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Oliv4945 / wipy-WS2812

Wipy driver for WS2812 RGB LEDs (WS2812B, AdaFruit NeoPixels, ...).
MIT License
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WiPy time between 8-bit SPI transfers. #6

Open ghost opened 6 years ago

ghost commented 6 years ago

Thanks for posting this code. I have done something similar, but I'm finding that it takes the WiPy much longer than 2 cycles between transactions. You wrote this (below), but when I actually look at the data pin of the WiPy 2.0, there are 3.45 us between each 8-bit SPI transfer.

Bus 0, 8MHz => 125 ns by bit, 8 clock cycle when bit transfert+2 clock cycle between each transfert => 125*10=1.25 us required by WS2812

ghost commented 6 years ago

I should add my code still works, but I was just wondering where this 2-cycle assumption comes from.

Oliv4945 commented 6 years ago

I think it was from WiPy/TI CC3200 documentation but I do not remember, sorry