Paradyne Appliance Trim Kit 727 User Manual

AREA CODE CHANGE  
Please note that the area code for  
Paradyne Corporation in Largo, Florida  
has changed from 813 to 727.  
For any Paradyne telephone number that  
appears in this manual with an 813 area  
code, dial 727 instead.  
 
Copyright E 1997 Paradyne Corporation.  
All rights reserved.  
Printed in U.S.A.  
Notice  
This publication is protected by federal copyright law. No part of this publication may be copied or distributed,  
transmitted, transcribed, stored in a retrieval system, or translated into any human or computer language in any form  
or by any means, electronic, mechanical, magnetic, manual or otherwise, or disclosed to third parties without the  
express written permission of Paradyne Corporation, 8545 126th Avenue North, P.O. Box 2826, Largo,  
Florida 33779-2826.  
Paradyne Corporation makes no representation or warranties with respect to the contents hereof and specifically  
disclaims any implied warranties of merchantability or fitness for a particular purpose. Further, Paradyne Corporation  
reserves the right to revise this publication and to make changes from time to time in the contents hereof without  
obligation of Paradyne Corporation to notify any person of such revision or changes.  
Changes and enhancements to the product and to the information herein will be documented and issued as a new  
release to this manual.  
Trademarks  
All products and services mentioned herein are the trademarks, service marks, registered trademarks or registered  
service marks of their respective owners.  
Warranty, Sales, and Service Information  
Contact your sales or service representative directly for any help needed. For additional information concerning  
warranty, service, repair, spare parts, installation, documentation, or training, use one of the following methods:  
H Via Telephone: Call our automated call system to receive current information via fax or to speak with a  
company representative.  
— Within the U.S.A., call 1-800-870-2221  
— International, call 813-530-2340  
Printed on recycled paper  
March 1997  
7510-A2-GB20-00  
A
 
 
Contents  
H
H
H
1
2
H
H
H
H
H
H
3
H
H
7510-A2-GB20-00  
March 1997  
i
 
Contents  
4
5
6
H
H
H
H
H
H
H
H
H
H
H
H
H
H
March 1997  
7510-A2-GB20-00  
ii  
 
Contents  
H
H
H
H
H
H
H
H
H
H
H
7510-A2-GB20-00  
March 1997  
iii  
 
About This Guide  
Document Purpose and Intended Audience  
This guide contains information needed to set up, configure, and operate the  
Model 7510 DSU and is intended for installers and operators.  
Document Summary  
Section  
Description  
About the DSU. Describes the DSU features and shows  
examples of typical configurations.  
Using the Asynchronous Terminal Interface. Provides  
instructions for accessing the user interface and navigating  
the screens.  
Customizing the DSU. Provides procedures for setting up  
the user interface and DSU configuration.  
Monitoring the DSU. Describes monitoring details about the  
LEDs, DSU status, and network statistics.  
Testing. Provides details about available tests and test  
setup.  
Messages and Troubleshooting. Provides information on  
device messages and troubleshooting.  
Configuration Option Tables. Contains all configuration  
options, default settings, and possible settings.  
Worksheets. Contains all the configuration options, default  
settings, and possible settings to use for planning.  
Cables and Pin Assignments. Contains connector and  
interface details.  
Technical Specifications. Contains physical and regulatory  
specifications of the DSU.  
7510-A2-GB20-00  
March 1997  
v
 
       
About This Guide  
Section  
Description  
Defines acronyms and terms used in this document.  
Lists key terms, acronyms, concepts, and sections in  
alphabetical order.  
Product-Related Documents  
Document Number  
Document Title  
7510-A2-GN10  
Model 7510 DSU Startup Instructions  
March 1997  
7510-A2-GB20-00  
vi  
 
 
About the DSU  
1
Model 7510 DSU Features  
The DSU provides an interface between the customer premises equipment (CPE)  
and a Digital Data Service (DDS) network.  
The DSU’s features and capabilities include:  
H
H
Easy Installation. Connects to your equipment using standard connectors  
and cables.  
Easy Configuration. A compact and well-thought set of configuration options  
minimizes your customization effort.  
H
H
DDS Operation. Operates at 56 and 64 kbps CC (clear channel).  
Local Area Data Set (LADS) Operation. Operates at 56 and 64 kbps  
full-duplex as a limited-distance modem.  
H
H
H
Autorating. Automatically adjusts to the detected line rate.  
Data Port Rates. Automatically adjusts to the DDS or LADS operating rates.  
Asynchronous Terminal Interface (ATI). Provides a menu-driven  
VT100-compatible interface for configuring and managing the DSU.  
Local Management. Provides local management using an asynchronous  
terminal connection through the Terminal port.  
Remote Management. Provides remote management using an external  
modem through the Terminal port.  
H
H
Diagnostics. Lets you diagnose device and network problems with digital  
loopbacks and pattern tests.  
Device and Test Monitoring. Lets you track and evaluate the unit’s  
operation with status and test result information.  
7510-A2-GB20-00  
March 1997  
1-1  
 
     
About the DSU  
Typical DSU Configurations  
The following illustration shows a typical LAN/WAN interconnection application for  
the DSU. The routers connected to the DSU at each location provide the LAN  
interconnection.  
DDS  
Network  
Router  
Router  
DSU  
DSU  
497-15084-01  
The DSU can also be used in a Frame Relay network.  
Frame  
Relay  
Network  
Router  
Router  
DSU  
DSU  
497-15271  
Two DSUs can be connected back-to-back to act as Local Area Data Sets.  
56 Kbps  
Router  
Router  
DSU  
DSU  
497-15236  
March 1997  
7510-A2-GB20-00  
1-2  
 
 
About the DSU  
User Interfaces  
There are two types of user interfaces for the DSU:  
H
H
Menu-driven Asynchronous Terminal Interface (ATI) screens (see Using the  
7510 DSU  
TS (105)  
CTS (106D)TR (108)  
OK  
ALARM TEST DM  
OOS  
OOF  
NS  
TXD (103R)XD (10R4)  
Port  
System  
Network  
56/64K  
497-15245  
Rear Panel Interfaces  
The following illustration shows the physical interfaces of the DSU. Information  
about the installation of the DSU is contained in the Model 7510 DSU Startup  
Instructions.  
Modem  
DTE  
or  
Terminal  
NETWORK  
TERMINAL  
POWER  
D
T
E
Power  
Network  
497-15237  
7510-A2-GB20-00  
March 1997  
1-3  
 
     
Using the Asynchronous  
Terminal Interface  
2
Connecting to the Terminal Port  
The device used for the Asynchronous Terminal Interface (ATI) can be a  
VT100-compatible async terminal, or a PC running emulation software. The  
terminal or PC can be connected to the Terminal port directly, or through an  
external modem.  
Ensure that the device you connect communicates using these settings:  
H
H
H
H
Data rate set to 9.6 kbps.  
Character length set to 8.  
Parity set to None.  
Stop Bits set to 1.  
Terminal port settings cannot be changed from the ATI.  
7510-A2-GB20-00  
March 1997  
2-1  
 
     
Using the Asynchronous Terminal Interface  
Initiating an ATI Session  
The user interface is blank until activated. Press Return to activate the user  
interface. The first time you do this the Main Menu screen is displayed.  
main  
Device Name:  
Model: 7510  
MAIN MENU  
Status  
Test  
Configuration  
Control  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
Ctrl-a to access these functions Exit  
Entry to all of the DSU’s tasks begins at the Main Menu screen, which has four  
menus or branches.  
Select . . .  
To . . .  
Status  
View results of diagnostic tests, network status of interfaces, statistics,  
LEDs, and DSU identity information.  
Test  
Select and cancel tests for the DSU’s interfaces.  
Configuration Display and edit the configuration options.  
Control  
Establish identification for the DSU and system, or to initiate a power-up  
reset of the DSU.  
March 1997  
7510-A2-GB20-00  
2-2  
 
   
Using the Asynchronous Terminal Interface  
MAIN MENU  
Status  
Test  
Configuration  
Control  
Load  
Configuration  
From...  
Test  
Configuration  
Control  
Status  
Edit/Display  
System  
Network Tests  
Data Port Tests  
Lamp Test  
System and Test Status  
Network Interface Status  
Device Name  
Reset Device  
Network  
Network Performance  
Statistics  
Data Port  
Terminal Port  
Abort All Tests  
Display LEDs  
• Identity  
497-15238  
Screen Format Types  
Three types of screen formats are available on the ATI.  
Use the screen format . . . To . . .  
Menu selection  
Input  
Display a list of available functions for user selection.  
Add or change information on a screen.  
Input or edit fields that have an Underline in the field value  
Display  
Display configuration information and results from  
performance and DSU-specific tests.  
Display-only fields that have no underline in the field value.  
What Affects Screen Displays  
What appears on the screens depends on the:  
H
H
Current configuration – How the DSU is currently configured.  
Data selection criteria – What you entered in previous screens.  
7510-A2-GB20-00  
March 1997  
2-3  
 
   
Using the Asynchronous Terminal Interface  
Screen Work Areas  
There are two user work areas:  
H
Screen area – This is the area above the dotted line that provides the menu  
path, menus, and input fields.  
The menu path appears as the first line on the screen. In this manual, the  
menu path is presented as a menu selection sequence with the names of the  
screens:  
Main Menu Configuration (Load Configuration From) →  
Configuration Edit/Display Data Port Options  
H
Screen function key area – This is the area below the dotted line that lists  
function keys specific to the screen, field value choices, and system  
messages.  
Menu Path  
main/configuration/edit/port  
Device Name: Node A  
Model: 7510  
DATA PORT OPTIONS  
Invert Transmit Clock:  
Disable  
Port (DTE) Initiated Loopbacks: Disable  
Bilateral Loopback:  
Carrier Control by RTS:  
CTS Control:  
RLSD Control:  
DSR Control:  
Disable  
Constant  
Standard  
Standard  
Standard  
Enable  
Input Fields  
Monitor DTR:  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
Ctrl-a to access these functions, ESC for previous menu  
Save  
Select: Disable, Enable  
MainMenu  
Exit  
Screen  
Function  
Keys  
No Signal  
System  
Messages  
Field Value  
Choices  
March 1997  
7510-A2-GB20-00  
2-4  
 
