Can Arduino FIO Analog pins A6 and A7 be used as digital input?

Using Arduino Microcontrollers
1

Can I use the Arduino FIO (this one) pins A6 an A7 as digital inputs? My tests seem to indicate that I cannot, but I wanted to make sure I'm not overlooking something.

I tried to interface an 8-pin keypad using A0-A7. Pins A0-A5 seem to allow usage as digital inputs, but it seems that A6 and A7 are not able to be used as digital in/out pins.
I have tried blinking an LED on pins A6 and A7 and failed.

I have tried referencing pins A6 and A7 as both A6/A7, and 20/21.

2

Take a look at the datasheet. Those 2 pins can only be used as analog inputs. The other analog pins can be used as digital pins.

3

Ah. That explains everything. I've never even looked at the datasheet, I'm going to do that now. Thank you.