MicroPython BMI160 Library¶

`bmi160`¶

MicroPython Driver for the Bosch BMI160 Acc/Gyro Sensor

Author(s): Jose D. Montoya

class micropython_bmi160.bmi160.BMI160(i2c, address: int = 0x69)[source]¶

Driver for the BMI160 Sensor connected over I2C.

Parameters:¶

i2c : I2C¶: The I2C bus the BMI160 is connected to.
address : int¶: The I2C device address. Defaults to 0x69

Raises:¶

RuntimeError – if the sensor is not found

Quickstart: Importing and using the device

Here is an example of using the BMI160 class. First you will need to import the libraries to use the sensor

from machine import Pin, I2C
from micropython_bmi160 import bmi160

Once this is done you can define your machine.I2C object and define your sensor object

i2c = I2C(1, sda=Pin(2), scl=Pin(3))
bmi160 = bmi160.BMI160(i2c)

Now you have access to the attributes

accx, accy, accz = bmi.acceleration
gyrox, gyroy, gyroz = bmi.gyro

acc_power_mode(value: int) → None[source]¶

Mode	Value
`bmi160.ACC_POWER_SUSPEND`	`0x10`
`bmi160.ACC_POWER_NORMAL`	`0x11`
`bmi160.POWER_LOWPOWER`	`0x12`

property acceleration : tuple[int, int, int]¶: Sensor Acceleration

property acceleration_bandwidth_parameter : str¶

Determines filter configuration (acc_us=0) and averaging for undersampling mode (acc_us=1).

Mode	Value
`bmi160.FILTER`	`0`
`bmi160.AVERAGING`	`1`

property acceleration_output_data_rate : str¶

Define the output data rate in Hz is given by \(100/2^(8-accodr)\) The output data rate is independent of the power mode setting for the sensor

Configurations without a bandwidth number are illegal settings and will result in an error code in the Register (0x02) ERR_REG.

At startup this is setup at 100 Hz

Mode	Value
`bmi160.BANDWIDTH_25_32`	`0b0001` 25/32 Hz
`bmi160.BANDWIDTH_25_16`	`0b0010` 25/16 Hz
`bmi160.BANDWIDTH_25_8`	`0b0011` 25/8 Hz
`bmi160.BANDWIDTH_25_4`	`0b0100` 25/4 Hz
`bmi160.BANDWIDTH_25_2`	`0b0101` 25/2 Hz
`bmi160.BANDWIDTH_25`	`0b0110` 25 Hz
`bmi160.BANDWIDTH_50`	`0b0111` 50 Hz
`bmi160.BANDWIDTH_100`	`0b1000` 100 Hz
`bmi160.BANDWIDTH_200`	`0b1001` 200 Hz
`bmi160.BANDWIDTH_400`	`0b1010` 400 Hz
`bmi160.BANDWIDTH_800`	`0b1011` 800 Hz
`bmi160.BANDWIDTH_1600`	`0b1100` 1600 Hz

property acceleration_range : str¶

The register allows the selection of the accelerometer g-range. Changing the range of the accelerometer does not clear the data ready bit in the Register (0x1B) STATUS. It is recommended to read the Register (0x04-0x17) DATA after the range change to remove a stall data ready bit from before the range change.

Mode	Value
`bmi160.ACCEL_RANGE_2G`	`0b0011`
`bmi160.ACCEL_RANGE_4G`	`0b0101`
`bmi160.ACCEL_RANGE_8G`	`0b1000`
`bmi160.ACCEL_RANGE_16G`	`0b1100`

property acceleration_undersample : str¶

The undersampling parameter is typically used in low power mode. When acc_us is set to ‘0’ and the accelerometer is in low-power mode, it will change to normal mode. If the acc_us is set to ‘0’ and a command to enter low-power mode is sent to the Register (0x7E) CMD, this command is ignored.

Mode	Value
`bmi160.NO_UNDERSAMPLE`	`0`
`bmi160.UNDERSAMPLE`	`1`

error_code() → None[source]¶

The register is meant for debug purposes, not for regular verification if an operation completed successfully.

Fatal Error: Error during bootup. Broken hardware(e.g.NVM error, see ASIC spec for details).This flag will not be cleared after reading the register.The only way to clear the flag is a POR.

