Apple LaserWriter 12/640 PS - Manual (Page 16)

Connecting the printer
You can connect the printer to many computers and networks using the
printer’s LocalTalk, Ethernet, and parallel ports. The printer prints only one
user’s job at a time, but it manages incoming print jobs from all ports so that
no printing conflicts or problems occur. Unless you specify otherwise, it
also automatically senses which printer language—PostScript or PCL5—the
job requires.
Note: If you are connecting the printer to a network with routers that
combine LocalTalk and EtherTalk into one logical zone, only one printer port
should be connected to the network. Apple recommends Ethernet.
Port Network protocols Computer
LocalTalk AppleTalk Mac OS
Ethernet AppleTalk (EtherTalk) Mac OS
Novell NetWare Windows
Novell ATPS Mac OS
TCP/IP UNIX
Parallel — Windows and DOS
Communication switch
Parallel port
LocalTalk
port
Ethernet port
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