1.1 Truth Table Inputs
The inputs IN[x] to the LUT can be selected from the
            following sources: 
- Masked
 - I/O Pin
 - Linked LUT
 - Internal Feedback
 - Events
 - Peripherals:
- Analog Comparator output (AC)
 - Timer/Counters waveform outputs (TC/TCC)
 - Serial Communication output transmit interface (SERCOM)
 
 
