Esp32s3 - Led doesn't light

[yanshay]

I couldn't get the examples to compile as is, so I used esp-generate (which uses esp-hal 0.23.1) to get a basic application and copied over the entire code from the example (the version that uses esp-hal 0.23.1), added required dependencies and features, everything compiled, but I don't see the led turning on, on two boards.

I'm using what seems to be a standard esp32s3 board, where the docs state the led is ws2812 which I believe is supported by this library, but maybe I'm wrong?

I tried simplifying the example, just writing a single color RED, and it doesn't work either.

Am I missing something?

The code is an exact copy/paste from rev "ad75112", and this is the cargo.toml modifications I made are:

cfg-if = "1.0.0"
esp-hal-smartled = { git = "https://github.com/esp-rs/esp-hal-community", rev = "ad75112"}
smart-leds = "0.4.0"

[features]
default = ["esp32s3"]
esp32s3 = []
esp32 = []
esp32c3 = []
esp32c6 = []
esp32h2 = []
esp32s2 = []

And I'm using it by running:
cargo run --release

[bjoernQ]

Do you happen to use a DevKit-C? There are different versions of that dev-board with the LED on different pins: https://docs.espressif.com/projects/esp-dev-kits/en/latest/esp32s3/esp32-s3-devkitc-1/user_guide.html#getting-started:~:text=Both%20the%20initial%20and%20v1.1%20versions%20of%20ESP32%2DS3%2DDevKitC%2D1%20are%20available%20on%20the%20market.%20The%20main%20difference%20lies%20in%20the%20GPIO%20assignment%20for%20the%20RGB%20LED%3A%20the%20initial%20version%20uses%20GPIO48%2C%20whereas%20v1.1%20uses%20GPIO38.

[yanshay]

This is what I'm using:

[bjoernQ]

Doesn't look like DevKit-C and I don't recognize it. Maybe a photo of the backside tells what this is exactly?

[yanshay]

Here is the back side, it's supposed to be gpio48 driving the led.

[bjoernQ]

I was able to find something very similar on AliExpress - there is a schematic but it's very low-resolution - I can't really read the GPIO number but it might be 48, yes

[yanshay]

I was able to find something very similar on AliExpress - there is a schematic but it's very low-resolution - I can't really read the GPIO number but it might be 48, yes

Yes, it's from AliExpress, and it's supposed to be 48. Just doesn't work. I'm trying all GPIO's now...

Are there different versions of ws2812 that might require some different timing or something?

[yanshay]

Done testing all pins, none work.
Is there any known standard example (not esp-hal) that I could check to see if it 's a board issue or sw issue?

[bjoernQ]

You can use the esp-idf example: https://github.com/espressif/esp-idf/tree/master/examples/get-started/blink

Or maybe you can find an Arduino example if you prefer Arduino

[yanshay]

I found what it is ... I need to solder the bridge there right next to the led.
Is that how it works with these boards in general and I didn't know or is it specific to this one?
Maybe there's logic with that, maybe having the led on that gpio prevents from using it for other things?

[bjoernQ]

Great you found it!

Espressif DevKits don't need you to do anything to enable it

Having it connected might get you in trouble using it for other things or at least would result in annoying blinking doing so

[yanshay]

While on leds, there are three other standard leds on the board that light when flashing/logging/etc.
Are these usually controllable as well in some way on these types of boards? which gpios?

[bjoernQ]

Unfortunately I can't see much on the schematic but one might be just a power indicator and others might be UART TX and RX - so I guess they are not controllable

The only development board I know of which comes with an addressable LED and a regular LED connected to a GPIO is the ESP32-C3 RustBoard

[yanshay]

I think Esp32 boards typically have led on Gpio2.

[jamessizeland]

I'm not sure if it is useful in this case, but a known gotcha here is that some boards (i.e. https://unexpectedmaker.com/shop.html#!/ProS3/p/577095369) require you to pull high the LDO2 PWR ENABLE pin for the RGB LED to work too. This caught me out in the past.