drivers/imu/icm40627: Add TDK InvenSense ICM-40627 IMU driver.

Adds I2C driver for the ICM-40627 6-axis MEMS motion tracking device with
3-axis accelerometer and 3-axis gyroscope. Includes configurable
accelerometer range (±2g/4g/8g/16g), temperature sensor support, and basic
usage example.

Author: pi-anl

micropython/drivers/imu/icm40627/icm40627.py

@@ -0,0 +1,164 @@
+# MIT license; Copyright (c) 2025 Planet Innovation
+# ICM-40627 6-axis accelerometer/gyroscope driver for MicroPython.
+
+"""
+ICM-40627 6-axis accelerometer/gyroscope driver for MicroPython.
+
+The ICM-40627 is a 6-axis MEMS Motion Tracking device that combines a
+3-axis accelerometer and 3-axis gyroscope on a single chip.
+"""
+
+# Register addresses (ICM-40627 register map)
+_REG_WHO_AM_I = 0x75
+_REG_PWR_MGMT_1 = 0x4E
+_REG_PWR_MGMT_2 = 0x4F
+_REG_ACCEL_CONFIG0 = 0x50
+_REG_GYRO_CONFIG0 = 0x4F
+_REG_TEMP_CONFIG0 = 0x4D
+_REG_ACCEL_X_H = 0x1F
+_REG_GYRO_X_H = 0x25
+_REG_TEMP_H = 0x1D
+
+# WHO_AM_I expected value
+_WHOAMI_VALUE = 0x4E
+
+# Accelerometer scale factors (sensitivity in LSB/g)
+# ±2g: 16384 LSB/g, ±4g: 8192 LSB/g, ±8g: 4096 LSB/g, ±16g: 2048 LSB/g
+_ACCEL_SCALE_2G = 16384
+_ACCEL_SCALE_4G = 8192
+_ACCEL_SCALE_8G = 4096
+_ACCEL_SCALE_16G = 2048
+
+# Gyroscope scale factors (sensitivity in LSB/°/s)
+# ±2000°/s: 16.4 LSB/°/s
+_GYRO_SCALE = 16.4
+
+# Temperature scale factor: 1/333.87 °C per LSB, offset 21 °C at 0 LSB
+_TEMP_SCALE = 1.0 / 333.87
+_TEMP_OFFSET = 21.0
+
+
+class ICM40627:
+    """
+    Driver for the ICM-40627 6-axis accelerometer/gyroscope.
+
+    Example usage:
+        from machine import I2C
+        from icm40627 import ICM40627
+
+        i2c = I2C(1)
+        imu = ICM40627(i2c, addr=0x6B)
+
+        ax, ay, az = imu.acceleration
+        gx, gy, gz = imu.gyro
+        temp = imu.temperature
+    """
+
+    def __init__(self, i2c, addr=0x6B, accel_range=8):
+        """
+        Initialize the ICM-40627.
+
+        Args:
+            i2c: machine.I2C object for communication
+            addr: I2C address (default 0x6B)
+            accel_range: Accelerometer range in g (2, 4, 8, or 16; default 8)
+        """
+        self.i2c = i2c
+        self.addr = addr
+
+        # Validate device presence
+        self._device_id = self._read_register(_REG_WHO_AM_I)
+        if self._device_id != _WHOAMI_VALUE:
+            raise RuntimeError(
+                f"ICM-40627 not found at address 0x{addr:02X}. "
+                f"Got ID 0x{self._device_id:02X}, expected 0x{_WHOAMI_VALUE:02X}"
+            )
+
+        # Set accelerometer scale
+        if accel_range == 2:
+            self._accel_scale = _ACCEL_SCALE_2G
+            self._accel_config = 0x00  # ±2g
+        elif accel_range == 4:
+            self._accel_scale = _ACCEL_SCALE_4G
+            self._accel_config = 0x01  # ±4g
+        elif accel_range == 8:
+            self._accel_scale = _ACCEL_SCALE_8G
+            self._accel_config = 0x02  # ±8g
+        elif accel_range == 16:
+            self._accel_scale = _ACCEL_SCALE_16G
+            self._accel_config = 0x03  # ±16g
+        else:
+            raise ValueError("accel_range must be 2, 4, 8, or 16")
