I2C pins for the VL6180 Breakouts

Sensors Distance
1

Hello -

I was planning to use the SDA and SCL pins on an Arduino UNO to interface to the VL6180 Sensor pcb. The hookup guide shows the connection is instead to the A0 and A1 pins of the UNO.

Now the hookup guide for the VL6180 Breakout pcb has the I2C connected to the SDA and SCL pins of the 3.3V Pro Mini.

So here is my question - How does the Arduino code/Library make this determination by either choosing the A0/A1 on the UNO or choosing the SDA/SCL on the 3.3V Pro Mini?

I looked at the following files to see where this is defined, but I’m not seeing it:

a) Sparkfun_VL6180X_demo.ino

b) Sparkfun_VL6180X.h

c) Sparkfun_VL6180X.cpp

d) Wire.h

e) Wire.cpp

Any suggestions, hints whatever would be appreciated.

My setup is working fine between the UNO and the VL6180X Sensor PCB. No issues there - this is just a nagging question for me that I’d at least like to know why… Thanks

2

Disregard my question - Looks like I answered it myself - after reviewing the data specs for the Atmel ATMEGA328 the PC5 and PC4 pins act as SCL and SDA as an alternate pin configuration. Didn’t realize that the SCL and SDA pins on the IOH connector was a direct connection to the PC5 and PC4 pins. So anytime I2C is used, these pins will be active.