AT Commands
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AT*Y Escape Seq. Detection in Sync.
Escape Sequence Detection (i.e. +++) is normally disabled in all synchronous modes. This is
because synchronous data cannot generate silences around the +++. However to diagnose line
performance you need to be able to escape to command mode.
To allow these diagnostics to take place the user may select the *Y1 option before making a
synchronous connection and then attaching a asynchronous terminal to the modem. The user
may then issue +++ as in asynchronous modes to return to command mode.
Options
AT*Y0 ■ Escape Sequence Detection in Sync mode disabled
AT*Y1 Escape Sequence Detection in Sync mode enabled