American Telecom AM64/128A manual Binary Patterns, Remote loop from DTE, Bin Keys Off Sending Bin

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AM64/128A User Manual	Test Menu

5.4.3.2 Remote loop from DTE

When the BBM receives an ART pattern (00110011) from the DTE (in X.21), or when circuit 140 is active (in X.21bis) the loopback is applied on the remote BBM similarly to the above. To apply a remote loop in this fashion refer to your DTE handbook for details.

The BBM can be in any menu when this loop is applied, it does not have to be in the Test Menu.

Note that the Test Menu Rem Loop message does not reflect the state of a loop applied from the DTE, but the status menu display and the TM LED will be set as in the above case.

The data flow with the loop applied is shown in figure 5.4.3.

It is possible to have a BBM menu selected remote loop operational at the same time as a DTE remote loop. In this case the loop itself will only be removed when both the menu item has been deselected and the DTE has cancelled its loop, (i.e. the loop is removed by the last releasing action).

5.4.4 Binary Patterns

It is possible to transmit three different patterns to the remote BBM:

(1)All 1's with status ON

(2)All 0's with status ON

(3)Alternate 1’s and 0’s with status OFF (Controlled Not Ready’s or CNR’s)

The CNR pattern (3) is sent by pressing ‘TX NRDY’ on the front panel. Patterns (1) and (2) can only be activated from the test menu.

Default state is sending no patterns when the display is :

If the SELECT key is pressed then binary 0's are sent :

T> Bin Keys Off

T> Sending Bin 0

If the SELECT key is pressed again then the binary 1 pattern is sent :

T> Sending Bin 1

A third press of SELECT returns the function to its default (off) state.

Note : several factors may prevent the binary pattern being transmitted. The test menu display shows only that a binary pattern will be transmitted if the BBM is capable of it.

Factors preventing transmission are:

(1)Fault conditions

(2)Loop back active

(3)Local loop active

(4)TX NRDY key active

With most rates the patterns are sent with status ON. If an unstructured rate, such as 64kbps, is used, there is no status line. In this case binary 1’s become effectively a AIS signal, and binary 0’s become a UNR signal.

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Contents Base Band Modem ATL Part No /203/002/610 Issue 4 SeptemberInformation Contained This Document is Confidential to Contents Appendix B International Models IntroductionConstructional Details Baseband ModemsInterface Modules System Overview System Overview Testing InstallationBBM to BBM Link Self Test PassLink Mode LTU Ready No Alarm LTU Not ReadyBBM to Line Card Link Network ModeMenu Operation Front Panel FeaturesLoop back On Loop back OffStatus Menu Over all StatusLoop Active No Alarm No Signal Receiving AIS No Alignment Alarm StatusLOS/CD Fail CD FailUser Rate Line RateInterface Status Link Mode Network Mode Operating ModeLocal loop Test MenuLocal loop from menu Top level display shows Loc Loop Off Loc Loop OnLocal loop from DTE LoopbackLoopback is applied by selecting the display Loopback Off Loopback OnRemote Loop from menu Remote LoopRem Loop Off Rem Loop OnBinary Patterns Remote loop from DTEBin Keys Off Sending Bin Data Test Error Count Bit Error Rate BER = User Data Rate x TimeOverview OperationErrors s000001 Errors nnnnnnErrors Data TestTransparent Mode Injection ModeInjecting 0s Injecting 1sSvc Test Service TestComms Evp Rx Evp Tx Time If the count is stopped the display is StopSelf Test Lamp TestComm Loop Off Communication Channel LoopbackRate 4.8K Rate MenuMaster 64K BT Slave 4.8K 2 X.21bis Option MenuAsynchronous Mode Signalling Rate3 G.703 Char Len Character LengthConfiguration Menu Master SlaveLine Rate 3 X.21 Loop Control ModemSynchronisation Type for software versions below Ext Byte Clk Synchronisation Type for software version V1.3 and aboveExt Bit Clk Internal Clk5 64k Mode Power LevelMenu Lock Glossary of Terms Band circuits General Specifications Way D type X.21 bis V.24 / V.28* Connector pin allocation Way D-type X.21 V.11 Connector pin allocationAppendix a Interface Pin Connections Way D-type V.36 Connector pin allocation Mrac Connector Pin allocationLine Connector Way D-type RS-530 Connector pin allocationAppendix B Internal Link Settings Page Interface Module Interface Modules21bis Interface Module RS530 Interface ModuleFrame Structure Service Test FacilitiesAppendix C In Service Test TTE Network and Safety statements LVD Safety Statements21 bit timing cable 15 way to 15 way D type plugs Appendix E21 byte timing cable 15 way to 15 way D type plugs 24 / V.28 bit timing cable 25 way to 25 way D type plugs35 bit timing cable 34 way to 34 way Mrac plugs RS530 bit timing cable 25 way to 25 way D type plugs 21 bis V.36 bit timing cable 37 way to 37 way D type plugsAppendix F Troubleshooting Power 10dBm Slave Mode 64K RateMaster Mode C 64K Rate Rate 64K