Communications Settings; Changing Modem Addresses - IBM Aptiva Hardware Handbook

Communications settings

The built-in modems in IBM Aptiva PCs are preset to
COM1 SERIAL PORT 1. The addresses and interrupts
supported by your computer are:
Address
COM1 3F8
COM2 2F8
COM3 3E8
COM4 2E8
The built-in external serial ports on the back of your
computer support these addresses and interrupts.
Port Address
Serial A 3F8
3E8
Serial B 2F8
2E8
Interrupt
IRQ 4
IRQ 3
IRQ 4
IRQ 3
Interrupt
IRQ 4
IRQ 3
Conflicts may arise if you add adapter cards with serial
ports or if you change the address settings on your
modem. You can resolve most of these conflicts by
using the Configuration/Setup Utility to change serial
port addresses. See "Working with the Configuration/
Setup Utility" on page 61 for more information.

Changing modem addresses

The modem address in your communications software
must match the address setting on your modem. For
example, if the modem address in the software is
COM1 3F8, the DIP switches or jumpers on your modem
must also be set for COM1 3F8. Help messages in your
modem software will help you change your software
address. The information below will help you set the DIP
switches or jumpers on your modem correctly.
To change the hardware address settings on a built-in
14,400 bps data modem, locate the six DIP switches
on the modem bracket on the back of the computer. Use
the chart printed on the modem bracket to set the DIP
switches for the correct address.
Communications settings 27