The datasheet on page 55 shows PF0 (SDA) and PF1 (SCL) are the pins for
I2C2, but these pins do not work. Checking the MBED pinout for the
NUCLEO-F429ZI shows:
I2C1: PB8 (SCL) and PB9 (SDA).
I2C2: PB10 (SCL) and PB11 (SDA).
Both of these work and can be scanned and find devices connected to them.
Signed-off-by: Dale Weber <hybotics.sd@gmail.com>.