Black Box ME758C-RJ45, ME759C-RJ45, May-95, ME759C-RJ11, ME758C-RJ11 Remote Digital Loopback RDL

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MULTI-FUNCTION LD CARD

4.If the BERT test indicates no errors are present, move the “511/E—511” toggle switch to the left-hand position to activate the “511/E” test with periodic errors. If this test is working properly, the Error LED will blink regularly. A successful 511/E test will confirm that the loop is in place, and that the Multi-Function LD Card’s built-in 511 generator and detector are working properly.

5.If the BERT test indicates that errors are present, make sure that the RS- 232 cable connecting the DTE to the Multi-Function LD Card is wired straight-through, and is plugged in properly. Also, make sure that the Card is configured properly. Then recheck your DTE equipment. If you still get errors and can’t find the cause, call your supplier for technical support (see Section 6.1).

5.4.2REMOTE DIGITAL LOOPBACK (RDL)

The Remote Digital Loopback (RDL) test checks the performance of both the local and remote Multi-Function LD Cards, and the communication link between them. Any characters sent to the remote Card in this test mode will be echoed (returned) back to the originating device. For example, characters typed on the keyboard of the local terminal will appear on the local terminal’s screen after having been passed to the remote Multi-Function LD Card and looped back. To perform an RDL test, follow these steps:

1.Activate RDL. You can do this in either of two ways. One is to move the upper front-panel toggle switch labeled “Remote—Analog” to the “Remote” (left-hand) position. The other is to raise the signal on

Pin 21 of the RS-232 interface (switch S3 position 6 must be “On”—see Section 3.1.4). Once RDL is activated, the remote Card’s receive input is connected to its own transmitter. The Test LED should light on both Cards.

2.Verify that the DTE attached to the local Card is operating properly and can be used for a test.

3.Move the lower front-panel toggle switch labeled “511/E—511” to the “511” (right-hand) position. This will activate the V.52 BERT test mode and inject a 511 test pattern into the remote loop. If any errors are present in the loop, the Error LED will blink sporadically.

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Contents Multi-Function LD Cards FCC Statements MULTI-FUNCTION LD Card NOM Statements Contents Specifications Connectors IndicatorsDiagnostics Fuse PowerTemperature WeightOverview FeaturesIntroduction Introduction Main-module switches Setting the Switches on the Main ModuleSwitch S1 Summary On and OFF settings of the DIP switchesS1 Position 7 Protocol S1 Positions 1 through 4 Data-Rate SettingS1 Positions 5 and 6 Clock Source S1 Position 8 Carrier-Control Method Switch S2 SummaryS2 Position 2 2-Wire vs -Wire Operation S2-7 and S2-8 Word Length S2 Position 3 V.52 and V.54 Diagnostic TestingS2 Positions 4 and 5 RTS/CTS Delay S2-6 Signaling-Rate RangeS3-1 and S3-2 Input Impedance Switch S3 SummaryS3-6 DTE RS-232 Initiation of Remote Loopback Test Recommended Impedance SettingsS3-4 Mode Selection S3-5 DTE RS-232 Initiation of Local Loopback TestS3-7 and S3-8 Antistream Control Setting the Jumpers on the Interface ModuleFour interface modules Jumper locations Line Interface Line Shield Connection to Frame Ground JB2 Summary of Interface-Module Jumper FunctionsJB5 Serial Interface Signal Ground and Frame Ground JB4MicroRacks An Overview InstallationMicroRacks’ Power Supply Installing the Multi-Function LD Card in the MicroRack Pinout of the 10-Pin RJ Interface RS-232 Serial Cables and ConnectorsPinout of the RS-232 Interface Modem-to-Modem Line Cables and Connectors AT&T standard modular color codes Line-Cable PinoutsMultipoint Applications Two-pair star wiring for host and slave CardsStatus LEDs Operation and DiagnosticsRTS and CD Indicators Diagnostic Testing Using the Error LED Power-Up V.54 and V.52 Diagnostic Tests Remote Digital Loopback RDL Using the V.52 Bert Test Independently Shipping and Packaging TroubleshootingCalling Your Supplier Appendix Cable Recommendations Wire Gauge Capacitance ResistanceMULTI-FUNCTION LD Card Copyright 1995. Black Box Corporation. All rights reserved
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