Error flags (bits 7:4) store error event until they are reset by reading the register.

property gyro : tuple[int, int, int]¶: Gyro values

property gyro_bandwidth_parameter : str¶

The gyroscope bandwidth coefficient defines the 3 dB cutoff frequency: of the low pass filter for the sensor data.

When the filter mode is set to normal (gyr_bwp=0b10), the gyroscope data is sampled at equidistant points in the time, defined by the gyroscope output data rate parameter (gyr_odr). The output data rate can be configured in one of eight different valid ODR configurations going from 25Hz up to 3200Hz.

When the filter mode is set to OSR2 (gyr_bwp=0b01), both stages of the digital filter are used and the data is oversampled with an oversampling rate of 2. That means that for a certain filter configuration, the ODR has to be 2 times higher than in the normal filter mode. Conversely, for a certain filter configuration, the filter bandwidth will be the approximately half of the bandwidth achieved for the same ODR in the normal filter mode. For example, for ODR=50Hz we will have a 3dB cutoff frequency of 10.12Hz.

When the filter mode is set to OSR4 (gyr_bwp=0b000), both stages of the digital filter are used and the data is oversampled with an oversampling rate of 4. That means that for a certain filter configuration, the ODR has to be 4 times higher than in the normal filter mode. Conversely, for a certain filter configuration, the filter bandwidth will be approximately 4 times smaller than the bandwidth achieved for the same ODR in the normal filter mode. For example, for ODR=50Hz we will have a 3dB cutoff frequency of 5.06Hz.

Mode	Value
`bmi160.GYRO_NORMAL`	`0b10`
`bmi160.GYRO_OSR2`	`0b01`
`bmi160.GYRO_OSR4`	`0b00`

property gyro_output_data_rate : str¶

Define the output data rate in Hz is given by \(100/2^(8-gyroodr)\) The output data rate is independent of the power mode setting for the sensor

Configurations without a bandwidth number are illegal settings and will result in an error code in the Register (0x02) ERR_REG.

Warning

Lower ODR values than 25Hz are not allowed. If they are used they result in an error code in Register (0x02) ERR_REG.

At startup this is setup at 100 Hz

Mode	Value
`bmi160.BANDWIDTH_25`	`0b0110` 25 Hz
`bmi160.BANDWIDTH_50`	`0b0111` 50 Hz
`bmi160.BANDWIDTH_100`	`0b1000` 100 Hz
`bmi160.BANDWIDTH_200`	`0b1001` 200 Hz
`bmi160.BANDWIDTH_400`	`0b1010` 400 Hz
`bmi160.BANDWIDTH_800`	`0b1011` 800 Hz
`bmi160.BANDWIDTH_1600`	`0b1100` 1600 Hz
`bmi160.BANDWIDTH_3200`	`0b1101` 3200 Hz

property gyro_power_mode : str¶

Mode	Value
`bmi160.GYRO_POWER_SUSPEND`	`0x14`
`bmi160.GYRO_POWER_NORMAL`	`0x15`
`bmi160.GYRO_POWER_FASTSTARTUP`	`0x17`

property gyro_range : str¶

The register allows the selection of the gyro g-range. Changing the range of the accelerometer does not clear the data ready bit in the Register (0x1B) STATUS. It is recommended to read the Register (0x04-0x17) DATA after the range change to remove a stall data ready bit from before the range change.

Mode	Value
`bmi160.GYRO_RANGE_2000`	`0b000`
`bmi160.GYRO_RANGE_1000`	`0b001`
`bmi160.GYRO_RANGE_500`	`0b010`
`bmi160.GYRO_RANGE_250`	`0b011`
`bmi160.GYRO_RANGE_125`	`0b100`

power_mode_status() → None[source]¶: Returns Power mode status

soft_reset() → None[source]¶

Performs a Soft Reset

Returns:¶: None

property temperature : int¶

The temperature is disabled when all sensors are in suspend mode. The output word of the 16-bit temperature sensor is valid if the gyroscope is in normal mode, i.e. gyr_pmu_status=0b01. The resolution is typically \(1/2^9\) K/LSB.

If the gyroscope is in normal mode (see Register (0x03) PMU_STATUS), the temperature is updated every 10 ms (+-12%). If the gyroscope is in suspend mode or fast-power up mode, the temperature is updated every 1.28 s aligned :return: int

MicroPython BMI160 Library¶

bmi160¶

`bmi160`¶