IBM 5500-01E, Operational, Installation, And Maintenance Manual

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- TR (or DTR) on indicates a good connection between the 5500 Control
Unit and the modem.
• Repeat the above checks to make sure there is a good connection between
the host and it’s modem.
5500 Control Unit’s Communication Lines
If the “No Connection” condition persists, the problem could be with the
specific Communication Line in use. Switch the modem cable to the other
5500 Control Unit’s line, and reconfigure the 5500 Control Unit to use the
other WAN port. If this switching of the modem cable resolves the problem,
IBM recommends that you replace your 5500 Control Unit.
Configuration Problems
For configuration problems, check the following parameters:
5500 Control Unit Configuration
• Has the correct port been configured? Configure WAN 0 for modems
attached to “Communication Line 0” and WAN 1 for modems attached to
“Communication Line 1”.
• Has the WAN port been enabled? If you did not specify “Y” for enable,
the interface is not being used.
• Is the correct phone number being used to contact the host? If necessary,
use a regular phone to verify that the host modem answers the phone and
starts its answer tones.
• Does your modem support the Baud Rate specified at the 5500 Control
Unit?
• Insure that the settings for Parity, Data Bits and Stop Bits are the same for
both the 5500 Control Unit and the Host.
• Is the Flow Control consistent for both the 5500 Control Unit and the
Host and does your modem support this control?
• Have you specified the correct modem manufacturer when you selected
the modem setting?
• If you specified an Over-ride Initialization String for the modem, is this
string correct?
• Is the Host’s User ID and Password correct? If not, a connection may be
established, but then dropped after the host fails to authenticate the 5500
Control Unit.
• Is the Authentication setting (Encrypted verses Any) what the host is
expecting?
• A 5500 IP address is required for SLIP (and is optional for PPP). Is the
value specified correct?