Removes legacy RMT, adds brightness + RGBW support

CMakeLists.txt

@@ -20,7 +20,7 @@
 
 set(ATOMVM_NEOPIXEL_COMPONENT_SRCS
     "nifs/atomvm_neopixel.c"
-    "nifs/led_strip_rmt_ws2812.c"
+    "nifs/led_strip_driver.c"
 )
 
 # WHOLE_ARCHIVE option is supported only with esp-idf 5.x
@@ -34,7 +34,7 @@ endif()
 idf_component_register(
     SRCS ${ATOMVM_NEOPIXEL_COMPONENT_SRCS}
     INCLUDE_DIRS "nifs/include"
-    PRIV_REQUIRES "libatomvm" "avm_sys" "driver"
+    PRIV_REQUIRES "libatomvm" "avm_sys" "driver" "led_strip"
     ${OPTIONAL_WHOLE_ARCHIVE}
 )
 

Kconfig

@@ -5,5 +5,41 @@ config AVM_NEOPIXEL_ENABLE
 	default y
 	help
 		Use this parameter to enable or disable the AtomVM NEOPIXEL driver.
+
+		This driver uses the ESP-IDF led_strip component which provides:
+		- Automatic DMA support on ESP32-S3/C6
+		- SPI backend fallback for better WiFi coexistence
+		- Maintained by Espressif for optimal performance
+
+choice AVM_NEOPIXEL_BACKEND
+	prompt "LED strip backend"
+	default AVM_NEOPIXEL_BACKEND_AUTO
+	depends on AVM_NEOPIXEL_ENABLE
+	help
+		Select the backend peripheral for driving the LED strip.
+
+config AVM_NEOPIXEL_BACKEND_AUTO
+	bool "Auto (recommended)"
+	help
+		Automatically select the best backend for your chip:
+		- ESP32: SPI with DMA (best WiFi coexistence)
+		- ESP32-S3/C6/P4: RMT with DMA
+		- Others: RMT, fallback to SPI
+
+config AVM_NEOPIXEL_BACKEND_SPI
+	bool "Force SPI"
+	help
+		Always use SPI backend with DMA.
+		Best for WiFi coexistence on all chips.
+		Note: Uses entire SPI bus (SPI2_HOST).
+
+config AVM_NEOPIXEL_BACKEND_RMT
+	bool "Force RMT"
+	help
+		Always use RMT backend.
+		May cause flickering with WiFi on ESP32 (no DMA).
+		Works well on ESP32-S3/C6/P4 with DMA.
+
+endchoice
 
 endmenu

README.md

@@ -1,6 +1,15 @@
 # AtomVM NeoPixel Library
 
-This AtomVM Erlang library and Nif can be used to control WS2812 LED strips using the ESP32 SoC for any Erlang/Elixir programs targeted for AtomVM on the ESP32 platform.
+This AtomVM Erlang library and Nif can be used to control WS2812 and SK6812 LED strips using the ESP32 SoC for any Erlang/Elixir programs targeted for AtomVM on the ESP32 platform.
+
+## Features
+
+- **RGB LED support** (WS2812, WS2812B) - 24-bit color
+- **RGBW LED support** (SK6812) - 32-bit color with dedicated white channel
+- **Global brightness control** - Hardware-efficient brightness scaling (0-255)
+- **Multiple color spaces** - RGB, RGBW, HSV, and HSVW
+- **Batch operations** - Fill entire strip or set multiple pixels in a single call
+- **ESP-IDF 5.x compatible** - Uses the new RMT driver API
 
 This Nif is included as an add-on to the AtomVM base image.  In order to use this Nif in your AtomVM program, you must be able to build the AtomVM virtual machine, which in turn requires installation of the Espressif IDF SDK and tool chain.
 

examples/neopixel_example/src/neopixel_example.erl

@@ -16,14 +16,15 @@
 %%
 -module(neopixel_example).
 
--export([start/0]).
+-export([start/0, demo_fill/0, demo_pattern/0]).
 
 -define(NEOPIXEL_PIN, 18).
 -define(NUM_PIXELS, 4).
 
 -define(SATURATION, 100).
 -define(VALUE, 15).
 
+%% @doc Main example - rainbow cycle on each pixel
 start() ->
     {ok, NeoPixel} = neopixel:start(?NEOPIXEL_PIN, ?NUM_PIXELS),
     ok = neopixel:clear(NeoPixel),
@@ -35,6 +36,40 @@ start() ->
     ),
     timer:sleep(infinity).
 
+%% @doc Demo: Fill entire strip with solid colors
+demo_fill() ->
+    {ok, NeoPixel} = neopixel:start(?NEOPIXEL_PIN, ?NUM_PIXELS),
+    ok = neopixel:clear(NeoPixel),
+    %% Cycle through red, green, blue
+    fill_loop(NeoPixel, [{255, 0, 0}, {0, 255, 0}, {0, 0, 255}]).
+
+fill_loop(NeoPixel, []) ->
+    fill_loop(NeoPixel, [{255, 0, 0}, {0, 255, 0}, {0, 0, 255}]);
+fill_loop(NeoPixel, [{R, G, B} | Rest]) ->
+    ok = neopixel:fill_rgb(NeoPixel, R, G, B),
+    ok = neopixel:refresh(NeoPixel),
+    timer:sleep(1000),
+    fill_loop(NeoPixel, Rest).
+
+%% @doc Demo: Set multiple pixels with a pattern using set_pixels_rgb
+demo_pattern() ->
+    {ok, NeoPixel} = neopixel:start(?NEOPIXEL_PIN, ?NUM_PIXELS),
+    ok = neopixel:clear(NeoPixel),
+    %% Create a rainbow pattern
+    Pattern = [{255, 0, 0}, {255, 127, 0}, {0, 255, 0}, {0, 0, 255}],
+    pattern_loop(NeoPixel, Pattern, 0).
+
+pattern_loop(NeoPixel, Pattern, Offset) ->
+    %% Rotate the pattern by Offset positions
+    RotatedPattern = rotate_list(Pattern, Offset),
+    ok = neopixel:set_pixels_rgb(NeoPixel, RotatedPattern),
+    ok = neopixel:refresh(NeoPixel),
+    timer:sleep(200),
+    pattern_loop(NeoPixel, Pattern, (Offset + 1) rem length(Pattern)).
+
+rotate_list(List, 0) -> List;
+rotate_list([H | T], N) -> rotate_list(T ++ [H], N - 1).
+
 loop(NeoPixel, I, Hue, SleepMs) ->
     ok = neopixel:set_pixel_hsv(NeoPixel, I, Hue, ?SATURATION, ?VALUE),
     ok = neopixel:refresh(NeoPixel),

idf_component.yml

@@ -0,0 +1,5 @@
+## IDF Component Manager Manifest File
+dependencies:
+  espressif/led_strip: "^3.0.2"
+  idf:
+    version: ">=5.0"