CopperOptics 150-1218-02, Руководство пользователя

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Section 150-612-100
Revision 02
Page 7
SF
YELLOW LED indicating that framing pattern of the
signal being received at the HRU’s DS1 input is SF.
ERR
RED LED indicating a DS1 frame error has occurred.
Note the FRM LED remains off if the HRU input
pattern is unframed or if the HiGain-2 FRMG option
is set to its unframed (UNFR) mode.
8.02 VHDSL The lower 40% of the front panel
addresses the following VHDSL
interface features.
OK
GREEN LED that flashes while the VHDSL Loop is
synchronizing with the HLU. A solid green state
indicates that Loop is properly synchronized with the
HLU.
MAR
YELLOW LED indicating that the HRU’s S/N MARgin
on the VHDSL Loop has dropped below the user
defined margin threshold value. This option is set at
the HLU in the System Settings menu of the
maintenance interface system at the RS-232
maintenance port.
ES
RED LED that flashes ever second in which at least
one VHDSL CRC error is detected.
9. OPTIONS
9.01 The HiGain-2 List 1 system has several
special loopback (SPLB) options that are set
at the HLU. Refer to practice # 150-611-100 for
more details. The HRU also has three user options
set by switches located at the back of the unit as
shown in Figure 4. Each switch has two settings as
follows (refer to the block diagram in Figure 2 for
details):
•
I-CPE
0 *: Sets the CPE current to 0 mA..
60: Sets the CPE current to 60 mA to power an
external NID.
•
TLOS-LB
DIS*
: A loss of the T1 XMT signal from the CPE
causes the HLU to transmit the AIS signal towards
the DSX-1 and does not cause the HRU to enter its
logic loopback state.
EN: A loss of the T1 XMT signal from the CPE
forces the HRU to enter its logic loopback state
(TLOS in Figure 5). While in this loopback state, the
HRU transmits the AIS signal towards the CPE and
returns the Network signal back to the Network. The
HLU displays the message TLOS in its 4 character
front panel read-out. This condition remains until a
valid T1 signal is received from the CPE or until a
loopdown command is issued. Note that once the
TLOS initiated loopback has occurred, it can not
reoccur until the CPE T1 signal has been reapplied
and then removed. This “latching” feature prevents
the HRU from oscillating into and out of TLOS
loopback when a loopdown command is issued in
the absence of a T1 signal from the CPE.
Figure 4. HRU-612 Manual Switches