I2C on pro micro not working


I had the setup working on an UNO but am not able to get it working on a pro micro.

I went back to basics and only installed the i2c scanner but it keeps comming up with “no I2C devices found”

I used pins 2 and 3 and added 4k1 pull up resistors.

Any ideas?


not getting it to work so used my Uno again. Maybe I fried the ports...

On my Pro Micro, the first pins on the lower left are TX0, RX0, RST and GND. I see that you have only three pins unused there. You might have a different board, but maybe you put the jumpers on GND and D2 instead of D2 and D3.

Hi Aarg, thx for the reply.

I checked the picture I sent and it is hard to see but I do use the 5th and 6th pin

I made a better picture of the board… But I do not have an RST.