Choosing Fax Software Applications; Communications Settings - IBM Aptiva Hardware Handbook

Fax machines and modems are connected in Groups.
The Group a fax machine belongs to indicates its speed
and level of technological advancement. The original fax
machines were Group 1 machines. These are the slow-
est machines and are almost obsolete today. Faster
Group 2 fax machines replaced the Group 1 machines.
Most fax machines sold today are Group 3 machines.
Generally, a Group 3 fax machine can connect most effi-
ciently to another Group 3 machine and may also be
able to connect to many Group 2 machines. However, a
Group 2 machine cannot connect to a Group 3 machine.
The modem in your computer works with most Group 3
and Group 2 fax machines.

Choosing fax software applications

If your computer did not come with preinstalled fax soft-
ware, you must buy a fax software application to oper-
ate your fax modem. Also, if you add a fax modem to
your computer, you need to purchase fax software.
You send commands to a fax modem (or the fax portion
of a data modem) using a revised version of the AT com-
mand set. This revised version includes two different
sets of commands: Class 1 and Class 2. Some modems
support one class of command while others support
both. When buying a fax software application, choose
the highest class that your modem supports.
CAS and SENDFAX are two other commonly used com-
note: mand sets. These command sets are not supported by the
built-in modems in IBM Aptiva PCs.
•
If your computer has a 2400 bps built-in modem
with 9600 bps send fax and 4800 receive fax capabil-
ities, your modem supports Class 1 fax commands.
•
If your computer has a 14,400 bps built-in modem
with 14,400 bps send and receive fax capabilities,
your modem supports Class 2 fax commands.

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
Communications settings 29