   
Using the Asynchronous Terminal Interface  
Navigating the Screens  
You can navigate the screens by:  
H
H
H
Using keyboard keys  
Using screen function keys  
Switching between the two screen work areas  
Keyboard Keys  
Use the following keyboard keys to navigate within the screen.  
To . . .  
Press . . .  
Move cursor between the screen area and the screen function  
keys area below the dotted line at the bottom of the screen  
Ctrl-a  
Return to the previous screen  
Esc  
Tab  
Move cursor to the next field on the screen  
Accept entry or display valid options on the last row of the screen Return (Enter)  
when pressed before entering data or after entering invalid data  
Move cursor to the previous field  
Ctrl-k  
Select the next valid value for the field  
Spacebar  
Delete character that the cursor is on  
Delete (Del)  
Up Arrow or Ctrl-u  
Move cursor up one field within a column on the same screen  
Move cursor down one field within a column on the same screen Down Arrow or Ctrl-d  
Move cursor one character to the right in a text field  
Move cursor one character to the left in a text field  
Right Arrow or Ctrl-f  
Left Arrow or Ctrl-b  
Ctrl-l  
Redraw the screen display, clearing information typed in but not  
yet entered  
" Procedure  
To make a menu or field selection:  
1. Press the tab key or the right arrow key to position the cursor on a menu or  
field selection. Each selection is highlighted as you press the key to move the  
cursor from position to position.  
2. Press Return. The selected menu or screen appears.  
3. Continue Steps 1 and 2 until you reach the screen you want.  
7510-A2-GB20-00  
March 1997  
2-5  
 
     
Using the Asynchronous Terminal Interface  
The current setting or value appears to the right of the field name. The valid  
choices for the field are displayed in the screen function area. You can enter  
information into a selected field by typing in the first letter or letters of a field value  
or command.  
If a field is blank and the Field Values screen area displays valid selections, press  
the spacebar and the first valid value for the field will appear. Continue pressing  
the spacebar to scroll through other valid values.  
Screen Function Keys  
All screen function keys located below the dotted line operate the same way  
(upper- or lowercase) throughout the screens.  
For the screen  
Select . . . And press Return to . . .  
function . . .  
MainMenu  
Exit  
M or m  
E or e  
S or s  
R or r  
C or c  
Return to the Main Menu screen.  
Terminate the async terminal session.  
Save information.  
Save  
Refresh  
ClrStats  
Update screen with current information.  
Clear network performance statistics and refresh the  
screen.  
PgUp  
U or u  
D or d  
R or r  
Display the previous page.  
PgDn  
Display the next page.  
ResetMon  
Reset an active Monitor 511 test counter to zero.  
March 1997  
7510-A2-GB20-00  
2-6  
 
   
Using the Asynchronous Terminal Interface  
Switching to the Screen Function Key Area  
Selecting Ctrl-a allows you to switch between the two screen work areas to  
perform all screen functions.  
" Procedure  
To access the screen function area below the dotted line:  
1. Press Ctrl-a to switch from the screen area to the screen function key area  
below the dotted line. The available selections for the first input field appear  
on the last line as shown below.  
2. Select either the function’s designated (underlined) character or press the tab  
key until you reach the desired function key.  
Example:  
To reset the Monitor 511 error counter to zero, type r or R (ResetMon).  
3. Press Return. The function is performed.  
4. To return to the screen area above the dotted line, press Ctrl-a again.  
main/test/network  
Device Name:  
Model: 7510  
NETWORK TESTS  
Status  
Test  
Command  
Result  
0:00:00  
CSU Loopback:  
DSU Loopback:  
Start  
Start  
Inactive  
Inactive  
0:00:00  
Send V.54 Up:  
Send  
Sending  
Send V.54 Down: Send  
Inactive  
Send 511:  
Monitor 511:  
Start  
Stop  
Inactive  
Active  
0:00:00  
125:08:48  
Errors 99999+  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
Ctrl-a to access these functions, ESC for previous menu  
ResetMon  
MainMenu  
Exit  
7510-A2-GB20-00  
March 1997  
2-7  
 
   
Using the Asynchronous Terminal Interface  
Ending an ATI Session  
Use the Exit function key from any screen to terminate the session.  
" Procedure  
To end an ATI session:  
1. Press Ctrl-a to go to the screen function key area below the dotted line.  
2. Save changes if required. A confirmation message appears if you have made  
but not saved changes to your configuration.  
3. Tab to Exit (or type e or E) and press Return. The User Interface Idle screen  
appears.  
March 1997  
7510-A2-GB20-00  
2-8  
 
   
Customizing the DSU  
3
Identifying the Device and System  
Use the Device Name screen to determine the name that will be displayed at the  
top of all ATI screens, and system information that will be displayed on the  
Identity screen. To access the Device Name screen, follow this menu selection  
sequence:  
Main Menu Control Device Name  
main/control/device name  
Device Name:Node A  
Model: 7510  
DEVICE NAME  
Device Name:  
System Name:  
System Location:  
System Contact:  
Node A  
Clear  
Clear  
Clear  
Clear  
________________________________________  
________________________________________  
________________________________________  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
Ctrl-a to access these functions, ESC for previous menu  
Save  
MainMenu  
Exit  
Fields on the Device Name screen are null until you enter values. Allowable  
values are any printable ASCII character. ASCII printable characters include:  
H
H
H
H
Numeric 0–9  
Upper or lower case A–Z  
Space  
All ASCII symbols  
Use the left and right arrow keys to scroll through the fields. Select Clear to reset  
a field to a null value.  
7510-A2-GB20-00  
March 1997  
3-1  
 
     
Customizing the DSU  
" Procedure  
To enter Device Name screen information:  
1. Position the cursor in the Device Name field. Enter a name unique in your  
system to identify the unit.  
The maximum length of Device Name is 20 characters.  
2. Position the cursor in the System Name field. Enter a name unique in your  
network to identify the system.  
The maximum length of System Name is 127 characters.  
3. Position the cursor in the System Location field. Enter the physical location of  
the system.  
The maximum length of System Location is 127 characters.  
4. Position the cursor in the System Contact field. Enter the name and contact  
information for the person responsible for the unit.  
The maximum length of System Contact is 127 characters.  
5. Save the Device Name screen information as shown in the next section.  
Saving Configuration Options  
When changes are made to the configuration options, the changes must be  
saved to take effect. Use the Save key or Save Configuration screen.  
" Procedure  
To save configuration options changes:  
1. Press Ctrl-a to switch to the screen function key area below the dotted line.  
2. Select Save and press Return.  
NOTE:  
When Exit is selected before Save, a Save Configuration screen appears  
requiring a Yes or No response.  
If you select . . .  
Then . . .  
Yes  
No  
The configuration is saved.  
The Main Menu appears and changes are not saved.  
March 1997  
7510-A2-GB20-00  
3-2  
 
   
Customizing the DSU  
Configuring the DSU  
Configuration option settings determine how the DSU operates. Use the DSU’s  
Configuration branch to display or change configuration option settings.  
Configuration Option Areas  
The DSU is shipped with factory settings in the Default Factory configuration  
area. You can find default information by:  
H
H
Appendix B.  
Accessing the Configuration branch of the DSU menu.  
The DSU has two sets of configuration option settings. The Current Configuration  
matches the Default Factory Configuration until modified and saved by the user.  
Configuration Option Area Configuration Option Set  
Current Configuration  
The DSU’s active set of configuration options.  
Default Factory Configuration A read-only configuration area containing the factory  
default configuration options.  
If the factory default settings do not support your network’s configuration,  
customize the configuration options for your application.  
Accessing and Displaying Configuration Options  
To display the configuration options, you must first copy one configuration option  
set into the edit area.  
" Procedure  
To load a configuration option set into the configuration edit area:  
1. Follow this menu selection sequence:  
Main Menu Configuration (Load Configuration From)  
2. Select Current Configuration or Default Factory Configuration. Press Return.  
The selected configuration option set is loaded and the Configuration  
Edit/Display menu screen appears.  
7510-A2-GB20-00  
March 1997  
3-3  
 
       
Monitoring the DSU  
4
What to Monitor  
This chapter presents information on how to access and monitor DSU status and  
performance statistics on the DDS network. You can monitor DSU operations by  
viewing:  
H
H
H
H
H
System and Test Status screen  
Highest priority Health and Status message on the last line of all screens  
Network Interface Status screen  
Network Performance Statistics screen  
LEDs on the ATI Status screen or the DSU’s front panel  
Table 4-1 shows the available indicators of alarm conditions on the network  
interface and the User Data port.  
Table 4-1. Alarm Indicator Locations  
Status  
Screen LED  
Specific  
Alarm Condition  
Crossed Pairs  
Y
Y
Y
Y
Y
Y
N
Y
Y
Y
N
N
No Signal (NS)  
Out of Service (OOS)  
Out of Frame (OOF)  
Excessive Bipolar Violations (BPV)  
Inband Framing Error  
7510-A2-GB20-00  
March 1997  
4-1  
 
