BMA456 Wearable feature documentation

[GreenBean23]

Hi,

could BOSCH Sensortec please update the documentation of the wearable feature set?

The latest downloadable Application Note - Wearable Feature Set rev. 1.2 as of January 2021 (BST-MAS-AN032-02) does not match the sensor's behaviour when configured using the configuration file in bma456w.c as provided by the driver suite V2.24.2 as of 01.07.2022.

Especially, the feature offsets from from 0x3C on differ as follows:

Documented in Application Note:

• 0x3C: single_tap setting
• 0x3E: double_tap settings
• 0x40: wrist_wear_wakeup settings
• 0x42 config_id
• 0x44 axes_remapping

While treatment in the driver code is:

• 0x3C wrist_wakeup enable
• 0x3E wrist_wakeup parameter: minimum focus angle
• 0x40 wrist_wakeup parameter: minimum non-focus angle
• 0x42 wrist_wakeup parameter: landscape left/right angle
• 0x44 wrist_wakeup parameter: portrait up/down angle
• 0x46 wrist_wakeup parameter: durations moved/quiet
• 0x48 config_id
• 0x4A axes_remapping

BTW: Where is the single/double tap setting gone in the driver implementation ....?

And more generally: Is there a documentation on how to write own configuration files?

[BSTRobin]

Hi GreenBean23，

You'd better refer to the BMA456 sensor API and sample program on github. The document may not be updated to the latest, but the firmware, sensor API and sample program on github are the latest. The sample program has implemented the configuration and interface to access the feature and can be used directly.

You can refer to readme on github and select different firmware and sensor APIs and examples according to your application.
https://github.com/boschsensortec/BMA456-Sensor-API/blob/master/README.md

BMA456 Sensor API

This package contains SensorAPIs for BMA456 Sensor

Sensor Overview

The BMA456 is an ultra-small, triaxial, low-g acceleration sensor with digital interfaces, aiming for low-power consumer electronics applications. Featuring 16 bit digital resolution and embedded intelligence, the device is optimized to fulfill low power accelerometer requirements.
Applications
BMA456W

Any motion
No motion
Step detector
Step counter
Step activity
Tap
Single tap
Double tap

BMA456H

Any motion
No motion
Step detector
Step counter
Step activity
Auto low power
Tap
Single tap
Double tap
Triple tap

BMA456MM

Any motion
No motion
Orientation
High-g
Low-g
Significant motion
Auto low power
Tap
Single tap
Double tap
Triple tap

BMA456AN

Any motion
No motion

[GreenBean23]

Hi BSTRobin,

thank you for your quick reply. However, it does not respond to my original question. I didn't ask neither "May I use the sensor API?" nor "What is the BMA456?". Instead, my intent was:

Could you update the official documentation (datasheet, application note), please? (I mean.... features were changed and code was updated, but there is no documentation? Really?)

Where to learn about writing own configuration files?

[BSTRobin]

Hi GreenBean23，

BMA456 has developed many versions of firmware to meet different applications. The example code explains how to use these functions. Users only need to use the example code, and do not care about how to implement the firmware.

[Tomasz_M]

Hi BSTRobin,

I have the same problem, and complaint,  as @GreenBean23 with the documentation vs. github repository mismatch.

Could you please elaborate on each firmware type funcionalities please? Both current readme on GitHub and your previous posts state that BMA456W firmware includes tap (single and double) detection, however the code for W version on github does not state anything about tap configuration. The AN on the website clearlely describes this geature configuration under 0x3C address, but on GitHub 0x3C address is covering wrist wear feature.

I ofcourse assume, that for the GitHub firmware the addresses are stated correct and this is thew way to go for the current "documentation", but my biggest concern is if BMA456W firmware currently supports the tap function? If not this could be at least deleted from README.md to prevent confusion. If it is supported by BMA456W where do I find current documentation for feature configuration?