Setting Switch Options SW2–1 Through SW2–8
Loop-back
Loop-back is the maintenance routine used to verify the receive function (local or remote) and to isolate system
problems. The network can remotely activate the loop-back feature using ESF (ANSI T1.403) facility data link.
You can manually make three different types of loop-back requests depending on the option you select using DIP
switches SW2–7 and SW2–8. These are: local, remote, and payload loop-back.
•
Local loop-back returns transmitted signals back to the DXP.
•
Remote loop-back returns received signals back to the network. The ANSI T1.403 specification refers to this
feature as line loop-back.
•
Pay-load loop-back is similar to remote loop-back except the system reestablishes framing bit.
Customer Service Unit (CSU) Identification Bit
You can set the message-oriented (C/R) bit transmitted over the ESF data link by DIP switch SW2–2 to be a zero
(0) bit or a one (1) bit. The C/R bit is used to identify the T1 signal origin as being either from customer premise
equipment (CPE) or carrier equipment such as a CSU.
Set C/R to be a zero (0) bit for customer premise equipment (CPE) or when using an external CSU (default).
Set C/R to be a one (1) bit if the network requires the T1 internal CSU to be classified as carrier equipment.
Cyclic Redundancy Check (CRC-6)
This is a method for checking the accuracy of data transmissions when using the ESF format. This method uses a
polynomial algorithm based on the content of a super-frame of data. When CRC-6 checking is enabled via DIP
switch SW2–4, an alarm will be activated whenever a CRC code (checksum) is received over the ESF data link
that does not match the locally calculated code (checksum).
Yellow Alarm During ANSI Messages On The Facility Data Link
The facility data link is available for reporting transmission performance information once a second. Normally,
these transmissions are inhibited by yellow alarms. However, you can set DIP switch SW2-5 to allow these
transmissions during yellow alarms.
Green B8ZS/COFA LED Definition
The green LED on the DXPT1 board’s edge-panel labeled “B8ZS/COFA” indicates either that B8ZS code words
are being received or that a change of frame alignment (COFA) occurred during the last synchronization by the
external T1 source or carrier equipment. You can determine which condition you want reported by how you set
DIP switch SW2–6. The default setting is for “COFA” reporting.
IMI89–255
Installing And Programming The DXPRI Card
8 – Setting The T1/PRI Switches
Содержание DXP Plus Series
Страница 1: ...Digital Communications System R ...
Страница 363: ...Automatic Call Distributor Technical Manual R QuickQ DXP ...
Страница 424: ...Automatic Call Distributor System Manager s Guide R QuickQ DXP ...
Страница 500: ...Wrap up Time 1 6 Wrapping Up A Call 4 3 Z Zoom Box A 2 GCA70 271 Index I 3 ...
Страница 628: ...Interconnecting The VMI X Installing And Programming For ExecuMail IMI89 206 Installing And Programming For ExecuMail 5 ...
Страница 677: ...Connecting The Equipment Installing And Programming The OPX X IMI89 209 Installing The OPX X 7 ...
Страница 728: ...DP I I I I and FX Series Digital Communications Systems Understanding The Visual Man Machine Interface COMDlA ...
Страница 1112: ...9 08 8 90 1 13 4 78 3 94 UNIS029 TAB003 PLS page 6 GCA40 130 DXP Plus General Description 11B Telephone Features ...