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CHAPTER 5: Troubleshooting
How do I find out if I have any COM
PORTS (communications ports) on
my computer?
First, consult your PC’s owner’s
manual. You can also run a
diagnostics program, if necessary.
I am using a “mouse” on COM
PORT 1. On which COM PORT
should I install my modem?
COM PORTS 1 and 3 share the same
IRQ (Interrupt Request Line) within
the computer. Set your modem to
either of COM PORTS 2 or 4. If you
are using a mouse on COM PORTS
2 or 4, set the modem for COM
PORTS 1 or 3. Make sure that you
disable COM PORT 1 or 3 and IRQ4
from the other serial board.
Can I use the same modem
communications software for both
an internal and external modem?
Yes. The external modem will work
off your serial adapter board.
What causes non-sensical text or
characters to appear on my screen?
How do I correct this problem?
What you see on your computer
screen is referred to as “garbage”.
There are eight common causes:
1
. A conflict with IRQ with other
serial ports.
2
. Initialization is not correct.
Refer to Chapters 3 and 4 of this
manual.
3
. The data rate (baud or bps rate)
of your modem does not match
the rate of the host modem.
4
. The parity bit is not set properly.
5
. The stop bit is not set properly.
6
. The modem is not set to full-
duplex.
7
. If there is hissing on the
telephone line and garbage on
the screen, the telephone line is
most likely the culprit. You have
received a bad connection,
perhaps due to a weather
disturbance. Disconnect the call
and try again.
8.
The modem may be defective.
5. TROUBLESHOOTING
