How to set pin mode if you have both analog and digital inputs & outputs

Using Arduino Programming Questions
#1

Hey guys,
I would like to know how I can set pin mode if I have both analog and digital pins. For example:

int tempPin = 2; // which is analog pin 2
int redPin = 2; // which is digital pin 2
int greenPin = 3; // which is digital pin 3

void setup()
{
pinMode(tempPin, INPUT);
pinMode(redPin , OUTPUT);
pinMode(greenPin , OUTPUT);
}

The problem is, since tempPin is analog pin 2 and also redPin is digital pin 2. Will arduino itself know which is analog pin 2 and digital pin 2. Or is there a way to set pin mode.

Thanks.

#2

You only need to set the pinMode for a Analog pin when you want to use it as a Digital I/O.

If you want to use it as a Digital I/O use the aliases "A0, A1, A2..". The compiler will convert those to the correct pin numbers, e.g. 14, 15, 16 on the Uno.

#3

Can you give me an example on how to set Analog pin as a digital i/o pin.

So, can I write the code as:

int tempPin = 2; // which is analog pin 2
int redPin = 2; // which is digital pin 2
int greenPin = 3; // which is digital pin 3

void setup()
{
pinMode(A2, INPUT);
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
}

#4

Can you give me an example on how to set Analog pin as a digital i/o pin.

For output on A0 use

pinMode(14, OUTPUT);

or

pinMode(A0, OUTPUT);

For digital input on A1 use:-

pinMode(15, INPUT);

or

pinMode(A1, INPUT);
#5