iis2mdc-rs

This crate provides a platform-agnostic driver for the ST IIS2MDC digital magnetic sensor, supporting both I2C and SPI communication interfaces.

Sensor Overview

The IIS2MDC is a high-accuracy, ultra-low-power 3-axis digital magnetic sensor. The IIS2MDC has a magnetic field dynamic range up to ±50 gauss. The IIS2MDC includes an I2C serial bus interface that supports standard, fast mode, fast mode plus, and high-speed (100 kHz, 400 kHz, 1 MHz, and 3.4 MHz) and an SPI serial standard interface. The device can be configured to generate an interrupt signal for magnetic field detection. The IIS2MDC is available in a plastic land grid array package (LGA) and is guaranteed to operate over an extended temperature range from -40 °C to +85 °C.

For more info, please visit the device page at ST IIS2MDC.

Installation

Add the driver to your Cargo.toml dependencies:

[dependencies]
iis2mdc-rs = "0.1.0"

Or, add it directly from the terminal:

cargo add iis2mdc-rs

Usage

Include the crate and its prelude

use iis2mdc_rs as iis2mdc;
use iis2mdc::*;
use iis2mdc::prelude::*;

Create an instance

Create an instance of the driver with the new_<bus> associated function, by passing an I2C (embedded_hal::i2c::I2c) instance and I2C address, or an SPI (embedded_hal::spi::SpiDevice) instance, along with a timing peripheral.

An example with I2C:

let mut sensor = Iis2mdc::new_i2c(i2c, I2CAddress::I2cAdd, delay);

Check "Who Am I" Register

This step ensures correct communication with the sensor. It returns a unique ID to verify the sensor's identity.

let whoami = sensor.device_id_get().unwrap();
if whoami != ID {
    panic!("Invalid sensor ID");
}

Configure

See details in specific examples; the following are common api calls:

// Restore default configuration
sensor.reset_set(PROPERTY_ENABLED).unwrap();
loop {
    if sensor.reset_get().unwrap() == 0 {
        break;
    }
}

// Enable block data update
sensor.block_data_update_set(PROPERTY_ENABLED).unwrap();
// Set output data rate
sensor.data_rate_set(Odr::_10hz).unwrap();
// Set / Reset sensor mode
sensor
    .set_rst_mode_set(SetRst::SensOffCancEveryOdr)
    .unwrap();

// Enable temperature compensation
sensor.offset_temp_comp_set(PROPERTY_ENABLED).unwrap();
// Set device in continuous mode
sensor.operating_mode_set(Md::ContinuousMode).unwrap();
// Power up and wait for 20ms for stable output
sensor.tim.delay_ms(20);

License

Distributed under the BSD-3 Clause license.

More Information: http://www.st.com.

Copyright (C) 2025 STMicroelectronics