     
Monitoring the DSU  
Viewing System and Test Status  
To view System and Test Status information, follow this menu selection  
sequence:  
Main Menu Status System and Test Status  
The System and Test Status screen has three sections:  
H
H
H
Health and Status – Displays messages in priority order (highest to lowest).  
Self-Test Results – Results of the Diagnostic test run on the device itself.  
Table 4-4.  
main/status/system  
Device Name:Node A  
Model: 7510  
SYSTEM AND TEST STATUS  
SELF-TEST RESULTS  
HEALTH AND STATUS  
TEST STATUS  
Cross Pair Detection  
No Signal hhh:mm:ss  
Out of Service hhh:mm:ss  
Out of Frame hhh:mm:ss  
Excessive BPVs hhh:mm:ss  
User Data Port DTR Off  
Device Fail yyyyyyyy  
DSU Operational  
Device Fail  
Memory Fail  
Passed  
No Test Active  
CSU Loopback Active  
Network-init. CSU LB Active  
DSU Loopback Active  
Network-init. DSU LB Active  
V.54-initiated DSU LB Active  
Local Loopback Active  
Sending 511 on Port  
Monitoring 511 on Port  
Sending 511 on Network  
Monitoring 511 on Network  
Lamp Test Active  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
ESC for previous menu MainMenu Exit  
Refresh  
Clear  
March 1997  
7510-A2-GB20-00  
4-2  
 
   
Monitoring the DSU  
Health and Status  
The following messages appear in the first column of the System and Test Status  
screen. The highest priority Health and Status message also appears on all ATI  
screens on the bottom right.  
Table 4-2. Health and Status Messages (1 of 2)  
Message  
What Message Indicates  
What To Do  
Cross Pair  
Detection  
The DDS Receive (RX) and  
Transmit (TX) pairs are  
crossed on the network  
interface. Alarm LED is on.  
Reverse the RX and TX pair at the  
punchdown block or other  
termination point.  
No Signal  
hhh:mm:ss  
No signal is being received.  
Local DSU network problem.  
The Alarm and NS LEDs are  
on and Network Performance  
Statistics are active.  
1. Verify that the network cable is  
securely attached at both ends.  
1
2. Contact network provider.  
Out of Service  
hhh:mm:ss  
DSU is receiving out of  
service code from the  
network for the remote unit.  
The Alarm and OOS LEDs  
are on and Network  
Performance Statistics are  
active.  
1. Verify that the remote site is in  
service.  
1
2. Contact network provider.  
Out of Frame  
hhh:mm:ss  
DSU is detecting an out of  
frame condition, associated  
with:  
1. Verify that the line rate matches  
the configured rate.  
1
2. Contact network provider.  
H Receiving out of frame  
code from the network.  
H DSU detecting out of frame  
errors with 64 kbps CC  
data rate.  
H DSU unable to synchronize  
local receiver circuit with  
line signal.  
Excessive BPVs  
hhh:mm:ss  
Data rates do not match or  
network trouble is causing  
bipolar violations. Alarm LED  
is on and Network  
1. Verify that the network cable is  
securely attached at both ends.  
1
2. Contact network provider if  
problem persists.  
Performance Statistics are  
active.  
User Data Port  
DTR Off  
The DTE is not ready to  
transmit or receive data. This that the DTE is powered up and  
message will not appear  
unless Monitor DTR is  
enabled.  
Check on the DTE status. Verify  
asserting DTR.  
1
hhh:mm:ss indicates the amount of time the condition has existed in hours, minutes,  
and seconds. When the maximum time has been exceeded, 255:59:59+ appears.  
7510-A2-GB20-00  
March 1997  
4-3  
 
     
Monitoring the DSU  
Table 4-2. Health and Status Messages (2 of 2)  
Message  
What Message Indicates  
What To Do  
Device Fail  
yyyyyyyy  
An internal error has been  
detected by the operating  
software. yyyyyyyy indicates  
the 8-digit hexadecimal failure  
code.  
1. Provide the 8-digit failure code  
shown (yyyyyyyy) to your service  
representative.  
2. Reset the DSU to clear the  
condition and message.  
DSU Operational DSU is functioning properly  
and there are no status  
No action needed.  
messages to display.  
Self-Test Results  
The results of the last power-up or reset self-test appear in the middle column of  
the System and Test Status screen.  
Table 4-3. Self-Test Results Messages  
Message  
What Message Indicates  
What To Do  
1. Reset the DSU and try again.  
Device Fail  
One or more of the DSU’s integrated  
circuit chips has failed device-level  
testing.  
2. Call your service  
representative for assistance if  
the message reappears.  
Memory Fail DSU failed memory verification.  
Passed  
The DSU has been plugged in or  
reset and has passed the diagnostic  
test. There are no other status  
messages.  
No action needed.  
March 1997  
7510-A2-GB20-00  
4-4  
 
     
Monitoring the DSU  
Test Status Messages  
of the System and Test Status screen.  
Table 4-4. Test Status Messages  
Test Status Message Meaning  
No Test Active  
Status message, indicating no local, remote, or network test in  
progress.  
CSU Loopback Active A CSU Loopback toward the network is currently active.  
Network-init. CSU LB  
Active  
A CSU Loopback initiated by the network is currently active.  
DSU Loopback Active A DSU Loopback toward the network is currently active.  
Network-init. DSU LB  
Active  
A DSU Loopback initiated by the network is currently active.  
H If the network service is 56 kbps, the network loopback is  
non-latching. A non-latching loopback ends when the  
network activation codes stop.  
H If the network service is 64 kbps CC, the network loopback  
is latching. This condition can only occur when the Network  
Interface option Network-initiated DSU Loopback (64K CC)  
V.54-initiated DSU LB A DSU loopback is active that was initiated by the detection of  
Active  
a V.54 sequence originated by the remote unit. This condition  
can only occur when V.54 Initiated DSU Loopback is enabled.  
Local Loopback Active A local loopback toward the DTE is currently active.  
Sending 511 on Port A 511 test pattern is being sent over the DTE port.  
Monitoring 511 on Port DSU is monitoring a 511 test pattern over the DTE port.  
Sending 511 on  
Network  
A 511 test pattern is being sent over the network interface.  
Monitoring 511 on  
Network  
DSU is monitoring a 511 test pattern on the network interface.  
Lamp Test Active  
The Lamp Test is active, causing the LEDs on the front panel to  
light.  
7510-A2-GB20-00  
March 1997  
4-5  
 
       
Monitoring the DSU  
Viewing Network Interface Status  
The network interface status fields are read-only:  
H
Line Rate (Kbps). If the DSU is connected to an operating line and the Line  
Rate (Kbps) shows Autobaud and does not change to a line rate within about  
15 seconds, Line Rate (Kbps) may have to be reconfigured manually. Refer  
H
Loop Loss (dB). The loop loss is the loss of signal strength of the receive line  
signal from the local loop.  
To view the Network Interface Status, follow this menu selection sequence:  
Main Menu Status Network Interface Status  
Table 4-5 describes the contents of the Network Interface Status screen.  
Table 4-5. Network Interface Status Screen Contents  
Field  
Status  
What the Status Indicates  
Line Rate (Kbps)  
56 Kbps  
64 CC  
64 LADS  
Line rate on the network interface.  
Autobaud indicates the DSU is  
trying to determine the network line  
rate. This should be a temporary  
condition.  
Autobaud  
No Signal  
No signal can be detected over the  
network interface.  
Loop Loss (dB)  
0 to 65 dB  
Amount of loop loss – loss of signal  
strength of the receive line signal  
from the local loop, measured in  
decibels.  
Inoperative  
The line may be disconnected.  
March 1997  
7510-A2-GB20-00  
4-6  
 
   
Monitoring the DSU  
Viewing Network Performance Statistics  
Performance statistics for the network interface are available to:  
H
H
Monitor the current status of the network operations.  
View the DSU’s performance statistics, which:  
— Assist you in determining the duration of specific conditions.  
— Provide a historical context for problem detection and analysis.  
To view the Network Performance Statistics, follow this menu selection sequence:  
Main Menu Status Network Performance Statistics  
main/status/performance  
Device Name:  
Model: 7510  
NETWORK PERFORMANCE STATISTICS  
No Signal Count: 101920  
26:33:08  
0:00:00  
8:53:49  
Out of Service Count:  
Out of Frame Count:  
Excessive BPV Count:  
Invalid BPV Count:  
0
621  
99830  
87409  
144:28:11  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
ESC for previous menu MainMenu Exit  
Refresh  
ClrStats  
All counts show the number of occurrences since the last reset of the counters.  
H
H
No Signal Count is the number of occurrences of a No Signal condition.  
Out of Service Count is the number of occurrences of an Out of Service  
(OOS) condition.  
H
H
H
Out of Frame Count is the number of occurrences of an Out of Frame  
(OOF) condition.  
Excessive BPV Count is the number of times at least one invalid bipolar  
violation was detected every 20 ms for a 2-second period.  
Invalid BPV Count is a raw count of the number of invalid bipolar violations.  
In the last column, hhh:mm:ss indicates the amount of time the condition has  
existed in hours, minutes, and seconds. When the maximum time has been  
exceeded, 255:59:59+ appears.  
The screen appears with the cursor in the function area below the dotted line. To  
update the performance statistics, select Refresh and press Return.  
Select ClrStats and press Return to clear all statistics and refresh the screen.  
7510-A2-GB20-00  
March 1997  
4-7  
 
