1-26 Technical Information
Table 1-12 Serial Port 2 Addresses and Interrupts
Starting I/O Address
Interrupt Level
Port
3F8
IRQ04
COM1
2F8
IRQ03
COM2
3E8
IRQ04
COM3
2E8
IRQ03
COM4
3F8
IRQ03
COM1
2F8
IRQ04
COM2
3E8
IRQ03
COM3
2E8
IRQ04
COM4
See Section 2, “Setup and Operation,” for information on resetting the port through the
BIOS Setup utility.
Serial interface specifications include:
Baud rate up to 115.2 KB per second
Word length
5, 6, 7, or 8 bits
Stop bit
1, 1.5, or 2 bits
Start bit
1 bit
Parity bit
1 bit (odd parity or even parity).
Serial interface signals are output through the system board’s 9-pin, D-subconnectors. The
connectors are located at the rear of the system unit. Pin locations for the serial interface
connector are shown in Appendix A.
USB Interface
The Universal Serial Bus (USB) ports allows new Plug and Play serial devices to be added
without having to open the system. The system board has two USB ports; one USB
peripheral can be connected to each port. For more than two USB devices, connect an
external hub to either port.
USB features include:
Self-identifying, hot pluggable peripherals
Automatic mapping of function to driver and configuration; the USB determines
system resources for each peripheral and assigns them without user intervention