Apple Power Macintosh 7300 series - PC Compatibility Card - Manual (Page 52)

Configuring the PC serial ports
Your PC Compatibility Card supports two serial ports, COM1 and COM2.
You can assign these ports to Macintosh serial ports (such as the printer or
modem port) or to a text file for later processing. Or you can leave the
ports unassigned.
Note: If you are using the optional PC Serial and Parallel Card to connect a
printer, modem, or other device to the PC environment, you do not need to
configure the Macintosh serial ports. See the manual that came with the PC
Serial and Parallel Port card for additional information.
To assign a PC COM port, open the PC Setup control panel and choose a setting in the
COM1 or COM2 pop-up menu.
52 Chapter 3
Unassigned Macintosh serial port
Macintosh modem port assigned
to COM1 in the PC environment
These are the Macintosh serial ports that can be assigned to
COM1 or COM2 in the PC environment. Serial ports already in
use (either by the Macintosh or the PC) are dimmed.