add() [2/8]

fl::ChannelPtr CFastLED::add ( const fl::ChannelConfig & config )

static

Add LED channel with runtime configuration (from ChannelConfig)

Creates and registers a Channel-based LED controller with runtime-configurable timing. Returns a shared_ptr for lifetime control - controller auto-removes on destruction.

Parameters

config

Channel configuration (pin, timing, leds, rgb order, settings)

Returns

Shared pointer to Channel (extends CLEDController), or nullptr if unsupported

Note

Supported platforms: ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6, ESP32-P4

Example:

auto timing = fl::makeTimingConfig<fl::TIMING_WS2812_800KHZ>();
fl::ChannelConfig config(PIN_DATA, timing, fl::span<CRGB>(leds, NUM_LEDS), RGB);
auto channel = FastLED.add(config);
fill_solid(leds, NUM_LEDS, CRGB::Red);
FastLED.show();
channel.reset();  // Destroy controller

Definition at line 616 of file FastLED.cpp.hpp.

                                                        {
    // Issue #2459: the non-template `FastLED.add(cfg)` path is the runtime-
    // selection mode. To make sure `cfg.options.mBus` (or priority dispatch
    // when `mBus == Bus::AUTO`) can actually find the requested driver at
    // runtime, we eagerly enroll every driver available on this platform.
    // That trades binary size for ergonomics — the user wanted runtime
    // selection, so they get runtime selection.
    //
    // For minimum binary size, callers should use the compile-time path:
    //   FastLED.addLeds<CHIPSET, PIN, ORDER, fl::Bus::X>(leds, n);
    // which ODR-uses only `BusTraits<X>::instancePtr()` and lets
    // `--gc-sections` drop every other driver TU.
    //
    // The warning fires at most once per process (FL_WARN_ONCE) and can be
    // disabled with `-DFASTLED_SUPPRESS_RUNTIME_DRIVER_WARNING`.
    #ifndef FASTLED_SUPPRESS_RUNTIME_DRIVER_WARNING
    FL_WARN_ONCE("FastLED.add(cfg): runtime-selection mode — enrolling every "
                 "available driver via fl::enableAllDrivers(). For minimum "
                 "binary size, prefer FastLED.addLeds<CHIPSET, PIN, ORDER, "
                 "fl::Bus::X>(leds, n) which links only the named driver. "
                 "Suppress this warning with -DFASTLED_SUPPRESS_RUNTIME_DRIVER_WARNING.");
    #endif
    fl::enableAllDrivers();
 
    fl::ChannelManager& manager = fl::channelManager();
    FL_ASSERT(manager.getDriverCount() > 0,
              "No channel drivers available - channel API requires at least one registered driver");
    auto channel = fl::Channel::create(config);
    add(channel);
    return channel;
}

References add(), fl::channelManager(), fl::enableAllDrivers(), FL_ASSERT, FL_WARN_ONCE, and fl::ChannelManager::getDriverCount().

Here is the call graph for this function: