Note that the internal pull-ups in the AVR pads can be enabled by setting the PORT bits corresponding to the SCL and SDA pins, as explained in the I/O Port section. The internal pull-ups can in some systems eliminate the need for external ones.
The internal pull-ups can in some systems eliminate the need for external ones.
The arduino ecosystem shall be designed robust by default, imho. I would recommend to use the i2c pullups with lower resistor values, ie 2k2-4k7. Most of the users do not possess techniques for debugging such potential hw-related issues.
twi.begin(); // 100 kHz, no pull-ups twi.begin(I2C_100KHZ); // 100 kHz, no pull-ups twi.begin(I2C_400KHZ); // 400 kHz, no pull-ups
APIs - so your message is the existing drivers utilizing old wire lib have to be rewritten for the new lib.