Extend Accelerometer API support

xvision

The current API does not appear to support the following accelerometer features: 

• ±2g/±4g/±8g dynamically selectable full-scale
• Output data rates (ODR) from 1.56 Hz to 800 Hz
• 12-bit and 8-bit digital output

Can you look at including them as part of the next software release?

Laura

Hey xvision,

The iOS API currently supports all of your feature you mentioned above. Please check out the iOS sample app which allows you to dynamically select between all these features.

xvision

Thanks Laura. Actually my only interest is android. I understand you've just released the product but if you intend to support multiple OS you need to provide support to all platforms simultaneously. I didnt see this information in the API documentation so maybe its just needs to updated. Thanks.

Eric

You can configure the accelerometer through the Android API however, there is no builder class to abstract the byte ordering so you'd have to know the config format.  I will be adding the builder class in the next set of API features.

For the time being, you can copy this line of code from the android app to change the sampling rate:

https://github.com/mbientlab/Metawear-SampleAndroidApp/blob/2.1/src/com/mbientlab/metawear/app/AccelerometerFragment.java#L148

The 0x20 value (3rd byte) sets the sampling rate to 50Hz.  You can modify that value by increments of 0x08, decreasing it to 0 increases the sampling rate (100, 200, 400, 800Hz) and increasing it to 0x38 decreases sampling rate (12.5, 6.25, 1.56Hz).  I haven't tested anything past 100Hz but I doubt the Android ble stack would appreciate receiving messages every 5ms or less.

xvision

Thanks Eric, perfect..