Curt writes:

> I am trying to move a modem that worked connected to a DTC16 (direct connect
>  card) to a DTC16mx (DDP-2 rs-232 connection panel).  I have tried 4
>  different configurations and none seem to work.
>
>  I have changed the port 0-7 to modem instead of direct. Have set modem type
>  to 1, tried modem behavor 1,2, and 3.  Parity is none.  I never see the TR
>  light come on and the modem never answers when called.
>
>  Can anyone shed some light on what I am doing wrong?

The DTR (data terminal ready) light is lit when the HP3000 commands it to be
lit. DTR is a signal to the modem that the host is ready to receive calls on
the modem. It is also the signal line that the HP3000 uses to hang up the
modem connection when a :BYE command is issued.

A standard modem will not answer a phone call while the DTR signal is absent,
although you can program virtually all modems to falsely set the DTR line
high, essentially making the DTR signal wire irrelevant.

If you have connected the modem to a non-modem capable port on the DTC (the
DTR signal isn't even electrically present) and you have your modem programmed
(as it should be) to observe the status of the DTR line, then the DTR light
will never light and your modem will never answer.

Wirt Atmar