   
Monitoring the DSU  
Monitoring the LEDs  
The status of DSU LEDs can be viewed on the Display LEDs Status screen.  
The 12 LEDs are organized into three groups:  
H
H
H
System LEDs display the status of the unit  
Network LEDs display the status of the network interface  
Port LEDs display the activity on the user data (DTE) port  
To view the LED status screen, follow this menu selection sequence:  
Main Menu Status Display LEDs  
main/status/leds  
Device Name:  
Model: 7510  
DISPLAY LEDS  
SYSTEM  
ALARM TEST  
NETWORK  
DTE  
OK  
DM OOS OOF NS  
TXD  
RXD RTS CTS DTR  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
ESC for previous menu MainMenu Exit  
Refresh  
When viewed via the ATI, the status display screen is updated approximately  
every 5 seconds. Use Refresh to obtain a current status of all LEDs.  
March 1997  
7510-A2-GB20-00  
4-8  
 
   
Monitoring the DSU  
System LEDs  
OK:  
ON – DSU is operational.  
OFF – DSU is performing a power-up self-test, has detected a system  
failure, or there is no power.  
ALARM:  
ON – DSU has detected an alarm condition locally or from  
Chapter 6.  
TEST:  
ON – Test in progress. Test can be initiated locally, remotely,  
or from the network. Includes power-up self-test.  
7510-A2-GB20-00  
March 1997  
4-9  
 
   
Monitoring the DSU  
Network LEDs  
DM – Data Mode:  
ON – DSU (DDS network interface) is sending or  
receiving data, or is in DMI condition  
(all 1s being received).  
OFF – DDS network interface is receiving CMI codes.  
OOS – Out of Service:  
ON – DSU is receiving out of  
service code from the remote unit.  
Table 4-2.  
OOF – Out of Frame:  
ON – DSU is detecting an out of frame  
Messages, Table 4-2.  
NS – No Signal:  
ON – DDS network interface detects  
Status Messages, Table 4-2.  
March 1997  
7510-A2-GB20-00  
4-10  
 
   
Monitoring the DSU  
Port LEDs  
TXD – Transmitted Data:  
ON  
OFF  
– Receiving all 0s from the DTE.  
– Receiving all 1s from the DTE.  
Blinking – User data is being transferred.  
RXD – Received Data:  
ON  
OFF  
– Sending all 0s to the DTE.  
– Sending all 1s to the DTE.  
Blinking – User data is being transferred.  
RTS – Request to Send:  
ON – DTE is activating a control signal to  
indicate readiness to transmit data.  
CTS – Clear to Send:  
ON – DSU is activating a control signal to  
indicate to the DTE that it can start  
sending data.  
DTR – Data Terminal Ready:  
ON – DTE is activating a control signal to  
indicate readiness for operation.  
7510-A2-GB20-00  
March 1997  
4-11  
 
   
Testing  
5
Accessing the Test Menu  
From the Test menu, you can run network tests, data port tests, and a lamp test  
for the front panel LEDs.  
To access the Test menu, follow this menu selection sequence:  
Main Menu Test  
main/test  
Device Name:  
Model: 7510  
TEST  
Network Tests  
Data Port Tests  
Lamp Test  
Abort All Tests  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
Ctrl-a to access these functions  
Exit  
The DSU supports independent tests at the physical level.  
H
H
The CSU and DSU loopbacks and 511 test pattern send/monitor are  
supported on the network interface.  
The Local Loopback and 511 test pattern send/monitor are supported on the  
DTE port.  
7510-A2-GB20-00  
March 1997  
5-1  
 
     
Testing  
Loopbacks can be started from a variety of points in the network, as shown in  
Table 5-1.  
Table 5-1. Device Messages  
Loopback Type  
Initiated By  
Notes  
Bilateral Loopback  
H User  
When enabled, running a DSU loopback  
also automatically starts a local  
Table A-3, to enable.  
H Remote unit sending  
V.54 sequence  
CSU Loopback  
H User (Network tests) When initiated by the network, CSU  
Loopback cannot be disabled by the  
H DDS Network, by  
user.  
loop current reversal  
DSU Loopback  
(Digital)  
H User  
Local Loopback  
H User  
H DTE via CT141  
Control via CT141 can be disabled.  
Network-initiated  
56 kbps DSU  
H DDS Network  
Cannot be disabled by user.  
Loopback (Non-  
latching loopback)  
Network-initiated  
64 kbps CC DSU  
Loopback  
H DDS Network  
Includes optional data scrambling and  
uses 25-second timer to detect the  
network sequence. Can be disabled by  
user.  
(Latching loopback)  
Remote Digital  
Loopback  
H Remote unit sending Same as a DSU Loopback but initiated  
V.54 sequence  
by a remote unit via V.54 sequence.  
Can be disabled locally. Refer to  
V.54 Sequences to  
remote unit  
H User  
H DTE via CT140  
Control via CT140 can be disabled.  
March 1997  
7510-A2-GB20-00  
5-2  
 
 
Testing  
Running Network Tests  
Network tests require the participation of your network service provider. To  
access the Network Tests screen, follow this menu selection sequence:  
Main Menu Test Network Tests  
main/test/network  
Device Name:  
Model: 7510  
NETWORK TESTS  
Status  
Test  
Command  
Result  
0:00:00  
CSU Loopback:  
DSU Loopback:  
Start  
Start  
Inactive  
Inactive  
0:00:00  
Send V.54 Up:  
Send  
Sending  
Send V.54 Down: Send  
Inactive  
Send 511:  
Monitor 511:  
Start  
Stop  
Inactive  
Active  
0:00:00  
125:08:48  
Errors 99999+  
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
Ctrl-a to access these functions, ESC for previous menu  
ResetMon  
MainMenu  
Exit  
Use the Command column to start or stop a test by pressing Enter. The Result  
column displays the test duration since the last device reset. When the Monitor  
511 test is active, ResetMon is available to reset the error counter to zero.  
7510-A2-GB20-00  
March 1997  
5-3  
 
     
Testing  
CSU or External Network Loopback  
CSU loopback is an external loopback that is located as closely as possible to the  
network interface.  
" Procedure  
To run a CSU loopback:  
1. Position the cursor at the Start command next to CSU Loopback on the  
Network Tests screen.  
2. Press Enter.  
3. The Start command is changed to Stop. If you want to manually stop the test,  
verify that the cursor is positioned at the Stop command.  
4. Press Enter. The duration of the test is displayed.  
DSU  
CSU  
DDS  
Network  
Port  
DTE  
Interface  
Aggregate  
DTE  
Port  
496-15144  
CSU Loopback  
March 1997  
7510-A2-GB20-00  
5-4  
 
   
Testing  
DSU or Internal Network Loopback  
DSU loopback is an internal loopback that is located as closely as possible to the  
customer interface serving the DTE.  
" Procedure  
To run a DSU loopback:  
1. Position the cursor at the Start command next to DSU Loopback on the  
Network Tests screen.  
2. Press Enter.  
3. The Start command is changed to Stop. If you want to manually stop the test,  
verify that the cursor is positioned at the Stop command.  
4. Press Enter. The duration of the test is displayed.  
DSU  
CSU  
Aggregate  
DDS  
Network  
Port  
DTE  
Interface  
DTE  
Port  
DSU Loopback  
496-15160  
Send V.54 Up/Down Sequences  
The local DSU can send an ITU-T V.54 Up or Down sequence to request the  
activation or termination of a DSU (digital) loopback of a remote unit. This is the  
same as the DSU Loopback shown above except the test is activated remotely.  
The DSU can send:  
H
H
In-band V.54 Up (activation) code to request a Remote DSU Loopback  
(V.54 Loop 2) at the remote DSU or  
In-band V.54 Down (deactivation) code to request the termination of a  
Remote DSU Loopback (V.54 Loop 2) at the remote DSU  
" Procedure  
To start or stop a remote DSU loopback:  
1. Position the cursor at the Send command next to Send V.54 Up or Send V.54  
Down on the Network Tests screen.  
2. Press Enter.  
Sending appears in the Status column followed (after 3 seconds) by  
Command Complete at the bottom of the screen.  
7510-A2-GB20-00  
March 1997  
5-5  
 
     
Testing  
511 Test Pattern for the Network  
This test sends or monitors the 511 test pattern over the network interface.  
" Procedure  
To run a Send 511 test:  
1. Position the cursor at the Start command next to Send 511 on the Network  
Tests screen.  
2. Press Enter.  
3. The Start command is changed to Stop. If you want to manually stop the test,  
verify that the cursor is positioned at the Stop command.  
4. Press Enter. The duration of the test is displayed.  
" Procedure  
To run a Monitor 511 test:  
1. Position the cursor at the Start command next to Monitor 511 on the Network  
Tests screen.  
2. If desired, use Ctrl-a to switch to the screen function key area and use the  
virtual function key r or R (ResetMon) to clear the error counter to zero. Press  
Ctrl-a to return the cursor to the Start command.  
3. Press Enter.  
4. The Start command is changed to Stop. If you want to manually stop the test,  
verify that the cursor is positioned at the Stop command.  
5. Press Enter. The duration of the test is displayed.  
March 1997  
7510-A2-GB20-00  
5-6  
 
 
Testing  
Running Data Port Tests  
Tests. To access the Data Port Tests screen, follow this menu selection  
sequence:  
Main Menu Test Data Port Tests  
main/test/port  
Device Name: Node A  
Model: 7510  
DATA PORT TESTS  
Test  
Command  
Start  
Status  
Result  
Local Loopback:  
Inactive  
000:00:00  
Send 511:  
Monitor 511:  
Start  
Stop  
Inactive  
Active  
000:00:00  
255:59:59+ – Errors 99999+  
–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––  
Ctrl–a to access these functions, ESC for previous menu  
ResetMon  
MainMenu  
Exit  
7510-A2-GB20-00  
March 1997  
5-7  
 
