On ESP platforms the dev kit provides the function __cxa_pure_virtual, so there is no need to define it.

for chipsets that need it (for example TM1829)

Suggested by @h3ndrik : allocated the interrupt once at the initialization and then just turn it on and off. This is the strategy that the ESP32 core uses also.

Two major changes to the RMT driver. First, I realized that we can have only one interrupt handler attached to the RMT peripheral, so it needs to be able to handle all of the attached strips. To accomplish this, I store each ClocklessController in an array indexed by its RMT channel. The interrupt handler can then take the channel that triggered it and index into the array to get the right controller.

The second major change is that I replaced all of the explicit bit twiddling of the RMT configurartion with calls to the proper functions in ESP32 core. That should make the code more stable if the core changes.

Since the interrupt handler is global for all channels, we need to store not just the controller, but also the buffer refill function for each strip.

This version of DemoReel100 spins off a separate task on core 0 that just performs the FastLED.show() operations. Regular code running on core 1 (the default for Arduino) signals this task to request a show().

Replaced a 500ms delay in the show task with MAX_DELAY. There's really no point in timing out (and crashing the program) just because the application hasn't called show.

Reworked the code again in order to support parallel output, which is now the default mode. You can also now ask it to use the built-in RMT driver if you have other parts of your code that need the RMT peripheral.

Two #defines control choices -- put either or both of these before including FastLED.h:

#define FASTLED_RMT_CORE_DRIVER

Uses the ESP core RMT driver. To do this, though, it allocates a big buffer to hold all of the pixel bits, so there is a memory and compute cost.

#define FASTLED_RMT_SERIAL_OUTPUT

Force serial output of each strip.

Describing the implementation and the compile-time switches

The previous checkin had bugs in the syncronization that caused problems in parallel mode when strips are different lengths.

Made the code bullet-proof in a few ways, but most importantly fixed a terrible integer underflow bug in the code that fills the RMT buffer.

The big change in this version is the ability to support more than 8 controllers. Instead of assigning RMT channels to controllers in a fixed mapping, channels are assigned on the fly, allowing the driver to reuse channels as they become available.

Didn't mean to check these in.

Fixed the code so that it works with the built-in RMT driver. There's nothing special to do to enable it -- just #define FASTLED_RMT_BUILTIN_DRIVER true

Fixing some documentation and configuration stuff