15-6 CHAPTER 15: TROUBLESHOOTING
■If you are attempting to make a connection using HST modulation,
make sure that the modem at the other end of the line is HST
compatible, V.32 terbo compatible at 14.4 Kbps, V.32 compatible at
9600 bps, V.22 bis-compatible at 2400 bps, Bell 212A-compatible at
1200 bps, or Bell 103-compatible at 300 bps.
■If none of the above corrects the problem, it's li kel y t hat the qua li ty o f
the phone connection is poor. The variable quality of phone line
connections may be due to any number of conditions in the phone
service's equipment or the current environment. Try several calls, and
if you still can't get through, try calling another device. If the second
device accepts your call, the problem may lie with the device you first
tried to call.
Errors during software download
Try running the SDL program, or performing the XMODEM file transfer, at
a slower serial port rate. If your computer doesn't have a 16550 UART,
set your communications software to use a slower serial port.
You can also try running the program on a different PC. An idiosyncrasy
of an off-brand PC or an uncommon version of DOS may lock up the SDL
program.
If You Still Have Problems
The problems described above are by far the most common ones that
users encounter. If the suggestions we've given don't clear up your
difficulties, try the following:
1Review the Getting Started Guide carefully to see if you've missed
something.
2Call or visit your dealer. Chances are that your dealer will be able to give
you the assistance you need. This is much more efficient (and
time-saving) than returning the product to 3Com Corporation.
3If your dealer can't help you, refer to the Getting Started Guide provided
in this package. This guide lists several importa nt 3Com numbers.
4If you must return your Business Modem to us, the Service Representative
you talk with will give you a Service Repair Order (SRO) number. Products
without an SRO number will not be accepted.