   
Testing  
Local Loopback  
Local Loopback loops the user data back to the DTE. This loopback is located as  
closely as possible to the User Data Port (DTE) interface.  
" Procedure  
To run a local loopback:  
1. Position the cursor at the Start command next to Local Loopback on the Data  
Port Tests screen.  
2. Press Enter.  
3. The Start command is changed to Stop. If you want to manually stop the test,  
verify that the cursor is positioned at the Stop command.  
4. Press Enter. The duration of the test is displayed.  
DSU  
CSU  
DDS  
Network  
Port  
DTE  
Interface  
DTE  
Port  
Aggregate  
496-15145  
Local Loopback  
511 Test Pattern for the DTE  
This test sends or monitors a 511 test pattern over the User Data Port interface.  
" Procedure  
To run a Send 511 test:  
1. Position the cursor at the Start command next to Send 511 on the Data Port  
Tests screen.  
2. Press Enter.  
3. The Start command is changed to Stop. If you want to manually stop the test,  
verify that the cursor is positioned at the Stop command.  
4. Press Enter. The duration of the test is displayed.  
March 1997  
7510-A2-GB20-00  
5-8  
 
   
Testing  
" Procedure  
To run a Monitor 511 test:  
1. Position the cursor at the Start command next to Monitor 511 on the Data  
Port Tests screen.  
2. If desired, use Ctrl-a to switch to the screen function key area and use the  
virtual function key r or R (ResetMon) to clear the error counter to zero. Press  
Ctrl-a to return the cursor to the Start command.  
3. Press Enter.  
4. The Start command is changed to Stop. If you want to manually stop the test,  
verify that the cursor is positioned at the Stop command.  
5. Press Enter. The duration of the test is displayed.  
The 511 monitor expects the external equipment to provide the clock for the  
511 pattern on the interchange circuit CT113 (TT), for timing the incoming pattern.  
Running the Lamp Test  
The DSU supports a Lamp test from the Test menu to determine whether all  
LEDs light up.  
During the Lamp test, all LEDs blink simultaneously once per second. When you  
stop the Lamp test, the LEDs are restored to their normal condition.  
To access the Data Port Tests screen, follow this menu selection sequence:  
Main Menu Test Lamp Test  
" Procedure  
To run a Lamp test:  
1. Position the cursor at the Start command next to Lamp Test on the Lamp Test  
screen.  
2. Press Enter.  
3. The Start command is changed to Stop. When you want to stop the test,  
verify that the cursor is positioned at the Stop command.  
4. Press Enter.  
7510-A2-GB20-00  
March 1997  
5-9  
 
   
Testing  
Ending an Active Test  
A test initiated by the user can be ended by the user.  
H
A Test Timeout option is available to automatically terminate a user-initiated  
Loopback or Pattern test after it has been running a specified period of time.  
Test Timeout does not pertain to tests commanded by the:  
— Network, such as the network-initiated CSU and DSU Loopbacks.  
— DTE, such as the DTE-initiated Local Loopback.  
H
H
On each test screen is a command column. Pressing Return when the cursor  
is on the Stop command stops the test.  
Use the Abort All Tests selection from the Test menu to stop all tests running  
on all interfaces, with the exception of network or DTE-initiated loopbacks.  
Command Complete appears when all tests on all interfaces have been  
terminated.  
March 1997  
7510-A2-GB20-00  
5-10  
 
   
Messages and Troubleshooting  
6
Messages and Troubleshooting  
There are many messages available to assess the status of the device and  
contribute to problem resolutions. Refer to the following sections:  
H
H
Responding to Device Messages  
The Device Messages in Table 6-1, listed in alphabetical order, may appear in the  
messages area at the bottom of the ATI screens.  
Table 6-1. Device Messages (1 of 2)  
Device Message  
What Message Indicates  
What To Do  
Command Complete  
Action requested has  
successfully completed.  
No action needed.  
Invalid Character x  
A nonprintable ASCII  
character has been  
entered.  
Reenter information using valid  
characters.  
Invalid – Network  
Network-initiated loopback  
No action needed.  
Initiated CSU (or DSU) was in progress when  
Loopback Active  
another selection was  
made.  
Invalid – [Test]  
Already Active  
[Test] can be a CSU, DSU,  
or DTE Local Loopback, or  
a Send 511 or Monitor 511.  
The [test] was already in  
progress when another  
selection was made.  
H Allow test to continue.  
H Select another test.  
H Stop the test.  
7510-A2-GB20-00  
March 1997  
6-1  
 
       
Messages and Troubleshooting  
Table 6-1. Device Messages (2 of 2)  
Device Message  
What Message Indicates  
What To Do  
Invalid Test  
Combination  
A loopback or 511 pattern  
test was in progress when  
Start was selected to start  
another test, or was active  
on the same or another  
interface when Start was  
selected.  
H Wait until other test ends and  
message clears.  
H Abort all tests from the Test  
menu screen.  
H Stop the test from the same  
screen the test was started  
from.  
Please Wait  
Test Active  
Command takes longer  
than 5 seconds.  
Wait until message clears.  
A test is running and no  
higher priority health and  
status messages exist.  
H Contact service provider if test  
initiated by the network.  
H Wait until the other test ends  
and message clears.  
H Cancel all tests from the Test  
screen.  
H Stop the test from the same  
screen the test was started  
from.  
March 1997  
7510-A2-GB20-00  
6-2  
 
 
Messages and Troubleshooting  
Troubleshooting  
This DSU is designed to provide you with many years of trouble-free service. If a  
problem occurs, however, refer to Table 6-2 for possible solutions.  
Table 6-2. Troubleshooting (1 of 2)  
Symptom  
Possible Cause  
Solutions  
Alarm LED is on.  
One of several alarm  
conditions exists. Health  
and Status displays the  
alarm condition.  
recommended action.  
Cannot access the  
DSU via the ATI.  
The terminal is not set up  
for the correct rate or data  
format, or the DSU is  
configured so it prevents  
access.  
1. Check the cable and  
connections.  
2. Set up your terminal or PC  
emulation as shown in  
in Chapter 2.  
3. Power the DSU on and off and  
try again.  
Device Fail appears The DSU detects an  
H Power the DSU off and on and  
on the System and  
Test Status screen  
under Self-Test  
results.  
internal hardware failure.  
try again.  
H Contact your service  
representative.  
An LED is not lit.  
LED is burned out.  
Run the Lamp test. If the LED in  
question does not flash with the  
other LEDs, then contact your  
service representative.  
No power, or the  
LEDs are not lit.  
The power cord is not  
Check that the power cord is  
securely attached at both ends.  
securely plugged into the  
wall receptacle and into the  
rear panel connection.  
The wall receptacle has no  
power.  
H Check the wall receptacle power  
by plugging in some equipment  
that is known to be working.  
H Check the circuit breaker.  
H Verify that your site is not on an  
energy management program.  
Power supply has failed.  
Replace power supply.  
7510-A2-GB20-00  
March 1997  
6-3  
 
   
Messages and Troubleshooting  
Table 6-2. Troubleshooting (2 of 2)  
Symptom Possible Cause  
Solutions  
Not receiving data;  
DSU is not  
H DDS line rate/speed has 1. Verify that your subscriber loop is  
changed.  
running at 56 or 64 CC kbps.  
responding.  
H Excessive BPVs causing  
DSU to become stuck in  
Autobaud mode.  
2. If getting Excessive BPVs, verify  
that you do not have a bad cable.  
If the cable is good, contact the  
network provider.  
H Excessive Loop Loss  
causing DSU to become  
stuck in Autobaud mode.  
3. If getting excessive Loop Loss  
(dB) indications, install a higher  
quality cable. Refer to Table D-2  
in Appendix D, Model 7510  
Distances.  
4. If the DDS Line Rate (Kbps) field  
shows Autobaud, the DSU may  
be stuck in Autobaud mode.  
Configure Line Rate (Kbps) for  
56 or 64 kbps.  
5. Run Loopback tests. Refer to  
Chapter 5.  
Power-Up Self-Test The DSU has detected an  
H Reset the DSU and try again.  
fails. Only Alarm  
LED is on after  
power-up.  
internal hardware failure.  
H Contact your service  
representative.  
Resetting the DSU  
The DSU can be reset locally or remotely.  
To reset the DSU, follow this menu selection sequence:  
Main Menu Control Reset Device  
The DSU reinitializes itself, performing a Device Self-Test. Refer to Self-Test  
Displaying DSU Identity Information  
To display the DSU’s system name, location, contact, serial number, model  
number, and software and hardware revision numbers, follow this menu selection  
sequence:  
Main Menu Status Identity  
March 1997  
7510-A2-GB20-00  
6-4  
 
     
Configuration Option Tables  
A
Overview  
The tables in this appendix summarize the configuration options accessed when  
you select Configuration on the Main Menu. The configuration options are  
arranged into groups based upon functionality.  
Select . . .  
To Access the . . .  
To Configure the . . .  
System  
General system  
options  
Network  
DDS network interface  
User data on DTE port  
ATI  
Data Port  
Terminal Port  
NOTE:  
MAIN MENU  
Status  
Test  
Configuration  
Control  
Configuration  
Edit/Display  
System  
Load  
Configuration  
From ...  
Network  
Data Port  
Terminal Port  
497-15239  
7510-A2-GB20-00  
March 1997  
A-1  
 
