Crate sht4x

Crate sht4x 

Source
Expand description

§Sensirion SHT4x Driver for Embedded HAL

A platform agnostic device driver for the Sensirion SHT4x temperature and humidity sensor family. It is based on embedded-hal traits and works in no_std environments.

In theory, it supports all of the sensor family’s devices but has only been tested with the SHT40-AD1B so far.

Build Status crates.io Documentation

§Features

  • Blocking operation
  • Supports all commands specified in the datasheet
  • Explicitly borrows DelayMs for command execution so that it could be shared (among multiple sensors)
  • Could be instantiated with the alternative I2C address for the SHT40-BD1B
  • Uses fixed-point arithmetics for converting raw sensor data into measurements in SI units
    • Based on I16F16 from the fixed crate
    • Allows conversion to floating-point values, if needed
    • Convenience methods for fixed-point conversions to milli degree Celsius or milli percent relative humidity which are commonly used by drivers for other humidity and temperature sensors from Sensirion
  • Optional support for defmt

§Example

ⓘ
use sht4x::Sht4x;
// Device-specific use declarations.

let mut delay = // Device-specific initialization of delay.
let i2c = // Device-specific initialization of I2C peripheral.
let mut sht40 = Sht4x::new(i2c);

let serial = sht40.serial_number(&mut delay);
defmt::info!("serial number: {}", serial);

let measurement = sht40.measure(Precision::Low, &mut delay);
defmt::info!("measurement: {}", &measurement);

if let Ok(measurement) = measurement {
    // Convert temperature measurand into different formats for further
    // processing.
    let int: i32 = measurement.temperature_milli_celsius();
    let fixed: I16F16 = measurement.temperature_celsius();
    let float: f32 = measurement.temperature_celsius().to_num();
}

§embedded-hal-async support

This crate has optional support for the embedded-hal-async crate, which provides async versions of the I2c and DelayNs traits. Async support is an off-by-default optional feature, so that projects which aren’t using embedded-hal-async can avoid the additional dependency.

To use this crate with embedded-hal-async, enable the embedded-hal-async feature flag in your Cargo.toml:

sht4x = { version = "0.2", features = ["embedded-hal-async"] }

Once the embedded-hal-async feature is enabled, construct an instance of the Sht4xAsync struct, providing types implementing the embedded_hal_async::i2c::I2c and embedded_hal_async::delay::DelayNs traits. The Sht4xAsync struct is identical to the Sht4x struct, except that its methods are async fns.

sensor-temp-humidity-sht40 is another driver for this sensor family.

§License

Licensed under either of

at your discretion.

§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.

Structs§

Measurement
A measurement from the sensor in SI units.
SensorData
A measurement from the sensor in raw sensor data.
Sht4x
Driver for STH4x sensors.
Sht4xAsyncembedded-hal-async
Async driver for STH4x sensors.

Enums§

Address
I2C adresses used by STH4x sensors.
Error
Error conditions from accessing SHT4x sensors.
HeatingDuration
Duration of heating when activating the internal heater.
HeatingPower
Heating power to apply when activating the internal heater.
Precision
The precision to request for a measurement.