KX023 Accelerometer Unresponsive After I2C Configuration

[saeidsobhani]

I don't receive any accelerometer sensor data on my Bangle JS 1 watch.

I was working on a project and used this code to increase the accelerometer data output:

var i2c = new I2C();
i2c.setup({scl:14, sda:15});
i2c.writeTo(0x1E, [0x18, 0b00101100]); // Enter standby mode
i2c.writeTo(0x1E, [0x1B, 0x03]); // Set ODCNTL to 100 Hz
i2c.writeTo(0x1E, [0x18, 0b10101100]); // Return to active mode -

It was working fine, but somehow now there is nothing from the accelerometer chip.

I've tried to read:

WHO_AM_I (0x0F): 0 (I should get 0x15h)
COTR: 0 (should be 0x55h)
CNTL1/CNTL2/ODCNTL: all return 0
The chip won't accept any I2C writes and all reads return 0.

I've tried to write:
Software reset via CNTL2 (0x19, 0x80) - no effect
Multiple reset() commands

Power off and wait for some minutes - no change

Question: Is there a way to recover the accelerometer sensor data?

Any help appreciated!

[bobrippling]

Tagging @gfwilliams

[gfwilliams]

Rebooting the device (long-press BTN1) should help. Some accelerometers allow the I2C address to be configured, and so if you set the wrong thing you can move the accelerometer to a different address - Bangle.js 1 does try and recover that when it reboots though.

Is it possible that you wrote some code that messes with the accelerometer to Flash or storage so it runs at boot, so that even after a reboot it's causing the problem again.

I'd:

• Use Bangle.accelRd to read the accelerometer - instantiating your own I2C instance on those pins might mess things up
• Use the Settings app's 'flatten battery' mode to totally flatten the battery - actually power cycling the accelerometer should fix any misconfiguration that might have happened

[saeidsobhani]

I'm not sure what I have done that led to this, but flattening the battery helped to solve the problem.
Thank you Gordon and Rob