     
Configuration Option Tables  
System Options Menu  
For System Options, refer to Table A-1. To access the System Options screen,  
follow this menu selection sequence:  
Main Menu Configuration (Load Configuration From) →  
Configuration Edit/Display System  
Table A-1. System Options (1 of 2)  
Operating Mode  
Possible Settings: DDS, LADS  
Default Setting: DDS  
The unit’s operating mode depends upon the DSU’s application.  
DDS – Standard DDS network operation. The operating rate is either 56 kbps or  
64 kbps CC.  
LADS – The Local Area Data Set operating mode requires that the local and remote  
units are connected directly to each other. This is a point-to-point application; also  
known as LDM.  
DDS Line Rate (Kbps)  
Possible Settings: 56, 64CC, Autobaud  
Default Setting: Autobaud  
The unit starts up with Autobaud. When the DDS line rate obtained from the service  
provider is detected, Autobaud is replaced with the actual rate.  
H DDS Line Rate (Kbps) option appears when Operating Mode is set to DDS.  
NOTE: Setting the actual data rate will result in minimum power-up time.  
Configuring the actual data rate is recommended after initial installation.  
56 – 56 kbps line rate.  
64CC – 64 kbps Clear Channel on a 72 kbps circuit.  
Autobaud – This setting is automatically changed to the actual operating line rate of  
56 kbps or 64CC as soon as the signal is detected.  
LADS Timing  
Possible Settings: Internal, External, Receive  
Default Setting: Receive  
Determines the timing source for the unit.  
H LADS Timing option appears when Operating Mode is set to LADS.  
Internal – Timing derived from the unit’s local clock. Use this setting for the LADS  
primary timing unit that establishes the timing for both point-to-point units.  
External – Timing is derived from the external clock provided by the DTE connected to  
the V.35 interface on circuit CT113 (pins U, W).  
Receive – Timing is derived from the line receive signal unless the unit is running  
diagnostic tests. During the tests, the timing source is the internal clock. This setting  
should be used for a LADS secondary timing unit.  
March 1997  
7510-A2-GB20-00  
A-2  
 
       
Configuration Option Tables  
Table A-1. System Options (2 of 2)  
LADS Line Rate (Kbps)  
Possible Settings: 56, 64  
Default Setting: 64  
Line operating rate for LADS operation.  
H LADS Line Rate (Kbps) option appears when Operating Mode is set to LADS.  
56 – 56 kbps line rate. Provides increased distance for the LADS applications.  
64 – 64 kbps line rate.  
Test Timeout  
Possible Settings: Enable, Disable  
Default Setting: Enable  
Allows user-initiated tests to end automatically. Recommend enabling when the unit is  
managed remotely through the IMC to avoid the requirement to terminate the test  
manually.  
Enable – User-initiated loopback and pattern tests end when test duration is reached.  
Disable Tests must be terminated manually from the Network Tests screen. Refer to  
Running Network Tests in Chapter 5.  
NOTE: Tests commanded by the DTE or network-initiated tests are not affected by  
this test timeout.  
Test Duration (min)  
Possible Settings: 1–120  
Default Setting: 10  
Number of minutes for a test to be active before automatically ending.  
H Test Duration (min) option appears when Test Timeout is enabled.  
1 to 120 – Amount of time in minutes for a user-initiated test to run before terminating.  
7510-A2-GB20-00  
March 1997  
A-3  
 
Configuration Option Tables  
Network Interface Options Menu  
For Network Interface Options, refer to Table A-2. To access the Network  
Interface Options screen, follow this menu selection sequence:  
Main Menu Configuration (Load Configuration From) →  
Configuration Edit/Display Network  
Table A-2. Network Interface Options  
Network-initiated DSU Loopback (64K CC)  
Possible Settings: Enable, Disable  
Default Setting: Enable  
Indicates whether the access unit responds to a DSU latching loopback sequence sent  
by the network as specified by TR62310.  
is set to DDS in Table A-1.  
Enable – Responds to network-initiated commands to start and stop a latching DSU  
loopback.  
Disable – DSU will not respond to a DSU loopback initiated by the network.  
Data Scrambling (64K CC)  
Possible Settings: Enable, Disable  
Default Setting: Disable  
Data scrambling is used to suppress the possible simulation of network-initiated DSU  
latching loopback commands by application data.  
Table A-1.  
Enable – Enables data scrambling. The local and remote units must be set the same.  
Disable – No data scrambling.  
V.54 Initiated DSU Loopback  
Possible Settings: Enable, Disable  
Default Setting: Disable  
When enabled, user data is looped back to the network when a V.54 Loop Up sequence  
is received. The DSU loopback ends when a V.54 Loop Down sequence is detected.  
Enable – DSU loopback can be initiated or terminated by a remote unit sending in-band  
V.54 Loop 2 Up or Down sequences.  
Disable V.54 Loop 2 sequences are ignored.  
March 1997  
7510-A2-GB20-00  
A-4  
 
       
Configuration Option Tables  
Data Port Options Menu  
For Data Port Options, refer to Table A-3. To access the Data Port Options  
screen, follow this menu selection sequence:  
Main Menu Configuration (Load Configuration From) →  
Configuration Edit/Display Data Port  
Table A-3. Data Port Options (1 of 3)  
Invert Transmit Clock  
Possible Settings: Enable, Disable  
Default Setting: Disable  
The DSU clock provided on Interchange Circuit CT114, Transmit Signal Element Timing  
DCE source (TXC), is phase inverted with respect to Interchange Circuit CT103,  
Transmitted Data (TXD). Recommended when data errors are occurring due to long  
cable lengths.  
Enable – The DSU-supplied clock is phase inverted with respect to the transmitted data  
TXD.  
Disable – The clock supplied by the DSU on TXC is normal (i.e., not inverted).  
Port (DTE) Initiated Loopbacks  
Possible Settings: Disable, Local, Remote, Both  
Default Setting: Disable  
Specifies whether the DTE can initiate and terminate local and/or remote loopbacks.  
The DTE loopback control is done through the Interchange Circuits specified by the  
V.54 standard.  
Disable – No local or remote loopbacks can be initiated by the DTE.  
Local – A local loopback can be controlled by the DTE, via the Interchange Circuit LL  
(CT141), as specified by V.54. The DTE port remains in loopback as along as LL  
remains on. Aborting the loopback from the ATI has no effect.  
Remote – A remote digital loopback can be controlled by the DTE, via Interchange  
Circuit RL (CT140), as specified by V.54. The remote equipment must be able to detect  
the in-band V.54 loopback sequence.  
Both – Both the local and remote loopbacks can be controlled by the DTE.  
Bilateral Loopback  
Possible Settings: Enable, Disable  
Default Setting: Disable  
When a DSU loopback is initiated, a local DTE loopback is also automatically initiated.  
A Bilateral Loopback can be started by the ATI/NMS or by detection of a V.54 Loop 2 Up  
sequence.  
Enable – When Bilateral Loopback is enabled, running a DSU loopback also  
automatically starts a local loopback. The local loopback ends when the DSU loopback  
terminates.  
Disable – Running a DSU loopback does not start a local loopback.  
7510-A2-GB20-00  
March 1997  
A-5  
 
   
Configuration Option Tables  
Table A-3. Data Port Options (2 of 3)  
Carrier Control by RTS  
Possible Settings: Constant, Switched  
Default Setting: Constant  
Simulates Constant or Switched Carrier operation.  
Constant – The internal RTS is forced on and the DSU is in a constant Data Mode on  
the transmit line. The external RTS lead is ignored. The actual signal on the line is either  
all ones (DMI) or DTE transmitted data.  
Switched – RTS is monitored and CMI codes are transmitted when RTS is off.  
CTS Control  
Possible Settings: Standard, Follow RTS, Forced On, Circuit Assurance  
Default Setting: Standard  
Specifies the operation of the Interchange Circuit CT106, Clear to Send (CTS), which is  
an output from the DSU.  
Standard – CTS follows the internal RTS with a fixed delay, except that CTS will be off  
when a network interface related alarm is detected or a test is active. The active test  
may be initiated locally, remotely, or by the network.  
Follow RTS – CTS follows the external RTS lead without delay, regardless of alarms  
and tests.  
Forced On – CTS is always forced on after the unit is powered up with a successful  
self-test.  
Circuit Assurance – With circuit assurance, CTS operates the same as the Standard  
option, except that CTS will also be deasserted when CMI codes are being received.  
RLSD Control  
Possible Settings: Standard, Forced On  
Default Setting: Standard  
Specifies the operation of the Interchange Circuit CT109, Received Line Signal Detector  
(RLSD or CD), which is an output from the DSU.  
Standard – RLSD is asserted when Data Mode is on the receive line. RLSD deasserts  
when a DDS facility alarm is detected or the DSU is receiving CMI codes.  
Forced On – RLSD is forced on after the unit is powered up with a successful self-test.  
DSR Control  
Possible Settings: Standard, Forced On, On During Test  
Default Setting: Standard  
Specifies the operation of the Interchange Circuit CT107, Data Set Ready (DSR), which  
is an output from the DSU.  
Standard – DSR is always asserted, except when a DDS facility alarm is reported or  
the DSU is in Test mode.  
Forced On – DSR is forced on after the unit is powered up with a successful self-test.  
On During Test – DSU operates the same as the Standard option, except that DSR  
remains asserted when the DSU is in Test mode to allow the DTE to send test patterns.  
March 1997  
7510-A2-GB20-00  
A-6  
 
