The project works GREAT. However, When I add Wifi to my project - I often get pixels set incorrectly/randomly. The problem predictably gets much worse if I start pinging the ESP32 like crazy (more network traffic).

I have seen similar cases in other project where interrupts are enabled and it throws the timing of of the pixel updates. I am assuming this is is a problem where network interrupts (or threads?) are being prioritized over the RMT interrupts, making the additional "half" buffer fills happen too late?

I'm struggling to fix this - don't know if anyone else has any more insight for me,

It seem that ESP-IDF v5.x has deprecated the RMT framework used in v4.x

Please see: https://docs.espressif.com/projects/esp-idf/en/v5.0.2/esp32/migration-guides/release-5.x/peripherals.html#rmt-driver

Any plans to support the new framework v5.x?

Your NeoPixel method is much cleaner than the ESP-IDF supplied example!

With this module ESP32-NeoPixel-WS2812-RMT not work.
http://github.com/wuxx/nanoesp32-s2/blob/master/doc/nanoESP32-S2.jpg
When add attribute flag = 0 then it works!

void ws2812_control_init(void)
{
  rmt_config_t config;// = RMT_DEFAULT_CONFIG_TX(LED_RMT_TX_GPIO, LED_RMT_TX_CHANNEL);
  config.rmt_mode = RMT_MODE_TX;
  config.channel = LED_RMT_TX_CHANNEL;
  config.gpio_num = LED_RMT_TX_GPIO;
  config.mem_block_num = 3;
  config.flags = 0;             <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<fix
  config.tx_config.loop_en = false;
  config.tx_config.carrier_en = false;
  config.tx_config.idle_output_en = true;
  config.tx_config.idle_level = RMT_IDLE_LEVEL_LOW;
  config.clk_div = 2;

  ESP_ERROR_CHECK(rmt_config(&config));
  ESP_ERROR_CHECK(rmt_driver_install(config.channel, 0, 0));
}

Hello Jordan,

I grabbed the code and put it in my project. It works fine (on 1 LED).
I will be hacking it up a bit, I will change the hardcoded pin-numbers into runtime parameters.
Your solution using the RMT was the most elegant one I found for controlling the WS2812 devices, no assembly or dependencies. Very good.

The best wishes from The Netherlands,
Edwin

After some time I found a serious bug in the code : reference to uninitialized data. Not so good!
Here is the fix (ws2812_control.c about line 24)

void ws2812_control_init(void)
{
    rmt_config_t config = {
        .rmt_mode = RMT_MODE_TX,
        .channel = LED_RMT_TX_CHANNEL,
        .gpio_num = LED_RMT_TX_GPIO,
        .mem_block_num = 3,
        .tx_config.loop_en = false,
        .tx_config.carrier_en = false,
        .tx_config.idle_output_en = true,
        .tx_config.idle_level = RMT_IDLE_LEVEL_LOW,
        .clk_div = 2,
    };

is created on the stack but only some values of the memory are filled in.
This leads to the .flag part not being 0x00 when it should be, (it thinks RMT_CHANNEL_FLAGS_ALWAYS_ON) which leads to using the wrong clock source (1 MHz ref instead of RMT_BASECLK_APB)

The solution is simple, RAII : Resource Acquisition Is Initialization.

Just do it like this :

rmt_config_t config = {0,};

or even better:

rmt_config_t config = {
        .rmt_mode = RMT_MODE_TX,
        .channel = LED_RMT_TX_CHANNEL,
        .gpio_num = LED_RMT_TX_GPIO,
        .mem_block_num = 3,
        .tx_config.loop_en = false,
        .tx_config.carrier_en = false,
        .tx_config.idle_output_en = true,
        .tx_config.idle_level = RMT_IDLE_LEVEL_LOW,
        .clk_div = 2,
    };

Hi, I'm going to try to incorporate your lib into my project, but I'm going to have to arrive at the RMT bit timings by trial and error since I don't have access to a logic analyzer and I don't use WS2812 (I use WS2812b or WS2811). Below are some bit timing values that I've collected from the various WS28xx datasheets.

That said, I don't understand your "low" timing values. All bits should have a constant time, meaning the microseconds of a 0 bit should be the same as a 1 bit. Unfortunately, the WS2812 datasheet contradicts itself by saying all bit times are 1.25us, then it gives TH/TL values that don't add up to 1.25 (as the other datasheets do). The SparkFun datasheet you reference does give equal 0/1 bit times, but they are 1.71us each. The lights must be able to accept a lot of variance, but it's probably best to get as close as possible to the datasheet values for stability and transmission rate.

I assume that your CPU and peripheral clock speeds are the default values?

Thanks, dave

/* LED TIMINGS, per their datasheets:
*

• WS2811: (1.25 or 2.5us bit time, 800 or 400Kbps)
• T0H: 0.25 or 0.5us <-- 0 bit
• T0L: 1.0 or 2.0us
• T1H: 0.6 or 1.2us <-- 1 bit
• T1L: 0.65 or 1.3us
• RES: 50us
• WS2812: (1.25us bit time, 800Kbps)
• T0H: 0.35us <-- 0 bit
• T0L: 0.8us
• T1H: 0.7us <-- 1 bit
• T1L: 0.6us
• RES: 50us
• WS2812b: (1.25us bit time, 800Kbps)
• T0H: 0.4us <-- 0 bit
• T0L: 0.85us
• T1H: 0.8us <-- 1 bit
• T1L: 0.45us
• RES: 50us
  */

I've tried your code on an ESP32-S3 yesteday and couldn't get the LED to work (no sign of life at all).
Here is a datasheet, if that helps: https://datasheet.lcsc.com/lcsc/2211021800_XINGLIGHT-XL-3528RGBW-WS2812B_C2890364.pdf

Hello there,
Just downloaded the code, and I'm getting the above compile error on line 27 of ws2812_control.c ("config.gpio_num = LED_RMT_TX_GPIO;"). Arduino IDE v1.8.9. Just thought I'd mention it here.

Predefined LED's?

Got this idea when I was messing about with LED timings in Issue #13 and found it somewhat useful to have predefined LED timings instead of having to write them down somewhere else. This is a small detail since most WS28xx LEDs have similar timing specs but it might still be useful to easily ensure that all LEDs operate within the proper specifications.

I forked your repo and made the necessary changes to implement such a thing.
Also added a range limitation on the RMT channel configuration, the help text states "Defines that RMT Channel that will be used to modulate the signal. Valid values are defined by enum rmt_channel_t (0-7)" but the input data field is not sanity checked. Limited the input to channel 0-7.

Tested the code on an ESP32 and WS2812B and it works fine.
Below is a demo video of the esp-idf configuration tool with the predefined LEDs.

The README.md is also adjusted, it was never updated when migrating the code to the esp-idf configurator.

NOTE: The timings should be double checked, I don't own all of the LEDs so I'm unable to test them.

Good day,

I am attempting to make this work with another digital LED (Specifically, the IN-PI554FCH).
This LED has the following timing specifications T0H = 0.3uS, T1H = 0.6uS, T0L = 0.9uS, T1L = 0.6uS.
I would just like to know what the clock speed should be set to. I do now have a very good scope so it is difficult for me to get the timing of the signals.

Thank you in advance.