Qwiic Pro Micro uploading freeze when I2C/Qwiic is connected to sensors

Qwiic System
1

I bought a Qwiic Pro Micro last week. The first few times uploading a sketch (VL53L1X and OLED connected via Qwiic cable) the upload had no issues. Now however, if anything is plugged into the Qwiic connector, the upload stalls and just says “Uploading” indefinitely. I can unplug the qwiic connector, upload sketch, the plug it back in and everything works. While this is workaround for breadboard tests, eventually I will have this setup in a housing where I cannot use this “band-aid” workflow, as the USB will be accessible thru a hole cutout, but not the Qwiic connector.

This issue is present no matter the sketch content (even the basic Blink example). I have tried different computers, cables, sensors, verified IDE/port settings and it all seems to point to an issue with the board itself.

Any suggestions?

Thank you,

Chris

2

How long is the qwiic cable that is being used? How many sensors/devices are on the qwiic bus? I’d guess off-hand that you need to disable one set of the i2c pull-ups on the qwiic bus

3

The issue is present if there is 1 sensor or 4. If I use 1 sensor with a 2" qwiic cable, same issue.

4

I’m not sure what it could be; the i2c bus is only tied to the 3.3v https://cdn.sparkfun.com/assets/4/4/f/2 … ematic.pdf and shouldn’t affect uploads over USB in the first place

Was it purchased from us? If so head over to www.sparkfun.com/returns (contact vendor if purchased elsewhere) and we’ll get ya squared away. One solution might be to switch to a different MCU