usr.sbin/i4b/isdntrace/cable.txt

   1  *---------------------------------------------------------------------------
   2  *
   3  *      Custom cable to trace an ISDN S0 bus with two passive (!) ISDN boards
   4  *      ---------------------------------------------------------------------
   5  *
   6  *      $Id: cable.txt,v 1.4 1999/12/13 21:25:26 hm Exp $
   7  *
   8  * $FreeBSD: src/usr.sbin/i4b/isdntrace/cable.txt,v 1.6.2.1 2001/08/01 17:45:08 obrien Exp $
   9  * $DragonFly: src/usr.sbin/i4b/isdntrace/cable.txt,v 1.2 2003/06/17 04:29:55 dillon Exp $
  10  *
  11  *      last edit-date: [Mon Dec 13 21:55:42 1999]
  12  *
  13  *      -hm     documentation of analyze mode
  14  *
  15  *---------------------------------------------------------------------------*/
  16
  17 The cable consists of a RJ-45 plug with both tx and rx connected and
  18 two jacks; the tx cables from the plug are wired to one jack and the
  19 rx cables from the plug are wired to the other jack.
  20
  21 The computer must be equipped with two (!) supported passive cards and
  22 the cable from one card is plugged into one of the jacks while the cable
  23 to from the other card is plugged into the other jack.
  24
  25 Now one card monitors the tx part of the S0 bus and the other card
  26 monitors the rx part.
  27
  28 Which card functions as the rx side and which as the tx side can be
  29 specified as options to the isdntrace utility (-R and -T) which has
  30 to be run in analyzer mode (-a) to support this configuration.
  31
  32
  33                                               1
  34                                               2
  35                                               3
  36                                +--------------4     receiving-side board
  37   S0-bus                    +--|--------------5     in computer (jack for
  38   to analyze                |  |              6     cable to passive controller)
  39                8            |  |              7
  40                7            |  |              8
  41     transmit - 6------------|--|--+
  42     receive  - 5------------+  |  |
  43     receive  + 4---------------+  |
  44     transmit + 3------------+     |
  45                2            |     |           1
  46                1            |     |           2
  47   plug into                 |     |           3
  48    S0 bus                   +-----|-----------4    transmitting-side board
  49                                   +-----------5    in computer (jack for
  50                                               6    cable to passive controller)
  51                                               7
  52                                               8
  53
  54
  55
  56            RJ-45 plug                        RJ-45 jack
  57         view from the front              view from the front
  58     cable goes out to the rear
  59
  60           /--------- /                      ----------
  61          | 87654321 |                      | 12345678 |
  62          |__      __|/                     |/_      /_|
  63             |____|/                           |/___|