Section 150-319-124
Revision 03
Page 7
5. SYSTEM OPTIONS
5.01
The HLU-319, List 2D contains a non-volatile
RAM (NVRAM) which stores the system options
settings. No dip-switches or jumpers are required to
configure these system options. They are set via
push buttons on the front panel or through the RS-232
interface or from the Network Management interface.
The System Settings are retained if shelf power is lost
or if the HLU-319, List 2D is unplugged. Table 1 lists
the HLU-319, List 2D System Options. Figure 10 and
Figure 22 illustrate the same options on the HLU-319,
List 2D non-doubler and doubler System Settings
Menu screens, respectively. In the System Settings
Menu (which is identical for both non-doubler and
doubler applications), the settings shown represent
the factory default settings.
5.02
The Setup momentary push buttons (Mode
and SEL) are used to set the options from the HLU-
319, List 2D front panel. To initiate the Options
Setting mode, press the Mode button, for at least one
second, but less than three seconds, and release.
The message displayed on the front panel alternates
between the first system parameter and its current
setting. Pressing the SEL button scrolls the display
(one at a time) through all possible settings of the
parameter being displayed. After the desired setting
has been selected, press the Mode button. This
updates the currently displayed mode to the selected
setting, then selects the next configurable parameter.
After the last parameter has been selected, the
display shows “CONF NO (Confirm? (Yes/No)).” If
the Mode button is pressed at this time, none of the
changed parameters are installed. If the SEL button
is pressed, a “YES” message is displayed, and the
selected changes are installed. In either case, the
display returns to its normal mode. The display also
returns to its normal mode, without installing any new
changes, if, after 30 seconds, neither button is
pressed.
5.03
All 14 user options can be set to the factory
default values by pressing the SEL button for six
seconds until the message “DFLT NO” appears. To
set the default values, press the SEL button while the
“DFLT NO” message is displayed. “DFLT YES” will
be displayed, indicating the factory default values are
now in effect. To terminate the Default mode, without
setting the factory default values, press the Mode
button or do nothing for 30 seconds. The latter
returns the display to its normal state.
5.04
Pressing the Mode button for three or more
seconds causes the display to scroll through the HLU-
319, List 2D software version number, its list number,
the type of frame pattern being received from the
DSX-1, the line code setting of the HLU-319, List 2D,
and all 14 options settings. The line code parameter
is the actual DS1 line code being received by the
HLU-319, List 2D when the DS1 code pattern is set to
Auto. Otherwise, the line code parameter mimics
either of the other two line code settings, AMI or
B8ZS, and is not determined by the received line
code.
5.05
The DS1 line code option should always be
set to conform to the type of T1 service (AMI or
B8ZS) being provided by the HiGain system. The
Auto mode, which can adapt to either AMI or B8ZS,
should only be used in applications that require it
(such as when HiGain acts as a standby circuit to T1
circuits whose line codes are not known or may be
both AMI and B8ZS), because it has the following two
limitations:
1. The Auto mode induces one BPV in the T1
bit stream whenever it switches from AMI
to B8ZS.
2. The Auto mode allows each HiGain end
(HLU and HRU) to set its DS1 mode to the
code it is receiving at its local T1 input
port. This makes each unit’s code
independent of the T1 code, which is sent
from the distant T1 input port. Thus, if the
line codes being received by HiGain are
different in each of the two T1 directions,
the HiGain T1 output codes will not match
their respective T1 input codes at the other
end. This could cause the customer’s
received data to be AMI instead of B8ZS,
and thus violate the one’s density rules by
having excessive zeroes.
5.06
The following three user options can only be
set via the RS-232 terminal interface: Circuit ID, DS0
Blocking, and Margin Alarm Threshold.
