Daisy-chaining two SparkFun VR IMU Breakout - BNO080 (Qwiic) boards

Sensors IMU & Motion
1

Hi,

We are attempting to have one microcontroller communicate with two of the BNO080 IMU Boards (SEN-14686) over one I2C bus. We changed the BNO080 I2C address on one of these boards such that its address is 0x4A while the BNO080 on the other board has the default address of 0x4B. We daisy chained these boards together by making use of the Qwicc connectors. We also disabled the pullup resistors on one of the two boards. It looks like we are able to communicate with both of these boards, but it occasionally stops working. So, we are wondering if this daisy-chaining is recommended or not. The following note appears at the end of the description for this board:

NOTE: The I2C address of the BNO080 is 0x4B and is jumper selectable to 0x4A. A multiplexer/Mux is required to communicate to multiple BNO080 sensors on a single bus. If you need to use more than one BNO080 sensor consider using the Qwiic Mux Breakout.

Does this mean that even though our two BNO080s have different I2C addresses, we need to use a multiplexer?

Thanks for your help.

John

2

Hi John. Not sure why they put that on the description!

As long as both have unique addresses, you wouldn’t need a Mux. I’m thinking we intended to say if you had more than two boards, you’d need the Qwiic Mux but if I find out otherwise, I’ll post an update.