esp32c3-buddy

MnemOS ESP32-C3 WiFi Buddy

This directory contains the MnemOS firmware for the ESP32-C3 WiFi Buddy.

Target Boards

The currently targeted ESP32-C3 development boards are the Seeedstudio XIAO ESP32-C3 and its cousin the Adafruit QT Py ESP32-C3. These boards are more or less the same --- they are pinout-compatible and can be flashed over USB-C.

The only substantial difference is that the Adafruit board includes a WS2812 "NeoPixel" RGB LED and a Stemma QT JST connector for I²C devices. Neither of these components are required for the MnemOS WiFi Buddy application, so either board can be used interchangeably.

Getting started with MnemOS on the ESP32-C3

Building

The simplest way to build a MnemOS image for the ESP32-C3 platform to use the just build-c3 Just recipe.

Important

Running Just recipes requires Just to be installed. See https://just.systems for details on using Just.

The two supported ESP32-C3 dev boards are pinout-compatible, but route different pins on the ESP32 to the pins on the dev board. Therefore, this crate contains separate Cargo bin targets for each supported dev board, which configure the I/O pin assignment to match the target devboard before calling into shared code:

• qtpy: MnemOS for the Adafruit QT Py ESP32-C3
• xiao: MnemOS for the Seeedstudio XIAO ESP32-C3

The just build-c3 recipe takes a required argument to select which bin target is built. For example:

$ just build-c3 qtpy   # builds MnemOS for the Adafruit QT Py ESP32-C3
$ just build-c3 xiao   # builds MnemOS for the Seeedstudio XIAO ESP32-C3

Alternatively, Allwinner D1 images can be built manually using Cargo. To build using Cargo, run:

# builds MnemOS for the Adafruit QT Py ESP32-C3
$ cargo build -p mnemos-esp32c3-buddy --bin qtpy --release
# builds MnemOS for the Seeedstudio XIAO ESP32-C3
$ cargo build -p mnemos-esp32c3-buddy --bin xiao --release

Flashing & Running

ESP32-C3 dev boards can be flashed over USB using cargo-espflash. To flash an ESP32-C3 board with the MnemOS firmware, either run cargo espflash flash from within this directory, or run the just flash-c3 Just recipe from anywhere in the MnemOS repository.

Like just build-c3, the target board must be provided:

$ just flash-c3 qtpy   # build and flash the Adafruit QT Py ESP32-C3
$ just flash-c3 xiao   # build and flash the Seeedstudio XIAO ESP32-C3

Important

In order to flash an ESP32-C3 board, the cargo-espflash executable must be installed. The just flash-c3 Just recipe will check if cargo-espflash is present, and prompt to install it if it is not found.

If everything worked successfully, you should see output similar to this:

$ just flash-c3 qtpy
       Found cargo-espflash
cargo build --package mnemos-esp32c3-buddy --bin qtpy --release
    Finished release [optimized] target(s) in 0.04s
cargo espflash --package mnemos-esp32c3-buddy --bin qtpy flash --monitor
[2023-07-28T16:40:37Z INFO ] Serial port: '/dev/ttyACM0'
[2023-07-28T16:40:37Z INFO ] Connecting...
[2023-07-28T16:40:38Z INFO ] Using flash stub
    Finished dev [unoptimized + debuginfo] target(s) in 0.04s
Chip type:         esp32c3 (revision v0.3)
Crystal frequency: 40MHz
Flash size:        4MB
Features:          WiFi, BLE
MAC address:       34:b4:72:ea:44:18
App/part. size:    209,760/4,128,768 bytes, 5.08%
[00:00:00] [========================================]      13/13      0x0
[00:00:00] [========================================]       1/1       0x8000
[00:00:01] [========================================]      67/67      0x10000
[2023-07-28T16:40:41Z INFO ] Flashing has completed!

Alternatively, the board can be flashed manually using cargo-espflash. For example:

$ cargo espflash flash \
    --package mnemos-esp32c3-buddy \
    --bin qtpy \ # or 'xiao'
    --monitor
[2023-07-28T16:40:37Z INFO ] Serial port: '/dev/ttyACM0'
[2023-07-28T16:40:37Z INFO ] Connecting...
[2023-07-28T16:40:38Z INFO ] Using flash stub
    Finished dev [unoptimized + debuginfo] target(s) in 0.04s
Chip type:         esp32c3 (revision v0.3)
Crystal frequency: 40MHz
Flash size:        4MB
Features:          WiFi, BLE
MAC address:       34:b4:72:ea:44:18
App/part. size:    209,760/4,128,768 bytes, 5.08%
[00:00:00] [========================================]      13/13      0x0
[00:00:00] [========================================]       1/1       0x8000
[00:00:01] [========================================]      67/67      0x10000
[2023-07-28T16:40:41Z INFO ] Flashing has completed!

License

MIT + Apache 2.0.