SparkFun Forums

[swithers]

I'm having trouble using the OLA Dev-16832 to read data from the SHTC3 board when it is connected to the 8 channel qwiic max breakout board. It will read it ONLY when plugged directly into the OLA qwiic port. I read that its address is 0x70 which seems to be the same as the mux board, but don't know if that's a problem or not, since the max board should give it another port number, but...? I'm trying to read data from two MPR0025MPA MicroPressure sensors and the SHTC3 at the same time, but it just will not work. Tried different cables, different ports on the Mux board. Interestingly, some ports make the OLA give me the error "Known I2C address but device failed identification at address 0x70" while others don't recognize the SHTC3 is even there. What am I missing?

Thanks

[PaulZC]

Hi @swithers,
This is (hopefully) easy to fix... Each device on the I2C bus needs a unique address, so the clash between the mux and the SHTC3 is a problem. But you can change the address of the mux using the three solder split pads. Please change the address to something else and it should start working.
Just for reference, the mux is 'dumb'. Think of it as a multi-channel 'switch' rather than a true mux. It can open and close all eight ports individually, but cannot do more than that. It does not allocate addresses. In the OLA code, we open the ports one at a time, poll the devices, and then close the port before moving on to the next.
Let me know if this fixes your problem.
Best wishes,
Paul

[swithers]

Thank you @PaulZC !! I jumpered the ADR 0 pads so the mux board is now 0x71 and the SHTC3 is now showing up as 0x70. Thank you!