Configuration Option Tables  
Table A-3. Data Port Options (3 of 3)  
Monitor DTR  
Possible Settings: Enable, Disable  
Default Setting: Enable  
Indicates to the DSU whether to monitor the Interchange Circuit CT108, Data Terminal  
Ready (DTR), from the DTE.  
Enable – The DSU monitors the state of DTR on the DTE port and displays it on the  
System and Test Status screen.  
Disable – DTR is not monitored by the DSU. Use when a DTE does not provide the  
DTR lead at the interface.  
Terminal Port Options  
For Terminal Port options, refer to Table A-4. To access the Terminal Port Options  
screen, follow this menu selection sequence:  
Main Menu Configuration (Load Configuration From) →  
Configuration Edit/Display Terminal Port  
Table A-4. Terminal Port Options (1 of 2)  
Monitor DTR  
Possible Settings: Enable, Disable  
Default Setting: Enable  
Specifies monitoring of the Data Terminal Ready (DTR) control lead.  
Enable – Standard operation of the DTR control lead.  
Disable – DTR is ignored. Some external device connections may require this setting.  
Inactivity Timeout  
Possible Settings: Enable, Disable  
Default Setting: Disable  
Provides automatic logoff of an ATI session through the Terminal Port. When the  
session is closed, User Interface Idle appears on the screen and the unit toggles the  
Terminal port DSR lead.  
Enable – The ATI session terminates automatically after the Disconnect Time set in the  
next option. When the session was occurring over an external modem connected to the  
Terminal port, the modem will interpret the DSR toggle as DTR being dropped and  
disconnect.  
Disable – An ATI session through the Terminal port will remain active indefinitely.  
7510-A2-GB20-00  
March 1997  
A-7  
 
     
Configuration Option Tables  
Table A-4. Terminal Port Options (2 of 2)  
Disconnect Time(minutes)  
Possible Settings: range 1 – 60  
Default Setting: 5  
Number of minutes of inactivity before the ATI session terminates automatically.  
Timeout is based on no keyboard activity.  
H Disconnect Time(minutes) option appears when Inactivity Timeout is enabled.  
1 to 60 – The ATI user session is closed after the selected number of minutes.  
March 1997  
7510-A2-GB20-00  
A-8  
 
Worksheets  
B
Overview  
The worksheets in this appendix summarize the configuration options accessed  
when you select Configuration on the Main Menu. The possible menu selections  
are displayed with the default settings and the possible settings.  
Configuration Worksheets  
System  
Configuration Option  
Operating Mode  
DDS Line Rate (Kbps)  
LADS Timing  
Settings  
Default in [Bold]  
[DDS], LADS  
56, 64CC, [Autobaud]  
Internal, External, [Receive]  
56, [64]  
LADS Line Rate (Kbps)  
Test Timeout  
[Enable], Disable  
1–120, [10]  
Test Duration (min)  
7510-A2-GB20-00  
March 1997  
B-1  
 
       
Worksheets  
Network Interface  
Configuration Option  
Settings  
Default in [Bold]  
Network-initiated DSU Loopback (64K CC) [Enable], Disable  
Data Scrambling (64K CC)  
V.54 Initiated DSU Loopback  
Enable, [Disable]  
Enable, [Disable]  
Data Port  
Configuration Option  
Invert Transmit Clock  
Port (DTE) Initiated Loopbacks  
Bilateral Loopback  
Carrier Control by RTS  
CTS Control  
Settings  
Default in [Bold]  
Enable, [Disable]  
[Disable], Local, Remote, Both  
Enable, [Disable]  
[Constant], Switched  
[Standard], Follow RTS, Forced On,  
Circuit Assurance  
RLSD Control  
DSR Control  
Monitor DTR  
[Standard], Forced On  
[Standard], Forced On, On During Test  
[Enable], Disable  
Terminal Port  
Configuration Option  
Monitor DTR  
Settings  
Default in [Bold]  
[Enable], Disable  
Enable, [Disable]  
range 1 – 60 [5]  
Inactivity Timeout  
Disconnect Time(minutes)  
March 1997  
7510-A2-GB20-00  
B-2  
 
Cables and Pin Assignments  
C
Overview  
The following sections provide pin assignments for the:  
H
H
H
H
H
7510-A2-GB20-00  
March 1997  
C-1  
 
     
Cables and Pin Assignments  
Terminal Port EIA-232 Connector  
The Terminal port connects to a PC or VT100-compatible terminal.  
Signal  
Direction  
Pin #  
Transmit Data (TXD)  
Received Data (RXD)  
Request to Send (RTS)  
Clear to Send (CTS)  
Data Set Ready (DSR)  
Signal Ground (SG)  
Carrier Detect (CD)  
To DSU (In)  
From DSU (Out)  
To DSU (In)  
From DSU (Out)  
From DSU (Out)  
2
3
4
5
6
7
From DSU (Out)  
8
Data Terminal Ready (DTR) To DSU (In)  
20  
March 1997  
7510-A2-GB20-00  
C-2  
 
 
Cables and Pin Assignments  
V.35 User Data Port Connector  
The following table provides the pin assignments for the 34-position  
V.35 connector to the User Data terminal equipment.  
34-Pin  
Socket  
Connector  
ITU  
Signal  
Direction  
CT#  
102  
105  
106  
107  
109  
Signal Ground/Common  
Request to Send (RTS)  
Clear to Send (CTS)  
Data Set Ready (DSR)  
B
C
D
E
F
To DSU (In)  
From DSU (Out)  
From DSU (Out)  
From DSU (Out)  
Received Line Signal Detector  
(RLSD or LSD)  
Data Terminal Ready (DTR)  
Remote Loopback (RL)  
Local Loopback (LL)  
108/1, /2 To DSU (In)  
H
N
L
140  
141  
103  
To DSU (In)  
To DSU (In)  
To DSU (In)  
Transmitted Data (TXD)  
P (A)  
S (B)  
Received Data (RXD)  
104  
113  
115  
114  
142  
From DSU (Out)  
To DSU (In)  
R (A)  
T (B)  
Transmitter Signal Element Timing –  
DTE Source (XTXC or TT)  
U (A)  
W (B)  
Receiver Signal Element Timing –  
DCE Source (RXC)  
From DSU (Out)  
From DSU (Out)  
From DSU (Out)  
V (A)  
X (B)  
Transmitter Signal Element Timing –  
DCE Source (TXC)  
Y (A)  
AA (B)  
Test Mode Indicator (TM)  
NN  
7510-A2-GB20-00  
March 1997  
C-3  
 
   
Cables and Pin Assignments  
Standard EIA-232-D Crossover Cable  
A standard crossover cable can be used to connect the Terminal port to an  
external modem.  
Pin 14  
Pin 1  
Pin 1  
P1  
Plug  
P2  
Plug  
Pin 14  
Pin 25  
Pin 13  
Pin 25  
Pin 13  
P1  
Pin  
Pin  
P2  
Chassis Ground  
Chassis Ground  
1
2
1
TXD  
RXD  
RTS  
TXD  
RXD  
RTS  
2
3
3
4
4
5
5
DSR  
DSR  
Signal Ground  
CD (RLSD)  
6
6
Signal Ground  
CD (RLSD)  
7
7
8
8
9
9
10  
11  
12  
13  
14  
15  
16  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
RXC  
DTR  
RXC 17  
18  
19  
DTR 20  
21  
22  
23  
XTXC  
XTXC 24  
25  
97-15180-01  
March 1997  
7510-A2-GB20-00  
C-4  
 
   
Cables and Pin Assignments  
LAN Adapter Converter and Cable  
The following figure shows the:  
H
H
Pin assignments for the DB25 plug to modular jack converter between the  
Management port and the 8-conductor LAN Adapter cable and  
Pin assignments for the custom 8-conductor cable (with modular plugs on  
both ends) between the converter and the LAN Adapter.  
Plug-to-Modular  
Jack Converter  
Cable  
Management  
8-Position  
Plug to  
Plug to  
Port (DB25 Plug)  
Modular Jack  
Modular Jack  
LAN Adapter  
Tx Clock 15  
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
Unused  
Rx Data  
3
7
2
DTR  
Signal Ground  
Tx Data  
Tx Data  
Signal Ground  
Rx Data  
CTS  
DTR 20  
CD  
8
4
RTS  
Frame Ground  
Unused  
Rx Clock 17  
496-15179  
Modular RJ48S DDS Network Interface Cable  
Network access is via a 14-foot modular cable with an RJ48S keyed plug  
connector on each end.  
RJ48S DDS Network  
Interface Cable Functions  
Circuit Pin #  
Transmitted data to the local loop  
Transmitted data to the local loop  
Received data from the local loop  
Received data from the local loop  
R
T
1
2
7
8
T1  
R1  
7510-A2-GB20-00  
March 1997  
C-5  
 
     
Technical Specifications  
D
Table D-1. Model 7510 DSU Technical Specifications (1 of 2)  
Item  
Specifications  
Housing  
Height (including feet)  
Height (without feet)  
Width  
2.13 inches (54.1 mm)  
1.99 inches (50.6 mm)  
9.10 inches (231.2 mm)  
6.20 inches (157.5 mm)  
Depth (case)  
Depth (case and connectors) 6.51 inches (165.3 mm)  
Weight  
Power  
1.3 pounds (0.6 kg)  
Normal service voltage  
range  
Input: 120 Vac +12 Vac, 60 Hz +3 Hz  
4.9 watts (max.) at 120 Vac  
Approvals  
FCC Part 15  
FCC Part 68  
Safety Certifications  
Emissions  
Class A digital device  
Refer to the equipment’s label for Registration Number.  
Refer to the equipment’s label for approvals on product.  
Class A digital apparatus  
Interface and Connectors  
25-pin D-subminiature  
connector  
EIA-232/ ITU V.24 (ISO 2110) for Terminal Port  
ITU V.35 (ISO 2593) for DTE Port  
34-pin MS34 connector  
Physical Environment  
Operating Temperature  
Storage Temperature  
Relative Humidity  
32° to 122° F (0° to 50° C)  
4° to 158° F (–20° to 70° C)  
5%95% (noncondensing)  
Shock and Vibration  
Withstands normal shipping and handling  
Heat Dissipation  
11.6 Btu/hr. (max.) at 120 Vac  
7510-A2-GB20-00  
March 1997  
D-1  
 
