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From: Jeroen Belleman <jeroen@nospam.please>
Newsgroups: sci.electronics.design
Subject: Re: Positional/physical addressing
Date: Wed, 25 Jun 2025 23:29:08 +0200
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On 6/25/25 19:30, Ian wrote:
> On 2025-06-24, Jeroen Belleman <jeroen@nospam.please> wrote:
>> WS2812 LED chips do something like that. The first chip in the chain
>> absorbs the first three bytes and passes on all that come after, and
>> so on down the chain. Wait 50 us and the first chip in the chain is
>> ready again to intercept its three bytes.
> 
> That's not quite how they work. The whole chain is one big shift register,
> (24 bits per device), with 1's and zero's being shifted along as broad
> or narrow pulses. When the pulses stop for a while*, the 24 bits sitting
> in the "shift register" are latched into the "DAC register" and the
> colour changes.

Read the datasheet.

Jeroen Belleman