PairGain HiGain-ETSI RS UTU 712, Руководство пользователя

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700-712-100-01, Revision 01 System Configuration
UTU-712 and ETU-762 List 1 May 10, 1999 37
2 Do the following for each interface option to be changed. Table 16 describes the fields and options displayed
in the Config LTU and Config NTU Interface menus.
•
Use the or the key to select the sub-menu item to be changed.
•
Use the to toggle to the appropriate option or type in the correct information, then press
to select the option.
The settings in boldface type in Table 16 are factory default settings.
Table 16. Fields and Options in Config LTU and Config NTU Interface Menus
Field and Options Description
Primary Timing Source
(a)
Selects the source of clock for the HDSL transmit direction. The choices are:
• INT - Internal Oscillator
• EXT - External 2.048 MHz clock (UTU-712 only)
• Nx64k - Nx64k Serial Data port receive clock (TT)
• HDSL - Recovered clock from received HDSL data
Nx64k Port
Interface Type Select the interface standard for serial data port. The options are: V.35, V.36 , X.21, and
RS-530. See Table 17 for details about the interface types.
Data Rate/# of TSs Read-only display of HDSL data rate and corresponding number of time slots (TSs) as set
automatically by TT clock (Nx64K AUTO mode) or by HDSL Payload Rate option in
Config
System Settings menu (MANUAL mode). See Figure 23 on page 34 . Default is 256kbps/4 .
Beginning TS Read-only display of beginning time slot. For these units Beginning TS is always 0 (zero).
Transmit Clock Selects the transmit data (SD) clock as External (EXT), Internal Rising Edge ( INT_RISING ) , or
Internal Falling Edge (INT_FALLING). Transmit clock is always EXT if the Timing Source is
Nx64k. For more information, see
“System Timing Circuits” on page 12 .
CTS
DSR
RLSD
Specifies one of three methods the LTU/NTU uses to generate the Clear to Send (CTS), Data
Set Ready (DSR), and Received Line Signal Detect (RLSD) control signals for the V.35/V36
port. The V.35/V.36 port is hardware-configured as DCE. Set each of these parameters to
match the requirements of the application. Choices are:
• STD (standard) - The output control signal follows the ITU standards
• ON (force ON) - Control signal is always ON
• OFF (force OFF) - Control signal is always OFF
LL/RL Selects whether the LTU/NTU responds to (enabled) or ignores (disabled) the Local Loopback
(LL) and Remote Loopback (RL) control signals. When enabled
( ENA ), the status of local and
remote loopbacks appears on the Test display.
(a) Primary Timing Source automatically sets to Nx64k in Nx64K AUTO mode.
Table 17. V.35/V.36/X.21 Output Control Signal Operation
State Condition Control Signals Output Data
1 HDSL link down CTS = OFF DSR = DTR
(a)
RLSD = OFF TM = OFF
RD = all ones
2 HDSL link up CTS = RTS
(a)
DSR = DTR
(a)
RLSD = ON TM = OFF
RD = normal data
3 Self-test or remote unit issued a
loopback away from local unit CTS = (link) DSR = OFF
RLSD = (link) TM = ON RD = (link)
4 Local unit issued any loopback CTS = (link) DSR = ON
RLSD = (link) TM = ON RD = looped data
(a) DTR and RTS are inputs received from the customer’s DTE. RLSD performs as defined in
states 1 and 2.
↑↑↑↑ ↓↓↓↓
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