This is an example program of WS2812 library https://developer.mbed.org/users/devararendy/code/WS2812/ in main program, i also put some line to measure how many asm NOP do we need. I have test it on STM32F411RE (Nucleo 411RE). if you would like to use another microcontroller, you need to adjust the asm("nop") in the library.

Dependencies:   USBDevice WS2812 mbed-os

no such method: tip