Datasheet

The Analog only pins
The two pins that sit sort-of inside the body of the Pro Trinket, A6 and A7, are analog input only pins. They're kind of
an 'extra' that you get with the Pro Trinket. These pins cannot be used for LEDs, buttons, servos, etc. They're only for
analogRead() usage!
If you're used to using an Arduino Uno, you may notice that pins #2 and #7 are not available. That's because we use
those two pins for the USB bootloader. They are not available for use and are not broken out.
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