Brother HL-3450CN - Manual (Page 60)

CHAPTER 3 BEFORE WORKING WITH THE PRINTER
3-4
Note
When you use automatic interface selection, note the following:
•
This function takes a few seconds to work. If you want to speed up
printing, select the required interface manually by using the control panel
to access the SELECT menu in INTERFACE mode.
If you typically use only one interface, we recommend that you select that
interface in the INTERFACE mode. If only one interface is selected, the
printer will allocate the entire input buffer to that interface.