Patton electronics 2720/I Series User Manual page 24

Off The Model 2720 is in remote or CO initiated loopback
mode or sending a pattern. Local loopback is disabled.
LocP The Model 2720 is in Local Loopback mode, and is send-
ing a test pattern.
Remote Loop Idle (default)
The Remote Digital Loopback (RDL) test checks the performance
of both the local and remote Model 2720s, as well as the communica-
tion link between them. Data from the local DTE is sent across the
entire communication circuit and looped back to the local DTE.
The Model 2720 Initiating a RL can be in one of the following
states:
Idle No user-controlled loopbacks are active.
TxPr The Model 2720 is sending the preparatory phase pat-
tern lasting for approximately 2 -5 seconds.
WtAk The Model 2720 is waiting for an acknowledgement from
the remote unit. If the remote unit does not respond, the
WtAk message will remain on the screen.
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