mh-zx-driver

MH-Z* family CO2 sensor driver built on top of embedded-hal primitives. This is a no_std crate suitable for use on bare-metal. The API is non-blocking (in a way compatible with the nb crate).

Supported devices

The code has been tested with MH-Z19B sensor, other sensors in MH-Z* family support the same UART protocol.

Datasheets

• MH-Z19B
• MH-Z19
• MH-Z14

More resources

• https://revspace.nl/MHZ19
• https://revspace.nl/MH-Z19B
• https://habr.com/en/post/401363/

lib.rs:

MH-Z* CO2 sensor driver

MH-Z* family CO2 sensor driver built on top of embedded-hal primitives. This is a no_std crate suitable for use on bare-metal.

Usage

The Sensor struct exposes methods to send commands (write_packet_op) to the sensor and to read the response(read_packet_op).

Example

use mh_zx_driver::{commands, Sensor, Measurement};
use nb::block;
use core::convert::TryInto;

let mut sensor = Sensor::new(uart);
// Send command to the sensor.
{
  let mut op = sensor.write_packet_op(commands::READ_CO2);
  block!(op()).unwrap();
};
// Read the response.
let mut packet = Default::default();
{
  let mut op = sensor.read_packet_op(&mut packet);
  block!(op()).unwrap();
}
let meas: Measurement = packet.try_into().unwrap();
println!("CO2 concentration: {}", meas.co2);

Future support

The experimental support for async/await can be activated by enabling the async feature in Cargo.toml. It adds async methods to the Sensor struct. Constructs the Sensor interface from 2 'halves' of UART.