good few hours of tinkering it just refuses to light up. I trawled here and elsewhere for examples or guides of others using the hack header and I’m coming up blank.

Im new to pi so maybe this is a bit too much of a complex thing to do as a first project. their is pretty much zero documentations and guides out their on the hack header so its not as if i even have any reference to look up.

I’m really tempted to just scrap using the hack header and run my pixels off a pico instead as their are loads of guides on how to run neo pixels on these and i know id have it up and running with minimal fuss in no time.

As far as I know the you are supposed to use the BTN 7 and 8 pins. They go to GPIO 14 and 15. Which is what the Plasma header is wired too.
Picade X HAT at Raspberry Pi GPIO Pinout

Yeah plasma is set these as default so didn’t have to change them looking at the picade pinout diagram btn7 goes to 14 and btn8 goes to 15 so at a loss to why its not working.

Try swapping the clock and data, instead of 14,15 go 15,14. Switch the jumpers on the BTN 7 and BTN 8 pins.

This may be a stupid question, i have 3 pins coming from my neopixel stick, ground, 5v power and Data, there is no clock? is this needed for neopixel.

No, not needed, just move the data to the other pin.

EDIT: I didn’t think it was needed, but now I’m not so sure? I thought my fan Shim only had the one Data pin but after double checking I see it has Data and Clock, so now I’m not so sure? Maybe that is why you can’t get it to work?

Something else to keep in mind is you don’t have to use Plasma. You could use something more suited to Neopixels. Your not locked into using Plasma just because its a Picade X Hat. Your not actually using anything other than the extension of a pin from the Pi’s GPIO header.

I didn’t managed to get the hack header working but picked up a rasberry pi pico which is like £3-4 and got it all up and running pretty much straight away, for people new to pi this was a lot simpler way to program the leds and far less of a headache.

Its always nice to have alternatives. I’m hoping to do some PICO stuff over the weekend. Just have to find my round 2it. ;)