esp32 C3 I2c error through 8,9 pins

[wleagle]

I have a esp32 C3 mini dev board, and it worked well before. Recently I used it to read distance from VL53L1x laser module through I2c port, however it always report errors and cannot detect i2c devices. I was using arduino framework and wire library , gpio 8 for sda and gpio 9 for scl. I also used a logic analyzer and find that they generated very unstable pulses. Yesterday I tried other gpios, interestingly every pair of gpios worked well except 8 and 9. Is this an hardware issue? I guess something wrong with their timing?

[polyakbalazs]

Hi!

I don't know the exact pin numbering of your development board, but it is suspicious for me.

On page 10 of the ESP32-C3-MINI-1 datasheet (https://www.espressif.com/sites/default ... eet_en.pdf) pin 8 and pin 9 are EN and NC, respectively.

This may be not true, but it needs some further research.

Did the board ever work with these 2 pins?

Have you measured them with your I2C device connected to the board? Other pins worked with the external device or only with the logic analyzer?

If you could help me out with these information I may have some other ideas about the problem, let's see!