Patton electronic 1088/K - Manual (Page 23)

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dure is changed to one minute. The 511/511E pattern will timeout
after 45 seconds. So if the 511/511E is turned on during a local
loop, the restart procedure is set to one minute, but the 511/511E
pattern will time out after 45 seconds, allowing the framer to begin
seeing framed packets (and not restart the box).
After the 511/511E pattern times out, the ER LED will begin flash-
ing. It will remain this way until the pattern generator switch is
turned off. Note that the data at the local DTE and the remote DTE
are not valid. Because the data is unframed there is no way for the
framer to send this data out to the DTE. This is an important dis-
tinction because other Patton units will send out the 511 pattern.
When the unit is placed into a Mode 2 Local Loop, the 511/511E
pattern generator on the local unit is unavailable for transmission.
Figure 15 on page 22 displays the 511/511E pattern generator,
showing that data path connections are not available. The 511/
511E pattern generator is still available on the remote unit. For
more information on the proper operation of this pattern generator
please refer to the "Remote Digital Loop with 511/511E" section.
Figure 16. Block Diagram Remote Loop
Remote Digital Loop
The Remote Loop uses the EOC channel (an out-of-band signal-
ing channel) to establish the remote link. Upon the RDL switch
being thrown or DTE initiation, a RDL_ON Request signal is sent
to the remote unit. The Remote unit then responds with an RDL
Acknowledge command and the link is established. Data origi-
nates at the local DTE and is looped at the Remote PROCESSOR
back to the Local DTE. Note that the data is also passed through to
the Remote DTE and is not squelched. When a Remote unit enters
RDL, it changes its' Restart timeout to one minute (the reason will
be explain in the RDL with 511/511E section). If the line is discon-
nected, the local unit will Restart (NS led activated) after 4–6 sec-
onds, but the Remote unit will wait for one minute before it
Restarts. Note that the transmit data at the Remote DTE is
ignored. When the switch is thrown or the DTE removes the RDL
request, the local unit will transmit an RDL_OFF Request to the
Remote unit. The local unit will keep its TM led active until this
request has been completely sent out. If the switch is thrown again
Pattern
Gen/Det
Loop
Contr ol
Loop
Contro l
Pattern
Gen/Det
Processor Processor
Framer Framer Line