Driving the RGB LED in Arduino

Hardware Robot Hardware
1

I’m using the Adafruit NeoPixel Library (v1.12.5) in Arduino (v2.3.6) with the Earl Philhower Arduino-Pico Core (v4.5.3) to test the RGB LED on the XRP Controller.

Using the “buttoncycler.ino” example sketch, I am unable to see any RGB LED activity, using RGB Pin setting = 37 and Button Pin setting = 36. When I test using an external NeoPixel connected to GPIO pin 19, it works!

I also tried to get the basic Arduino “blink” example sketch to work with a regular LED circuit attached to GPIO37, with no success.

Please advise. Thank you.

Dennis

2

Hi there,

Looks like the problem is with the Adafruit NeoPixel library not setting the PIO base correctly for GPIO 32-47. I’ve submitted an issue here: Support for RP2350B (GPIO 32-47) · Issue #434 · adafruit/Adafruit_NeoPixel · GitHub

I would suggest FastLED, but that has a similar problem. I’ve submitted an issue there as well: Support for RP2350B (GPIO 30-47) · Issue #1925 · FastLED/FastLED · GitHub

There are a number of other Arduino libraries for driving NeoPixels (WS2812), though I’m not familiar with any of them and whether they have support for the higher pins on the RP2350B. You can try some other libraries to see if they work, or wait for either Adafruit’s NeoPixel or FastLED libraries to get an update to resolve the problem.

Hope this helps!

3

Thanks for the quick review! I’ll keep my eyes open for these library updates.

-Dennis

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