Second WS* strand not working?

[HumanDactyl]

Hey all.  Super new falcon pi-hat user here.  Wired it up and have no problem getting D18 working, but D19 gives the following error:

RuntimeError: ws2811_init failed with code -11 (Selected GPIO not possible)

What am I doing wrong? Thanks!

[CaptainMurdoch]

Which model Pi is this and do you have any GPIO configured for anything else like a button input?

[HumanDactyl]

PI 4, only the two pixel strands.

[HumanDactyl]

To give more data, I'm not yet running a supplied FPP image. I've tried two things:

1/ Running a PI4 with no FPP image.  Pin 18 works fine, Pin 19 errors out
2/ Running a PI4 with a FPP image.  I cannot get it to connect to wifi so I can configure it like I've seen tutorials do.

So I suppose I need solve one of the two problems - which? Thank you!

[Poporacer]

1/ Running a PI4 with no FPP image.  Pin 18 works fine, Pin 19 errors out

If you don't have FPP installed, what operating system are you running and can you show a screenshot of this error? (not a picture of the screen please)

Running a PI4 with a FPP image.  I cannot get it to connect to wifi so I can configure it like I've seen tutorials do.

I am not sure what tutorial you are using, or how you are trying to configure your Wi-Fi. This might help?

[HumanDactyl]

Here's screenshots. I'm running headless, so best I can do.

[tbone321]

Most of the people here are familiar with configurations in FPP, not programming in Python.  Without seeing the source code, the error is indicating that the GPIO is not configured for what you are attempting to use it for.  Many of the GPIO pins are dual use and if not configured for GPIO, will not function that way.  FPP will configure the GPIO ports it is using properly but in Python, you have to do it.  I would look at the vid that Poporacer sent you and configure FPP.

[HumanDactyl]

After config with fpp, can I still just write GPIO python standard stuff?  I am not running a light show, but I love the board.  I'm running something much slower.

[HumanDactyl]

Okay, watching the video I can get both strands working through the test tool, but I'm not sure I'm on the right track to doing what I want.  Some people in my LED group told me to get this device to easily control two strands... I am not making a show, but a warehouse inventory system - so at any time, I need to light up very specific LEDs.  Can I do that with this hat?  Or is it really just for running shows while tethered?  I was hoping I could just configure the pins, then write my own python server to control the strands.

[HumanDactyl]

Most of the people here are familiar with configurations in FPP, not programming in Python.  Without seeing the source code, the error is indicating that the GPIO is not configured for what you are attempting to use it for.  Many of the GPIO pins are dual use and if not configured for GPIO, will not function that way.  FPP will configure the GPIO ports it is using properly but in Python, you have to do it.  I would look at the vid that Poporacer sent you and configure FPP.

Do you know a tutorial for how I can configure the extra pins for GPIO?  This seems like the right path for me.

[MikeKrebs]

This video does two strips at one time.


Doesn't appear to line up the GPIO from the picap with what he talks about in this video but it should let you do your project.

[HumanDactyl]

Thanks, I'll check it out.  I liked the no-solder lifestyle of using the PiHat