Monitor air quality, starting with C02. This project currently uses the ESP32-C3 MCU and is implemented in Rust (no_std). It periodically reads the sensor data (CO2, temperature, humidity) and displays it on an e-ink display. See Display Themes for more info on the display themes.

To build:

cd esp32c3_nostd
cargo build --release

To flash:

cd esp32c3_nostd
cargo run --release

• Sensirion SCD41
• ESP32-C3-DevKitC-02
• 2.9inch E-Paper E-Ink Display Module (B)

I2C and SPI2 can be used on any GPIO pins.

Connections:

• I2C SCL (yellow) -> GPIO0
• I2C SDA (green) -> GPIO1
• GND (black) -> GND
• VDD (red) -> 3.3 V

https://www.waveshare.com/product/displays/e-paper/epaper-2/2.9inch-e-paper-module-b.htm

• VCC: 3.3V/5V
• GND: Ground
• DIN: SPI MOSI pin
• CLK: SPI SCK pin
• CS: SPI chip selection, low active
• DC: Data / Command selection (high for data, low for command)
• RST: External reset, low active
• BUSY: Busy status output, low active

Connections:

• VCC -> 3.3 V
• GND -> GND
• DIN (MOSI) -> GPIO4
• CLK (SCK) -> GPIO5
• CS -> GPIO6
• DC (MISO) -> GPIO7
• RST -> GPIO18
• BUSY -> GPIO19

• https://github.com/Sensirion/arduino-ble-gadget/blob/master/documents/SCD4x_BLE_Gadget_Tutorial.md
• https://www.espressif.com/sites/default/files/documentation/esp32-c3_datasheet_en.pdf
• https://docs.rust-embedded.org/discovery/microbit/08-i2c/index.html
• https://docs.rs/esp32c3-hal/latest/esp32c3_hal/i2c/index.html
• https://www.allaboutcircuits.com/technical-articles/spi-serial-peripheral-interface
• https://github.com/waveshareteam/Pico_ePaper_Code
• https://projects.raspberrypi.org/en/projects/button-switch-scratch-pi/1
• https://microcontrollerslab.com/push-button-esp32-gpio-digital-input/

• hauju for releasing https://github.com/hauju/scd4x-rs
• caemor for https://github.com/caemor/epd-waveshare
• Everyone else involved in open source embedded Rust