ESP8266 flickers a bit when using IR interrupt, but https://github.com/JoDaNl/esp8266_ws2812_i2s/ works

[marcmerlin]

This is not a bug, just documentation for others.
When I use fastled on ESP8266, it works, but from time to time I get slight flickering when the infrared timer is active (while on teensy 3.1 it does not). I'm going to guess the IR handler is just a bit slower or less time bound on ESP8266 and causes the occasional timing glitches.

Probably nothing anyone can do with the current design (the fastled driver nicely re-enables interrupts which allow the IR handler to run), however if anyone hits this problem, there is a better solution:
https://github.com/JoDaNl/esp8266_ws2812_i2s/
This driver (ab)uses the I2S support in the chip to drive neopixels without tying up the CPU. It's not even close to having the features that FastLED has (or the same amount of LEDs supported), but for neopixels, it works and I can run my interrupt at the same time without any issues or glitches.

This issue is mostly there to serve as documentation if someone needs IR + neopixel on ESP8266.

If anyone cares, this is my fastled version.

In file included from /home/merlin/Arduino/prg/Neopixel/Neopixel-IR/Neopixel-IR.ino:33:0:
/home/merlin/Arduino/libraries/FastLED/FastLED.h:17:21: note: #pragma message: FastLED version 3.001.003
 #    pragma message "FastLED version 3.001.003"
                     ^
In file included from /home/merlin/Arduino/libraries/FastLED/FastLED.h:65:0,
                 from /home/merlin/Arduino/prg/Neopixel/Neopixel-IR/Neopixel-IR.ino:33:
/home/merlin/Arduino/libraries/FastLED/fastspi.h:110:23: note: #pragma message: No hardware SPI pins defined.  All SPI access will default to bitbanged output
 #      pragma message "No hardware SPI pins defined.  All SPI access will default to bitbanged output"

[marcmerlin]

This page and video explain the issues between IR and neopixels, and how to make it work on teensy v3.1, ESP8266, and ESP32:
http://marc.merlins.org/perso/arduino/post_2017-04-03_Arduino-328P-Uno-Teensy3_1-ESP8266-ESP32-IR-and-Neopixels.html
this short video shows how trying this on AVR is an exercise in frustration and handling failures :)
https://www.youtube.com/watch?v=62-nEJtm070