WS2812B on SPI1 behaves different than on SPI0

Describe the bug

When trying to run the sample from the repo with using SPI1 (GPIO 20) instead of SPI0 (GPIO 10), the strip lights up as almost completely white. A hint of color can be seen (red becomes a very light pink) can be noticed, as well as changes when using the TheatreChase. But when using e.g. Black in ColorSwipe, the strip becomes white.

Because we need to use SPI0 for another device, we need to switch to SPI1. Alternatively, an implementation with PWM would possibly work.

Steps to reproduce Enable spi1 by adding

dtoverlay=spi1-1cs

to /boot/config.txt and reboot.

Then change

SpiConnectionSettings settings = new(0, 0)

to

SpiConnectionSettings settings = new(1, 0)

and run the code

Expected behavior

The strip color should be the same when using either SPI0 or SPI1.

Actual behavior

The color is almost completely white when using SPI1.

Versions used

• dotnet --info on the machine being used to build: 5.0.401
• dotnet --info on the machine where app is being run: 5.0.400
• Version of System.Device.Gpio package: 1.5.0
• Version of Iot.Device.Bindings package (not needed if bug is in System.Device.Gpio): 1.5.0

[OJapes]

“-3cs” just enables more chip select lines. For WS2812B none is needed, so I’d like to keep it as low as possible. Anyway I’ve tested that and it doesn’t make difference.

It also seems that the SPI itself is enabled correctly because the “Animation” is perceptible.

UART is disabled.

[msftbot[bot]]

This issue has been automatically marked as stale because it has been marked as requiring author feedback but has not had any activity for 4 days. It will be closed if no further activity occurs within 3 days of this comment.