Yep. You can also look at the pin definitions in the variant.cpp file:
....\arduino-1.5.6-r2\hardware\arduino\sam\variants\arduino_due_x\
Lines 153 (pin 17) and 160 (pin 20). Also, to manipulate your pin, you should consider some definitions. For example:
-If pin will be used as pure output, use PIO_OUTPUT_O instead of PIO_DEFAULT.
-If pin will be used as pure input, use PIO_INPUT instead of PIO_DEFAULT.
-If pin needs internal pull-up, use PIO_PULLUP instead of PIO_DEFAULT, etc..
and depending of the nature of your application, you will need to choose the right peripheral (function). For example,
by default, pin A5 works as:
- Analog input if configured with peripheral X1 (extra function).
- Timer clock if configured with peripheral A.
- Input external wait signal with peripheral B.
CAVEAT: I use to catalog the info above as part of Due's 'deep waters', so be very careful if you decide to use it and mess with it.
p