I am working on Arduino Mega (Arduino in the picture is for reference)
I am a newbie to Arduino world and have a question. I am working on a project where I have to apply a current between two electrodes and measure voltage at all the remaining electrodes (all the electrodes are placed in an electrolyte bath) in the setup. I have attached a picture showing my setup.
Here each of the electrodes is connected to an analog and a digital pin. (Electrode-1: A0-13, Electrode-2: A1-12, Electrode-3: A2-11 etc) Picture attached.
When I want to pass current through electrodes 1 and 2 I am assigning OUTPUT-LOW to the digital pin connected to electrode 1 and Input_pullup for the electrode 2. I am making rest of the electrodes as input and performing the analog read. When I connect the electrode to Digital 1and analog 1 I am getting some numbers. But when I connect the electrode between A0 and digital 13 and trying the same logic I am getting zeros everywhere. Can anyone help me understand the reason why when the pins are connected A0-0, A1-1, A2-2… its working and failing to give anything when connected between A0-13, A1-12 so on??
One more question is when I connect the electrodes between the digital 1-A1 and digital0-A0, I am unable to upload the sketch. What is the reason for this?