I wanted to use the I2C located on the Arduino headers of the Cerbuino, which are pins D0 & D1. But something seems “wrong” with those pins : there are no pull-up resistors on the lines.
But I2C requires pull-up resistors somewhere, either on the master (easiest solution, of course) or on one device. Problem is that many (most of ?) slaves don’t provide these pull-up resistors.
So, even with sofware I2C, it won’t work I think. This would mean that I wouldn’t be able to use the Arduino headers to drive I2C devices. Am I wrong, here ?
The IO60P16 is somewhat an exception as it includes the resistors.