Dear keepers of the Arduino web site,
I humbly ask that you consider the following question.
When comparing board specs here, https://www.arduino.cc/en/Products/Compare
it is apparent that the Micro’s 20 digital I/O pins result from counting the 6 analog pins as digital pins. This is appropriate because the analog pins can be used for digitalWrite, digitalRead, as well as analogRead. The chart says that the Uno provides 14 digital I/O. This does not include the 6 analog pins A0 – A5 which can serve as digital I/O. For the sake of consistency, would it be more accurate to say that the Uno provides 20 digital I/O pins?
The Uno's product description, “It has 14 digital input/output pins (of which 6 can be used as PWM outputs)” might be more accurately written, “It has 20 digital input/output pins (of which 6 can be used as PWM outputs, and 6 can be used as analog input pins). This topic has been discussed before http://forum.arduino.cc/index.php?topic=180144.0 And http://forum.arduino.cc/index.php?topic=128433.0
Thanks for reading.