Esp Rust Lighting

Firmware for esp32-c3 microcontroller written in Rust, which shows animations on sk6812 led strip. Compiled animations writen in animation-lang can be uploaded using build in web server.

Description

Main idea of this project is to allow users write their own animations in animation-lang using web-fronend and send them to the microcontroller for demonstrating on sk6812 addressable led strip. For compiling and running animation-lang is used.

• Compiler is running in client browser though webassembly, it converts source code into bytecode (p-code).
• Virtual-machine (p-code machine) is running on microcontroller, which executes received bytecode program.

For details about animation language and examples of programs, please check my animation-lang repository.

Getting Started

Compiling Dependencies

• clang
• pip
• ldproxy
• rust

Flashing Tool

• espflash

Getting sources

1. Clone project repository

   git clone https://github.com/MabaKalox/esp-rust-lighting.git

2. Navigate into it

   cd esp-rust-lighting

Configuring

For operation, Wi-Fi connection is required, and wifi-manager is not implemented yet. So you need to supply SSID and password of your Wi-Fi beforehand. Also you can specify number of leds on your led strip.

1. create cfg.toml file in project directory with following content:

[esp-rust-lighting]
wifi_ssid = "your wifi SSID"
wifi_pass = "your wifi password"
led_quantity = 150

Building

1. Install dependencies listed in Compiling Dependencies
2. Add rust nightly toolchain

   rustup install nightly

3. Add rust-src for nightly toolchain

   rustup component add rust-src --toolchain nightly

4. Build, you should be in project directory

   cargo build --release

Flashing

1. Install espflash

    cargo install espflash

2. Flash, replace /dev/ttyACM0 by path to tty device of connected esp32-c3 over usb.

   espflash --speed 921600 --partition-table partitions.csv /dev/ttyACM0 /target/riscv32imc-esp-espidf/release/esp-rust-lighting
   

Usage

1. Attach data pin of sk6812 led strip to GPIO6 of esp32-c3
2. Power up esp32-c3
3. Wait till both leds on microcontroller turn off

Frontend

Navigate to http://rust_led_strip.local, be sure that your device support mdns. Alternatively you can find ip of microcontroller in your router settings and use ip instead: http://[IP]

• Try to send some program:

  1. Open Programming tab (top left corner).
  2. Try to write some program in left textarea, e.g:

     // Blank everything
     for(n=get_length) {
       set_pixel(n-1, 0, 0, 0);
     };
     loop {
       // set random pixel to random color
       lucky = random(get_length);
       for(n=get_length) {
         if(n == lucky) {
           r = random(255);
           g = random(255);
           b = random(255);
           set_pixel(n-1, r, g, b);
         }
       };
       // Display on led strip
       blit;
       // Black one random pixel
       luckyb = random(get_length);
       for(n=get_length) {
         if(n == luckyb) {
           set_pixel(n-1, 0, 0, 0);
         }
       };
       blit;
     }   
     

  3. Check frame color
     • Green - compiled successfully, disassembly can be found in right window
     • Red - compiling error, detailes can be found in right window
  4. Press Send green button on web page in top right corner
  5. You should see how random pixels turn on and off on led strip

• Try presets (saved programs in your web browser)

  1. Write some program in Programming tab
  2. Click Save button in middle part of screen
  3. Input desired name for preset
  4. Preset should appear under Save button:
  • You can apply it, by clicking on name
  • You can delete it, by clicking X button near name

• Try to change configuration:

  1. Open Configuring tab tab (top right corner)
  2. Here you can change
     • FPS - changes delay between presenting new frames
     • Led Quantity - self-explanatory, worth to note, it is not reboot persistent
     • White brightness - sk6812 has dedicated white led in pixels, and you control their brightness by this setting
  3. Apply by Submit button
  4. Check applied config in window below

REST API

The REST API to the esp-rust-lightning

---

Send compiled program in base64

Request

POST /send_prog_base64

Body

base64 encoded string with compiled program

Example

curl -X POST -d "[base64 encoded compiled program]" http://rust_led_strip.local/send_prog_base64

---

Set configuration

Request

POST /set_conf

Query params

fps - frames per second [0, 255]

white_brightness - brightness of white subpixel in sk6812 [0, 255]

led_quantity - how many leds in led strip to control [0, 2^32-1]

Example

curl -X POST -G -d 'white_brightness=20' -d 'led_quantity=150' -d 'fps=60' http://http://rust_led_strip.local/set_conf

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgments

• esp-rs