Fujitsu F2MCTM-16LX Hardware Manual page 373

Notes:
• When using as the analog input pin, write "1" to the bit of the analog input enable register (ADER5,
ADER6) corresponding to the pin to be used and set to the analog input.
• Setting the analog input pin to ADERx = "0" is disabled. Always set it to ADERx = "1".
• Each analog input pin serves as the general-purpose I/O port and I/O of peripheral function. The pin set
to ADERx = "1" is forcibly set to the analog input pin regardless of the port direction register (DDR5,
DDR6) and the I/O setting of each peripheral function.
CHAPTER 18 8-/10-BIT A/D CONVERTER
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