IBM 56K Modem, Руководство по установке

Страница: 50 / 68

56K Modem Internet Kit
6-7
Problem
Your communications software fails to initialize the modem
Possible Solution
Your software’s port settings may be incorrect. Make sure the
software’s port settings match those for your modem.
Additional Information about IRQ and COM port conflicts
Each serial device attached to your computer needs its own unique
communication port (COM Port) and interrupt request line (IRQ). Your
modem is configured through software during installation. If any other device
is using the same COM Port or IRQ as your modem, it will cause a conflict.
This can result in system lock-ups or loss of data.
Common Sources of COM Port and IRQ Conflicts:
Serial interface cards or external COM Ports are the most common sources of
COM Port or IRQ conflicts. There are many other devices in your system that
can cause conflicts as well. Sound cards frequently cause conflicts since they
may use up to three IRQs, depending on the card. Other devices can conflict
with your modem, such as SCSI cards, pre-installed modems, or other
peripherals in your system.
External COM Ports:
Most computers come with two external COM Ports (COM1 and COM2). If
you have an external COM2 connector (look on the back of your computer),
you will have a conflict if you install an internal modem using COM2. Even
if nothing is connected to the external port, the COM Port is still reserved for
that Port, unless you disable it in the system BIOS (see below). The reason
this happens is that the external connector uses a serial interface card, which
reserves COM2 and IRQ3 for the external connector.
Disabling the External COM2 Connector:
If you do not plan to use the external COM2 connector, most computers will
let you disable it (consult your computer's user guide or its manufacturer's
technical support). Your internal modem may then be installed using COM2
and IRQ3, if you choose. Modems are not required to be on COM2 and IRQ3,
but we are using this as an example.
Serial Interface/Expansion Cards:
Sound cards, network cards, SCSI/IDE, and other serial interface cards use
COM Ports and IRQs. You may have installed such a card in your computer's