61223424L2-5A Issue 1, December 2003 7
5. FRONT PANEL OPERATION
The front panel contains two pushbuttons. These are
labeled
LOC and REM.
The
LOC pushbutton controls a bidirectional loopback
at the H4TU-R. Pressing the button causes a bidirec-
tional loopback to occur. If the bidirectional loopback is
active, pressing the button a second time will disable the
loopback.
The
REM pushbutton controls a bidirectional loopback
at the H4TU-C. Pressing the button causes a loopback
toward the H4TU-R and network to occur. If the
loopback is active, pressing the button a second time
will disable the loopback.
6. CONTROL PORT OPERATION
The H4TU-R provides a front panel-mounted DB-9
connector that supplies an RS-232 interface for
connection to a controlling terminal. The pinout of the
DB-9 is illustrated in Figure 5.
Figure 5. RS-232 (DB-9) Connector Pinout
The terminal interface operates at data rates from 1.2,
2.4, 4.8, 9.6, and 19.2 kbps. The asynchronous data
format is fixed at 8 data bits, no parity, and 1 stop bit.
NOTE
If a personal computer with terminal emulation
capability is being used, be sure to disable any
power-saving programs. Otherwise, communi-
cation between the PC and the HDSL4 unit
may be disrupted, resulting in misplaced
characters or screen time outs.
Operation
The screens illustrated in the following section apply to
an HDSL4 circuit deployed with the ADTRAN HDSL4
technology. The circuit includes an H4TU-C, up to two
H4Rs and an H4TU-R. Other configurations are
possible (such as use of another vendor's equipment)
and their displays will vary slightly from those shown in
this section.
A terminal session is initiated by entering multiple
spacebar characters which are used by the H4TU-R to
determine the speed of the terminal. Once the speed has
been determined, an HDSL4
Main Menu is presented as
illustrated in Figure 6.
6
7
8
9
1
2
3
4
5
TXD (Transmit Data
RXD (Receive Data
SGN (Signal Groun
