Can I use the special/dedicated pins for GPIO (MKR1000)

Official Hardware MKR Family MKR 1000 WiFi
1

I'm new to the MKR1000.

  1. I've set pinMode(9,INPUT), but for some reason it's reading HIGH even though I don't have anything attached to it. That confuses me. I've also tried pinMode(9,INPUT_PULLUP).

Is it possible that Pin 9 is reading high because it's the SCK pin? I'm not using MOSI/SCK/MISO at all in my software. But do I need to disable MOSI/SCK/MISO off in the software to use D8, D9, and D10 as normal digital pins? (I assumed they were normal digital pins unless I started using them for MOSI/SCK/MISO in the software)

  1. Likewise, can I use D11 and D12 as normal digital pins (assuming I don't use them for SDA/SCL in my code)?

  2. And, same sort of question, can I use A0 as a normal analog pin, or can it only be used for DAC0?

Thank you for your help in getting me more familiar with the MKR1000.

2

See the reference for general Arduino pin use here

As you will see it depends on how you defined the pin in the first place.
They can "float" if unused.

By adding an LED to whatever pin you choose you will be able to see the results of high and low using the BLINK sketch and defining the pin you have the LED on.

Yes A0 can be used as a regular analog pin. Some functions of pins depend on libraries so if you wanted you could also use them for extra serial communications too.

Mostly it is how it is called and what is connected that makes the most difference to a pins use as they can be very flexible in that regards.

3

OK. Got it. Thank you.