Hello FastLED Community! I stumpled over FastLED and tried it with the WS8XXX LED's

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Hello FastLED Community!

I stumpled over FastLED and tried it with the WS8XXX LED’s (and it’s awesome!).
I have a few questions and I hope someone could answer them:

  1. Is there are particular reason why the simple shift register types aren’t supported any more? I’m considering using it with the TLC5916 which is a simple shift register.
  2. I looked at the code and I’m not sure where and how to implement the backend? I could implement a TLC5916 backend myself in normal code, but the FastLED library could provide a good abstraction for timing and SPI.

Thanks for reading!

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Simple shift register types aren’t supported anymore because they require the PWM to be managed on the MCU side which requires all sorts of irritating timer games to be played. Note, that *595 chips are “simple shift register” types. The TCL5916 isn’t a simple shift register, as it drives the PWM in chip, like the WS2801 or LPD8806.

The TLC5916 and friends weren’t ever supported. They’re on the list for me to add support for eventually, but between a more convoluted control structure, and the fact that most people using the library (and the projects they tend to get used for) are using more common chipsets like the WS2801, LPD8806, WS2811/12, and hopefully soon the APA102, there hasn’t been a lot of push to get it supported. (In fact, you may be the 3rd or 4th person to ask for it. Ever.)

I have the hardware here to do support for it - I just also have a backlog of other work that needs to be done with the library and disturbingly little time period these days.

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Thanks for the honest words! You are right, the TLC59* do need “irritating timer games”.
Hm, maybe I’ll use the CRGB structures and the utility functions and try to write a driver outside the FastLED structure…
I can totally understand that timer mangling is not nice if no one uses that chips.

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The tlc5916s do their own pwm which means they aren’t simple shift registers (and as such, weren’t ever supported by the livrary)

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Are you really sure? I’ve got one here … the only thing you can adjust is a common current gain - which is no PWM “just” a current limit. http://www.ti.com/lit/ds/symlink/tlc5917.pdf

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Ah - sorry about that - I was thinking of a different set of tlc chips which do their own pwm - and saw a 256 level reference in the datasheet, so I conflated the two.

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Which ones do you mean - maybe these are a good alternative for me?