Driving RGB LEDs with nRF52

[andrey]

In my case LEDs (N<10) would be animated (think pulsing).

My only concern is that the BLE core will limit the possibility to control the LEDs in real time, thus causing flickering and other artifacts. Perhaps DMA could help with that?

Has anyone had any experience with that?

[andrey]

WS2812B work fine with this port even with softdevice running. Glitch-free in connection mode with the loosest timing that iOS allows:

#define MIN_CONN_INTERVAL                MSEC_TO_UNITS(180, UNIT_1_25_MS)
#define MAX_CONN_INTERVAL                MSEC_TO_UNITS(200, UNIT_1_25_MS)
#define SLAVE_LATENCY                    4
#define CONN_SUP_TIMEOUT                 MSEC_TO_UNITS(5000, UNIT_10_MS) 

[Ole Bauck]

Nice, I have not seen this before.

I guess it uses the same principle as the one I linked to which uses PWM, but I don't see how using SPIM is better, either the timing will be incorrect or it will use much more RAM. I have not looked at exactly how it works, this is based on the description. Also it says: "It may not work with all WS2812B based array, because current version is not meet with the official spec". Do you know what he means about this? Is it that the timing is not correct?