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Fetch raw data from MPU9250 sensors

Download, install and enable iiod server on NanoPi,

sudo apt install iiod
sudo systemctl enable iiod

Now any device on the network can interact with the inertial motion unit, install python3-libiio then use the following code to get raw data,

import iio

class IMUConnection:
    channels = ["accel_x", "accel_y", "accel_z",
                "anglvel_x", "anglvel_y", "anglvel_z"]

    def __init__(self, ip: str, device_name: str):
        self.ip = ip
        self.device_name = device_name

    def __enter__(self):
        """
        Connect to NanoPi and enable inertial motion unit device
        """
        context = iio.NetworkContext(self.ip)
        self.device = context.find_device(self.device_name)
        for c in self.channels:
            self.device.find_channel(c).enabled = True
        self.buffer = iio.Buffer(self.device, 1)
        return self

    def __exit__(self, *exc_info):
        """
        Disable channels on exit
        """
        for c in self.channels:
            self.device.find_channel(c).enabled = True

    def get_raw_acc_gyr(self):
        """
        Return raw output from accelerometer and gyrometer
        """
        self.buffer.refill()
        h = self.buffer.read()
        acc_raw = [int.from_bytes(h[i:i+2], byteorder='big',
                                  signed=True) for i in range(0, 6, 2)]
        gyr_raw = [int.from_bytes(h[i:i+2], byteorder='big',
                                  signed=True) for i in range(6, 12, 2)]
        return acc_raw, gyr_raw


with IMUConnection("10.42.0.1", "mpu6050") as imu:
    for i in range(100):
        acc_raw, gyr_raw = imu.get_raw_acc_gyr()
        print("Acc:", acc_raw, "Gyro:", gyr_raw)