Intel AIMB-253 - Manual (Page 53)

43 Chapter 3 BIOS Setup
Serial Port Setting
Figure 3.8: Serial Port Setting
Onboard Serial Port 1 / 2 / 3 / 4 / 5
Select an address for Serial Port 1/2/3/4/5.
Serial Port 1 / 2 / 3 / 4 / 5 Use IRQ
Select a corresponding interrupt for Serial Port 1/2/3/4/5.
Serial Port 2 / 3 Mode
These settings specify the transmission mode of the Serial Port 2 & 3.
RS-422 defines a Balanced (differential) interface, specifying a single,
unidirectional driver with multiple receivers (up to 32). RS-422 will sup-
port Point-to-Point,
Multi-Drop circuits, but not Multi-Point.
RS-485 defines a Balanced (differential) interface, specifying bidirec-
tional, half-duplex data transmission. Up to 32 transmitters and 32 receiv-
ers may be interconnected in any combination, including one driver and
multiple receivers (multi- drop), or one receiver and multiple drivers.