+
+        # Initialize the device
+        self._initialize()
+
+    def _initialize(self):
+        """Initialize ICM-40627 with default configuration."""
+        # Exit sleep mode
+        self._write_register(_REG_PWR_MGMT_1, 0x00)
+
+        # Set accelerometer configuration
+        self._write_register(_REG_ACCEL_CONFIG0, self._accel_config << 5)
+
+        # Set gyroscope configuration to ±2000°/s
+        self._write_register(_REG_GYRO_CONFIG0, 0x00 << 5)
+
+    def _read_register(self, reg):
+        """Read a single register value."""
+        data = self.i2c.readfrom_mem(self.addr, reg, 1)
+        return data[0]
+
+    def _read_registers(self, reg, count):
+        """Read multiple consecutive registers."""
+        return self.i2c.readfrom_mem(self.addr, reg, count)
+
+    def _write_register(self, reg, value):
+        """Write a single register value."""
+        self.i2c.writeto_mem(self.addr, reg, bytes([value]))
+
+    def _read_int16(self, reg):
+        """Read a 16-bit signed integer from two consecutive registers."""
+        data = self._read_registers(reg, 2)
+        value = (data[0] << 8) | data[1]
+        # Convert to signed
+        if value & 0x8000:
+            value -= 0x10000
+        return value
+
+    @property
+    def acceleration(self):
+        """
+        Read accelerometer data.
+
+        Returns:
+            Tuple of (x, y, z) acceleration in g units
+        """
+        x = self._read_int16(_REG_ACCEL_X_H) / self._accel_scale
+        y = self._read_int16(_REG_ACCEL_X_H + 2) / self._accel_scale
+        z = self._read_int16(_REG_ACCEL_X_H + 4) / self._accel_scale
+        return (x, y, z)
+
+    @property
+    def gyro(self):
+        """
+        Read gyroscope data.
+
+        Returns:
+            Tuple of (x, y, z) angular velocity in degrees per second
+        """
+        x = self._read_int16(_REG_GYRO_X_H) / _GYRO_SCALE
+        y = self._read_int16(_REG_GYRO_X_H + 2) / _GYRO_SCALE
+        z = self._read_int16(_REG_GYRO_X_H + 4) / _GYRO_SCALE
+        return (x, y, z)
+
+    @property
+    def temperature(self):
+        """
+        Read temperature sensor data.
+
+        Returns:
+            Temperature in degrees Celsius
+        """
+        raw = self._read_int16(_REG_TEMP_H)
+        return (raw * _TEMP_SCALE) + _TEMP_OFFSET

micropython/drivers/imu/icm40627/icm40627_basic.py

@@ -0,0 +1,18 @@
+# MIT license; Copyright (c) 2025 Planet Innovation
+# ICM-40627 basic example
+
+import time
+from icm40627 import ICM40627
+from machine import I2C
+
+# Initialize I2C and IMU
+i2c = I2C(1)
+imu = ICM40627(i2c, addr=0x6B, accel_range=8)
+
+# Read and display sensor data
+while True:
+    print("Accelerometer: x:{:>8.3f} y:{:>8.3f} z:{:>8.3f}".format(*imu.acceleration))
+    print("Gyroscope:     x:{:>8.3f} y:{:>8.3f} z:{:>8.3f}".format(*imu.gyro))
+    print("Temperature:   {:>8.2f}°C".format(imu.temperature))
+    print("")
+    time.sleep_ms(100)

micropython/drivers/imu/icm40627/manifest.py

@@ -0,0 +1,6 @@
+metadata(
+    description="TDK InvenSense ICM-40627 6-axis IMU driver (I2C).",
+    version="1.0.0",
+)
+
+module("icm40627.py", opt=3)