01-25-2017, 09:35 PM
Nice, you're like me, all about the details. There is an external port for I2C and some onboard headers.
You probably know but just to clarify and for others, any I2C being connected has to be 3.3v like you mentioned. If 5v is mandatory an I2C level shifter inline will work. All the other ports however are 5v, that's why you saw those resistors on A0 pin. They drop the voltage to 3.3 before going into arduino. I did it like that because most sensors available are 5v for the mega.
You probably know but just to clarify and for others, any I2C being connected has to be 3.3v like you mentioned. If 5v is mandatory an I2C level shifter inline will work. All the other ports however are 5v, that's why you saw those resistors on A0 pin. They drop the voltage to 3.3 before going into arduino. I did it like that because most sensors available are 5v for the mega.
