I wrote a little Arduino sketch to create a smoldering fire effect with orange LEDs for my Hudson firebox. I stuck it up on github in case it’s useful to anyone.
https://github.com/ereuter/smolder
It generates a random brightness and a random amount of time to ramp to it, and then picks a new brightness and interval, and on and on. The code is non-blocking, so you can do other things with the Arduino and just call it in the loop.
