A pair of Drivers for the Bosch BMI270 6-Axis IMU chip

[easytarget]

The existing BMI270 driver in the micropython library is easy to find and use, but has some issues, most notably a 2300 ms init time

While working on my Tab5 I wanted a higher functionality driver for the BMI270; this resulted in Two drivers:

https://codeberg.org/easytarget/bmi270-micropython

See the README in the repo, plus there are a couple of demo_ programs to explore the basic (IMU) data and advanced feature detection/operation of the drivers

A basic driver:

bmi270_fast.py

• A direct drop-in replacement for the micropython-lib driver
  * 1/5th the size, and at 95 ms it has 25x faster init()
• Provides Acceleration and Gyroscope readings in all three axes.
• Extended with:
  * (Re)Setting of Sensor Ranges and Output Data Rates (ODR) after init()
  * Entering 'adavnced powersave mode' and enabling / disabling specific sensors and filter power modes.
  * Device internal temperature() method has been added.

A 'feature' driver

bmi270_legacy.py

Provides all the features of the fast driver above, but has been extended to use the 'legacy' config provided by Bosch and provides additional 'sensors' and 'features' optimised for Tablet and Phone devices (eg the Tab5 I am working with).

Working:

Orientation, face up/down, activity tracking, step counting
No-motion, any-motion, significant-motion, flat, hi and low G detection
Tap detection, step detection and count watermarking
Detailed options for orientation, motion and detectors
Interrupt pin mode setting and masking

Not Implemented:

Fast data logging (FIFO mode)
Gyro and acceleration calibration and advanced filtering
Slave (accessory) devices; eg magnetometer
OIS (image stabilisation) slave mode
NVM settings memory
A few other advanced/obscure things this chip can do