I’m looking for FastLED alternatives for Raspberry Pi. If anyone happens to know, please share!
I just got a fadecandy – plugged it in this morning and WOW this thing is cool. Might be a tiny bit of a learning curve but it apparently works great with Raspberry Pi: https://learn.adafruit.com/1500-neopixel-led-curtain-with-raspberry-pi-fadecandy/overview
Best approach today seems to be what Erin said: external hardware between the RPi and the LED strips. FadeCandy is great for this.
Adafruit has some notes on it and how to DIY. https://learn.adafruit.com/neopixels-on-raspberry-pi/overview
Thanks for the info about Fadecandy! Will try it on later. I’m running out of time to build Halloween costume for my daughter, so I went for Gertduino stacked on top of the RPi. The Gertduino is handling FastLED, Ping sensor while RPi is taking care of the sounds.
@Mark_Kriegsman Hey, can you explain why the RPi can’t control the LEDs directly? (as opposed to an Arduino)
The Adafruit page alludes to it but the short version is that the WS2811 / WS2812 “Neopixel” LEDs are so sensitive to exact signal timing that the transmission of each pixel’s data cannot be disrupted, or it doesn’t work. And any time you have a ‘real’ operating system, code is always being interrupted for something or other-- thousands of times a second. And the RPi runs an operating system. In theory, someone could write a kernel module that disabled interrupts while signaling data to the LEDs, as FastLED does for each pixel on Arduino, and that might work – presuming the rest of the OS doesn’t get cranky about having interrupts disabled so much.
Alternatives are simple: have the RPi drive a microcontroller with NO O.S., eg an Arduino, or use LEDs which aren’t so twitchy about precise timing (eg APA102, LPD8806).
@Mark_Kriegsman Thanks for the detailed answer!