"John Clogg" <[log in to unmask]> wrote in message
news:a4bgsg01bo8@enews4.newsguy.com...
> I haven't used that modem, but I can pretty much guarantee the cable that
> came with it won't work.  First of all, you said it has a DB25 female
> connector, but the connectors on the DTC are female, so you would need a
> gender changer.  The second problem is that DTC ports are wired as DCE
> ports, not DTE, which means that pins 2 and 3 are reversed with respect to
> the cable's expected pin assignments.
>

In addition to the 2/3 mapping (data), the control and status lines will
need
special handling.  Note that the RS-232 Standard does not specify or even
require a connector at the DTE ("DTC") and only governs the pin assignments
at the DCE ("Modem") .  A "PC" modem cable is not correct unless you
modify it to match the DTC.  Page 2-34 in HP's DTC Cabling manual shows
the right connections and it works correctly--assuming you have the MODEM
control/status lines configured in an appropriate fashion.  I use these
connections
for both DTC and Remote Console connectivity, and the modems answer and
disconnect properly for both.  If either the cable connections or modem
settings are wrong, you will notice the modem either won't answer or won't
hang-up.

     DTC
MODEM

1   (Protective Gnd.)                                         1  (Protective
Ground)
2   (Receive Data - IN)                                     3  (Receive
Data - OUT)
3   (Transmit Data - OUT)                                 2  (Transmit
Data - IN)
4   (Carrier Detect - IN)                                    8  (Carrier
Detect - OUT)
6   (Data Terminal Ready - OUT)                      20 (Data Terminal
Ready - IN)
7   (Signal Ground)                                            7  (Signal
Ground)
8   (Request to Send - OUT)                             8  (Request to
Send - IN)
20 (Dataset Ready - IN)                                    6  (Dataset
Ready - OUT)
22 (Clear to Send - IN)                                     5  (Clear to
Send - OUT)

Winston K.

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