   
Technical Specifications  
Table D-1. Model 7510 DSU Technical Specifications (2 of 2)  
Item  
Specifications  
Network Interface  
Data rates  
56 kbps and 64 kbps clear channel (CC)  
56 kbps and 64 kbps  
LADS data rates  
Services supported  
4-wire service  
Network Compatibility  
ANSI T1.410-1992 and  
AT&T Technical Reference  
62310-1993  
56 and 64 kbps meeting desired loop loss  
34-pin V.35 connector  
DTE Data Port Interface  
Table D-2. Model 7510 DSU LADS Connection Distances  
Wire Diameter (AWG)  
19 Gauge  
(.0359I or  
.9122 mm)  
22 Gauge  
(.0253I or  
.643 mm)  
24 Gauge  
(.0201I or  
.511 mm)  
26 Gauge  
(.0159I or  
.404 mm)  
Data Rate  
(kbps)  
56  
10.84 mi  
6.4 mi  
4.50 mi  
3.34 mi  
(17.45 km)  
(10.3 km)  
(7.24 km)  
(5.37 km)  
64  
10.69 mi  
6.06 mi  
4.47 mi  
3.20 mi  
(17.2 km)  
(9.76 km)  
(7.2 km)  
(5.15 km)  
March 1997  
7510-A2-GB20-00  
D-2  
 
   
Glossary  
aggregate  
ASCII  
A single bit stream that combines two or more bit streams.  
American Standard Code for Information Interchange. A 7-bit code that establishes  
compatibility between data services. ASCII is the standard for data transmission over  
telephone lines.  
ASCII Terminal or  
Printer  
Devices that can be attached, either locally or remotely, to display or print the DSU’s alarm  
messages.  
asynchronous  
A data transmission that is synchronized by a transmission start bit at the beginning of  
a character (five to eight bits) and one or more stop bits at the end.  
AT Command Set  
Attention Command Set. A group of commands, issued from an asynchronous DTE, that  
allows control of the modem while in Command mode. All commands must begin with the  
characters AT and end with a carriage return.  
ATI  
Asynchronous terminal interface. This feature allows a device to be controlled from an  
async (asynchronous) terminal like an ASCII (VT100-compatible) terminal.  
autobaud mode  
An operational mode in which the DSU forces automatic setting of the DDS line rate/speed  
(56 or 64 kbps) as soon as a valid DDS network signal is detected.  
AUX port  
BPV  
The auxiliary communications port on a router.  
Bipolar Violation. A modified bipolar signaling method in which a control code is inserted.  
Circuit Card Assembly. A printed circuit board to which separate components are attached.  
Consultative Committee on International Telegraphy and Telephony. See ITU.  
CCA  
CCITT  
CD  
Carrier Detect. A signal indicating that energy exists on the transmission circuit.  
Associated with Pin 8 on an EIA-232 interface.  
channel  
CMI  
An independent data path.  
Control Mode Idle. A control signal sent over the DDS line to indicate that no data is being  
sent.  
COM port  
Communications port. A computer’s serial communications port used to transmit to and  
receive data from a DCE. The DCE connects directly to this port.  
configuration option  
CPE  
Device software that sets specific operating parameters for the DSU.  
Customer Premises Equipment. Terminating equipment supplied by either the customer or  
some other supplier that is connected to the telecommunications network (e.g., DSUs,  
terminals, phones, routers, modems).  
CSU  
CTS  
DCE  
Channel Service Unit. The function of the DSU that protects the T1 line from damage and  
regenerates the T1 signal.  
Clear to Send. An EIA-lead standard for V.24 circuit CT 106; an output signal  
(DCE-to-DTE).  
Data Communications Equipment. The equipment that provides the functions required to  
establish, maintain, and end a connection. It also provides the signal conversion required  
for communication between the DTE and the network.  
DDS  
Digital Data Service. Provides digital communication circuits.  
7510-A2-GB20-00  
March 1997  
GL-1  
 
 
Glossary  
DMI  
DSR  
DSU  
DTE  
DTR  
EIA  
Data Mode Idle. Refers to a sequence of ones transmitted or received on the DDS  
network.  
Data Set Ready. An EIA-lead standard for V.24 circuit CT 107; an output signal  
(DCE-to-DTE).  
Data Service Unit. Data communications equipment that provides an interface between the  
DTE and the digital network.  
Data Terminal Equipment. The equipment, such as computers and printers, that provides  
or creates data.  
Data Terminal Ready. An EIA-lead standard for V.24 circuit CT 108; an input signal  
(DTE-to-DCE).  
Electronic Industries Association. This organization provides standards for the data  
communications industry to ensure uniformity of interface between DTEs and DCEs.  
EIA-232  
The EIA’s standards defining the 25-pin interface between the DTE and DCE.  
excessive BPV  
An excessive bipolar violation condition results when at least one invalid bipolar violation  
has occurred every 20 milliseconds for 2 seconds.  
factory defaults  
FCC  
A predetermined set of configuration options for general operation.  
Federal Communications Commission. Board of Commissioners that regulates all U.S.  
interstate, intrastate, and foreign electrical communication systems that originate from the  
United States.  
frame relay  
A switching interface that is designed to get frames from one part of the network to another  
as quickly as possible.  
full-duplex  
HDLC  
The capability to transmit in two directions simultaneously.  
High-Level Data Link Control. A communications protocol defined by the International  
Standards Organization (ISO).  
interface  
ITU  
A shared boundary between functional units.  
International Telecommunication Union, formerly known as CCITT. An advisory committee  
established by the United Nations to recommend communications standards and policies.  
LADS  
Local Area Data Set is used to provide a point-to-point link between two devices (also  
called LDM – limited distance modem).  
LAN  
Local Area Network. A network designed to connect devices over short distances, like  
within a building.  
latching loopback  
LED  
A latching loopback can only be initiated or terminated by the 64 kbps clear channel  
network service provider.  
Light Emitting Diode. A status indicator that responds to the presence of a certain  
conditions.  
link layer protocol  
LL  
The protocol that regulates the communication between two network nodes.  
Local Loopback. An EIA-lead standard for V.24 circuit CT 141; an input signal  
(DTE-to-DCE).  
loopback  
LSD  
Used to test various portions of a data link in order to isolate an equipment or data line  
problem. A diagnostic procedure that sends a test message back to its origination point.  
Line Signal Detect. An EIA-lead standard for V.24 circuit CT 109; an output signal  
(DCE-to-DTE).  
March 1997  
7510-A2-GB20-00  
GL-2  
 
Glossary  
multiplexing  
node  
A method for interleaving several access channels onto a single circuit for transmission  
over the network.  
A connection or switching point on the network.  
non-latching  
loopback  
A non-latching loopback can only be initiated or terminated by the 56 kbps network service  
provider.  
NS  
No Signal. A network-reported condition.  
OOF  
Out Of Frame. An error condition in which frame synchronization bits are in error. A  
network-reported condition.  
OOS  
Out of Service. A digital network trouble signal.  
Packet Assembler/Disassembler.  
PAD  
point-to-point circuit  
protocol  
A data network circuit with one control and one tributary device.  
The rules that govern how devices exchange information on a network. It covers timing,  
format, error control, and flow control during data transmission.  
PSTN  
Public Switched Telephone Network. A network shared among many users who can use  
telephones to establish connections between two points.  
reset  
A reinitialization of the device that occurs at power-up or in response to a reset command.  
Routing Information Protocol. Specifies the routing protocol used between DSUs.  
Receive Line Signal Detect. See CD.  
RIP  
RLSD  
router  
A device that makes decisions about the paths network traffic should take and forwards  
that traffic to its destination. A router helps achieve interoperability and connectivity  
between different vendor’s equipment, regardless of protocols used.  
RS-232  
RTS  
An EIA standard for the 25-pin DCE/DTE interface. Same as EIA-232.  
Request to Send. An EIA-lead standard for V.24 circuit CT 105; an input signal  
(DTE-to-DCE).  
RXC  
RXD  
Received Clock. An EIA-lead standard for V.24 circuit CT 115; an output signal  
(DCE-to-DTE).  
Received Data. An EIA-lead standard for V.24 circuit CT 104; an output signal  
(DCE-to-DTE).  
SDLC  
Synchronous Data Link Control. A standard data link protocol.  
synchronous  
Data transmission that is synchronized by timing signals. Characters are sent at a fixed  
rate.  
TDM  
Time Division Multiplexer. A device that enables the simultaneous transmission of multiple  
independent data streams into a single high-speed data stream.  
TM  
Test Mode. An EIA-lead standard for V.24 circuit CT 142; an output signal (DCE-to-DTE).  
TXC  
Transmit Clock. An EIA-lead standard for V.24 circuit CT 114; an output signal  
(DCE-to-DTE).  
TXD  
Transmit Data. An EIA-lead standard for V.24 circuit CT 103; an input signal  
(DTE-to-DCE).  
V.35  
ITU-T standard for a high-speed, 34-pin, DCE/DTE interface.  
WAN  
Wide Area Network. A network that operates over long distances and spans a relatively  
large geographic area (e.g., a country).  
7510-A2-GB20-00  
March 1997  
GL-3  
 

MTD Log Splitter 249 645A User Manual
MTD Yard Vacuum 24665C User Manual
NEC Server 456 01721 000 User Manual
NetComm Network Router NP725 User Manual
Nextar MP3 Player MA177 User Manual
Nokia Cell Phone 211S User Manual
Omega Thermometer TC 08 User Manual
One for All Universal Remote Univeral Remote User Manual
Palsonic Flat Panel Television TFTV1720D User Manual
Panasonic Vacuum Cleaner MC CL310 User Manual