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The functional bits of a pad configuration register field are divided into the following five fields:
• '''MUXMODE ''' (3 bits) defines the multiplexing mode applied to the pin. A mode corresponds to the selection of the functionality mapped on the pin with six (0 to 5) possible functional modes for each pin.
• '''PULL ''' (2 bits) for combinational pullup/pulldown configuration:
-> PULLTYPESELECT: Pullup/pulldown selection for the pin.
-> PULLUDENABLE: Pullup/pulldown enable for the pin.
• '''INPUTENABLE ''' (1 bit) drives an input enable signal to the I/O CTRL.
-> INPUTENABLE = 0: Input Disable. Pin is configured in output only mode.
-> INPUTENABLE = 1: Input Enable. Pin is configured in bidirectional mode.
• '''Off mode values ''' (5 bits) override the pin state when the OFFENABLE bit CONTROL. This feature is used for power saving management:
->OFFENABLE: Off mode pin state override control. Set to 1 to enable the feature and to 0 to disable it.
->OFFPULLTYPESELECT: Off mode pullup/pulldown selection.
• '''Wake-up ''' bits (2 bits):
->WAKEUPENABLE: Enable wake-up detection on input. It is also the off mode input enable value.<br> ->WAKEUPEVENT: Wake-up event status for the pin.'''<br>'''
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'''Mode 0 ''' is the primary mode. When mode 0 is set, the function mapped to the pin corresponds to the name of the pin.
'''Mode 1 to mode 6 ''' are possible modes for alternate functions. On each pin, some modes are used effectively for alternate functions, while other modes are unused and correspond to no functional configuration.
'''The safe mode ''' (default mode 7) avoids any risk of electrical contention by configuring the pin as an input with no functional interface mapped to it. The safe mode is used mainly as the default mode for all pins containing no mandatory interface at the release of power-on reset.
<br> NOTE: For most pads, the reset value for the MUXMODE field is 0b111. The exceptions are pads to be used at boot time to transfer data from selected peripherals to the external flash memory.<br> '''(more information)'''
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