Analog pins as digital inputs

Projects Programming
1

I read somewhere that not all Arduino Nano analog inputs can be used as digital inputs. I seem to remember A6 as one of them.

Can someone tell me what analog pins to avoid trying to use as digital input, thanks

2

How about reading the documentation?

The Nano has 8 analog inputs, each of which provide 10 bits of resolution (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the analogReference() function. Analog pins 6 and 7 cannot be used as digital pins. Additionally, some pins have specialized functionality:

I2C: 4 (SDA) and 5 (SCL). Support I2C (TWI) communication using the Wire library

https://www.arduino.cc/en/Main/ArduinoBoardNano

3

ZOR2:
Can someone tell me what analog pins to avoid trying to use as digital input, thanks

with Atmega328 based boards providing 6 analog pins (A0...A5) you can use all of the six analog pins the same as digital pins (input or output).

with Atmega328 based boards providing 8 analog pins (A0...A7) you can use the first 6 analog pins (A0...A5)the same as digital pins (input or output).

So no matter whether your Atmega328 board has 6 or 8 analog pins, you always can use 6 analog pins (A0...A5) as digital pins.

But be aware: A4 and A5 on Atmega328 based boards is the I2C bus, so if you want to use A4 and/or A5 for I2C, avoid using the same pins for anything else!

4

Thanks for the link Whandall, had not seen that before.

Thanks jurs, that clears it perfectly..