SEN6x Rust Driver

A Rust no-std/std driver for the SEN6x environmental sensor nodes for air quality applications.

Description

This library provides a Rust interface for the SEN6x family of environment sensor nodes (SEN-63C, SEN-65, SEN-66, SEN68). It is designed to be used in no-std environments, making it suitable for use in embedded systems.

Supported features

All described features are supported both in blocking as well as async mode.

• Start/stop measurement
• Read sensor samples (both processed and raw)
• Read device name, ID, and status
• Manage sensor configuration (if applicable for module variant)
  • Temperature offset
  • VOC algorithm tuning
  • NOX algorithm tuning
  • Ambient pressure/altitude
• Reset module
• Forced CO2 recalibration
• Fan Cleaning
• Activate SHT heater

Please see the doc.rs documentation for a feature matrix of the supported features for each module variant.

Unsupported features

• The SEN-60 variant is not yet supported (it has a substantially different command set), but may be added in the future

Rust Features

• async (default): Enables async capabilities of the driver
• defmt: Enables the defmt::Format trait for the defmt logging framework (adds defmt crate as dependency)
• serde: Enables serde support for the driver (adds serde crate as dependency, with default features disabled for no-std compatibility)
• std: Enables std functionality of the driver (unlocks thiserror error macros)
• sen60/sen63/sen65/sen66 (default) /sen68: Enables support for the respective sensor variant. Only one of these features can be enabled at a time. The variant enabled by default is sen66.

Dependencies

This driver depends on the embedded-hal and embedded-hal-async crate for hardware abstraction. If activated by feature defmt, it also implements the defmt::Format trait for the defmt logging framework (and thus depends on defmt) for relevant structs.

For development, it uses the embedded-hal-mock crate for mocking the hardware abstraction layer. For the example, it uses linux-embedded-hal, to be tentatively run on an RPI (not tested yet!).

Usage

To use this driver with the SEN66 variant (default), add the following to your Cargo.toml file:

[dependencies]
sen6x = "0.1.0"

Then, you can use it in your Rust code like this:

// Create peripherals here!

// Create instance of the driver
let mut sen6x = Sen6x::new(&mut timer, i2c);

// Start measurement
match sen6x.start_continuous_measurement() {
    Ok(_) => info!("Measurement started"),
    Err(e) => error!("Error starting measurement: {:?}", e),
}

// Read measurement
match sen6x.get_sample() {
    Ok(values) => {
        info!("Sample: {:?}\n", values);
    }
    Err(e) => error!("Error reading values: {:?}", e),
}

// Stop measurement
match sen6x.stop_measurement() {
    Ok(_) => info!("Measurement stopped"),
    Err(e) => error!("Error stopping measurement: {:?}", e),
}

Testing

The library provides extensive unit tests for all features. To run the tests for all variant (and blocking/async), use the following command:

cargo xtask test-features

This library was tested so far (using the examples) on a Raspberry Pi Pico 2W and an directly connected engineering sample of the SEN-66 module.

Examples

Basic example reading for sensor values are available in the examples-rp2350 directory of the source code repository. Follow the instructions in the README.md in that directory to run the examples on a Raspberry Pi Pico 2/2W.

Links

Module Datasheet: SEN6x Datasheet (developed on version 0.9)

License

This library is licensed under either of

• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0) at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Changelog

v0.1.0 - Initial release

v0.1.1 - Fix keywords issue in Cargo.toml

v0.1.2 - Improve documentation, fix doc.rs build issue, reduce pub visibility

v0.1.3 - Fix unit error for VOC and NOx (should be index points instead of ppb)

v0.1.4 - Serde support (for samples), derive Clone for sample, add std feature to allow for thiserror convenience (all thanks to @sbruton)