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 analo gRead() 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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