ADXRS290 no-OS Driver

Supported Devices

• ADXRS290

Overview

The ADXRS290 is a high-performance MEMS pitch and roll rate gyroscope designed for use in stabilization applications. It features an ultralow noise performance of 0.004°/s/√Hz and delivers an output full-scale range of ±100°/s with a sensitivity of 200 LSB/°/s, ensuring precise angular rate measurements. The gyroscope incorporates programmable high-pass and low-pass filters and boasts high vibration rejection over a wide frequency range for robust operation in dynamic environments. Additionally, it offers a power-saving standby mode with an 80 µA current consumption, fast startup time (<100 ms), and a low delay (<0.5 ms for a 30 Hz input). Packaged in a compact 4.5 mm × 5.8 mm × 1.2 mm cavity laminate format, the ADXRS290 is ideally suited for integration into advanced motion sensing and stabilization systems.

Applications

• Optical image stabilization

• Platform stabilization

• Wearable products

Operation Modes

Mode Name	Description	Configuration Bits		Typical Use
Standby	Low-power state, prepared for configuration and conserving energy.	ADXRS290_TSM | Minimal power consumption or temporary pause in measurements.
Measurement	Actively acquires sensor data for angular velocity and temperature.	ADXRS290_MEASUREMENT | Active data acquisition or real-time monitoring.

Device Configuration

The ADXRS290 driver exposes a comprehensive API through its header file, grouping its public functions into several categories based on their roles in device configuration. Each of these functions is designed to facilitate a specific aspect of sensor management from initialization to data retrieval.

Initialization and Cleanup

The initialization category includes the functions adxrs290_init() and adxrs290_remove(). The adxrs290_init() function is responsible for allocating necessary resources, establishing SPI communication, setting up filter settings, and configuring the sensor’s operational mode, while adxrs290_remove() properly deallocates resources and cleans up the device instance when it is no longer needed.

Register Access

For low-level device interaction, the register access category provides the functions adxrs290_reg_read() and adxrs290_reg_write(). The adxrs290_reg_read() function enables reading from specific registers via the SPI interface, whereas adxrs290_reg_write() allows for writing data to designated registers, forming the foundation for direct hardware communication.

Operational Mode Configuration

Managing the sensor’s overall operating state is achieved through the adxrs290_set_op_mode() function. This function transitions the sensor between standby and measurement modes by manipulating power control register settings, thereby integrating with various system power management schemes.

Filter Configuration

Precise control over signal conditioning is facilitated by the filter configuration functions. The functions adxrs290_get_lpf() and adxrs290_set_lpf() retrieve and configure the low-pass filter parameters, respectively, while adxrs290_get_hpf() and adxrs290_set_hpf() perform analogous operations for the high-pass filter settings. This suite of functions allows for effective noise reduction and signal filtering.

Data Acquisition

Sensor data retrieval is managed by a trio of functions in the data acquisition category. The adxrs290_get_rate_data() function is used to acquire angular velocity (rate) data from a specified channel, adxrs290_get_temp_data() reads temperature measurements, and adxrs290_get_burst_data() supports burst-mode acquisitions for obtaining multiple channel data rapidly.

Active Channel Management

The driver enables customization of sensor operations through active channel management. The adxrs290_set_active_channels() function configures which data channels are enabled by setting the appropriate channel mask, ensuring that only the desired sensor streams are active.

Data Readiness

To support reliable data processing, the data readiness category includes the adxrs290_get_data_ready() function. This function checks the status of the sensor’s data ready signal, providing a synchronization mechanism that confirms when new measurement data is available for retrieval.

Driver Initialization Example

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include "adxrs290.h"
#include "no_os_spi.h"
#include "no_os_gpio.h"
#include "no_os_error.h"

static struct adxrs290_dev *gyro_dev;

int main(void)
{
    int32_t ret;
    struct adxrs290_init_param init_param = {
        .spi_init = {
                .device_id      = 0,
                .max_speed_hz   = 4000000,
                .chip_select    = 0,
                .mode           = NO_OS_SPI_MODE_3,
                .platform_ops   = &aducm_spi_ops,
                .extra          = &adxrs290_spi_extra_ip
        },
        .gpio_sync = {
                .port           = 0x10,
                .number         = 0,
                .pull           = NO_OS_PULL_NONE,
                .platform_ops   = &aducm_gpio_ops,
                .extra          = NULL
        },
        .mode       = ADXRS290_MODE_MEASUREMENT,
        .lpf        = ADXRS290_LPF_480HZ,
        .hpf        = ADXRS290_HPF_ALL_PASS
    };

    /* Initialize the ADXRS290 device */
    ret = adxrs290_init(&gyro_dev, &init_param);
    if (ret != 0) {
        printf("ADXRS290 initialization failed: %d\n", ret);
        return ret;
    }

    printf("ADXRS290 initialization successful\n");

    /* Perform cleanup */
    ret = adxrs290_remove(gyro_dev);
    if (ret != 0) {
        printf("ADXRS290 removal failed: %d\n", ret);
        return ret;
    }

    return 0;
}