Hi, I'm trying do drive WS2812B LEDs (aka neopixels) with the I2S peripheral, using method similar to this https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/posts/driving-ws2812b-leds-using-i2s-on-the-nordic-nrf52
I got the right signal out of SDOUT pin, provided I also configure LRCK and SCK pins (which I don't need). When I set either or both of the LRCK/SCK pins to 0xffffffff, no signal comes out of the SDOUT pin.
Is it possible to leave the SCK/LRCK disconnected and have the I2S still operate?
The code is below. It also has detects the end of transmission correctly (first TXPTRUPD triggers after the hardware picks up the pointer, so we set the MAXCNT to one more byte and wait for that one to be picked up).