The MAX32620 I/O pins are capable of providing both 1.8V and 3.3V logic.
To switch between the two levels there a per-pin-function in place. Use the following Arduino code to switch:
- useVDDIO(<pin-number>) to set the pin level to 1.8V
- useVDDIOH(<pin-number>) to set the pin level to 3.3V