On 21 May 98 at 20:56, Frank B Smith wrote:

> It has been awhile since I've had to communicate directly with my modem, and
> I seem to have forgotten whatever it was I knew....
>
> Upon occaision, my modem ( Rockwell k56flex) fails to hang up.  It rings,
> gets a busy signal and doesn't hang up.  However the dialer will attempt to
> re-dial and receives a "no dialtone" response.  Meanwhile the line stays
> open until the phone line begins making it's off hook complaint... which has
> no effect on the modem.
>
> Any suggestions?  i.e. is the darn thing showing signs of eventually
> dropping dead, or is it a simple software thing?

  I believe the S7 register contains a setting of "number of seconds
to wait for carrier".  The modem should hang up if it cannot
negotiate a connection within this time.  45 seconds is a common
setting, and may be the default.
  It sounds like your modem wants to wait forever, and that may mean
that it thinks it is supposed to ignore this timeout.  Although I
don't think I've ever seen it as a documented setting, this is a
reasonable thing for the modem to do if the value in S7 is 0.

  Since I haven't seen this documented, and since it's fairly
unlikely that you (or the author of some program you've used) would
do this on purpose, this may indicate a problem with the modem not
retaining S-register settings.  Especially, if adding "S7=45" to your
modem initialization string doesn't correct the problem, it may
indeed be a hardware failure.
  [Some modems recognize a command which tells them to report the
contents of all of their S-registers.  Without the manual for yours,
I can't tell if it does, but if it does I would check to see if other
values are also 0....]

  My Dad was telling me just the other night about a utility for DOS
and Win16 called "Modem Doctor" (look for MODEMDR.*).  I haven't had
a chance to try it out yet, but I think it might help in this case.

David G