Hi mdw;
I checked that the tty1 is used as a Virtual Terminal and is connected as the Console Monitor, the ttyMFD2 is the physical port that is connected to your port. At the end you are using both of them when you are using terminal console with the cable connected in the microUSB port.
The ttyMFD2 is the UART2 and is used for the console terminal communication.
The purpose of your question is in order to find another way to interact with the console terminal? or Why do yo exactly want to use the tty1?
Regards;
CMata