BNO055 communication failure after reset

[jbthompson]

Overview:

BNO055 fails to communicate after we reset it using nReset

Details:

1. half our BNO055 fail to communincate AFTER we successfully read any data from the BNO055 and then do a reset using the nReset pin (low, wait 100 ms, then high, wait 1000 ms)

2. if we reset the BNO055 BEFORE any communication we see NO issues

3. the other half of our boards work just fine and we can read IMU data as well as reset boards after communication

4. we experience this issue using UART and I2C mode on the bad boards

5. if we don't reset the BNO055, AFTER reading / writing some data to the BNO055,  then we see NO issues

6. we believe this issue was not present in the beginning (after we first fabbed our boards) but appeared over time

See schematic:

Note: We were told that the issue could be PS0 and PS1 being pulled up / down with resistors but we just made those 0 ohm jumpers on the bad boards and still see the issue

[o_o]

Hi jbthompson,

I believe that you are facing the same issue as this other BNO055 thread.

[jbthompson]

Hi, thank you this does seem to align with what we are seeing.

However:

1. out of the 4 BNO055 we have, only 2 exhibit this issue, the other two reset just fine (every time) even though we have no external crystal

2. the 2  buggy BNO055 seem to reset just fine the first time around, but after a second reset fail

Is this still consistent with the clock bug? Is that bug consistent or intermittent?

Thank you.