User`s manual

Troubleshooting
6
Using Reset to Clear a Locked-up
ADM
The following is a list of circumstances which can result in a lock-up condition
between the ADM and your data terminal or PC. Note, there may be other
similar conditions which will cause a lock-up as well.
If you inadvertently issue some Enhanced AT commands, subsequent
commands, or even keypad depressions on the 8500 series display set,
the ADM may ignore or misinterpreted the command. This is because
Enhanced AT applications can be used to monitor and control both voice
and data.
If the receive flow control option in the ADM is set to EIA and your data
terminal or PC does not implement the request to send EIA lead, the ADM
will be permanently in a flow controlled state.
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