DUA1:<SYS0.SYSMAINT>EHXDL.HLP;1
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1 HELP
  EHXDL
                            
        This program checks the functionality of the DLVJ1  providing
        error messages that may aid in the repair of the device.  The
        diagnostic uses  the internal  loopback mode to check most of
        the circuitry of the device.

1 DEVICE

        This program will be runnable only on a MicroVAX I computer and with
        a VAX Diagnostic Supervisor of version  6.12 or later.  This program
        is a level 3  functional  diagnostic and will not support any device
        other than the DLVJ1.
   
2 DLVJ1

  Description:   DLVJ1 Asynchronous four-line communications interface
  link:      HUB
  Generic name:  TTa
  Additional information:
     QBUS CSR [octal 760000-777776]<776500>
     QBUS vector [octal 2-776]
     Number of data bits configured [7 or 8]<8>
     Number of stop bits configured [1 or 2]<1>
     Parity detection enabled <no>
     Even parity enabled <no>
  Tested by: EHXDL

1 REQUIREMENTS

  HARDWARE:            MicroVAX I processor with 512Kb of memory
                       DLVJ1 dual size board


  OPTIONAL HARDWARE:   H3270-A  turn around connector
                       Another terminal

  SOFTWARE:            Vax Diagnostic Supervisor V6.12 or later


1 EVENT

  There are no user-settable event flags.

1 QUICK

  This diagnostic does not use the VDS QUICK-pass flag.

1 SUMMARY

  This diagnostic does not produce a summary report.

1 MANUAL

  Test section ECHO (test 9) requires manual intervention.  An additional
  terminal must be connected to one of the channels  and the operator must
  enter characters finishing with a control-z to complete the test.

1 SECTIONS


  There are five sections to this diagnostic.   Sections "LOOPBACK" and
  "ALL" require an H3270-A loopback connector.  Section "ECHO" requires
  another terminal and manual intervention.

2 DEFAULT

  Used for minimal testing.  This section includes tests 1, 2, and 4.
  Logic not requiring any loopback is tested.

2 REGISTER

  Used for minimal testing.  This section includes tests 1, 2, and 4.
  Logic not requiring any loopback is tested.  This is exactly the same
  as the DEFAULT section.

2 LOOPBACK

  Used to test internal loopback.  Requires an H3270-A loopback connector.
  This section includes tests 3, 5, 6, 7 and 8.

2 ALL

  Used to test all internal circuitry.  Requires an H3270-A loopback
  connector.  This section includes tests 1, 2, 3, 4, 5, 6, 7 and 8.

2 ECHO

  Used to verify communications with an external terminal.  Requires
  manual intervention and another terminal.  The operator is requied
  to respond to one question  on the console and to enter characters
  on the external terminal.   The test completes when a control-z is 
  entered.  This section includes test 9 only.

1 ATTACHING 


  The following is an example of how to attach the device to be tested,
  and to load and run EHXDL (answers to hardware questions are typed in
  octal).

  DS> LOAD EHXDL                  ; load the diagnostic
  DS> ATTACH DLVJ1                ; attach the DLVJ1
  Device link? HUB                ; the option is linked to HUB
  Device name? TTA                ; the option is named unit A (range=A-Z)
  CSR? 776500                     ; the csr address is 776500
  Vector? 300                     ; vector address is 300 (range=000-770)  
  Number of data bits? 8          ; 8 bits per character
  Number of stop bits? 1          ; 1 stop bits
  Parity detection enabled? YES   ; parity enabled
  Even parity enabled? NO         ; even parity not selected (odd parity)
  DS> SEL TTA                     ; select device
  DS> START                       ; start the diagnostic

