[comp.dcom.modems] Telebit T1000 problem.

smitty@essnj1.UUCP (Hibbard T. Smith JR) (05/26/90)

I've been using a Telebit T1000 for a year now, and I like it a lot.  My 
system is a 386 25Mhz running ISC 2.0.2 with the X5 upgrade installed.  I have 
the Dialers and Devices files configured to lock the T1000 to the speed of
the Systems file entry for the particular system being called.  The T1000
is configured to reset to the stored profile when DTR drops at the end of the 
call.  The stored profile allows the modem answer speed to float in response
to incoming calls.

The problem is that after an outbound call, the modem will not float to the
speed of an incoming call.  It only offers the speed at which the preceeding 
(outbound) call was made.  Apparently the speed lock is remaining in effect,
and the stored profile is not being obeyed.  I've checked with a scope, and 
the system drops DTR for a couple of seconds.  If I drop DTR manually, or 
power down and up the modem, the "float" works properly.

Any help I can get with this would be deeply appreciated.  It's causing some
incoming calls to be answered (ie paid for), but not connected.  This is 
a source of irritation for some of my users.  Please email responses, unless  
you feel it's of general interest.  I'll follow this group watching for
followups.

Thanks in advance for any help.
-- 
		Smitty
-------------------------------------------
Hibbard T. Smith JR                 	 ESSNJAY Systems Inc.
uunet!hsi!essnj1!smitty

andy@rbdc (Andy Pitts) (05/29/90)

smitty@essnj1.UUCP (Hibbard T. Smith JR) writes:

[...]

>The problem is that after an outbound call, the modem will not float to the
>speed of an incoming call.  It only offers the speed at which the preceeding 
>(outbound) call was made.  Apparently the speed lock is remaining in effect,
>and the stored profile is not being obeyed.  I've checked with a scope, and 
>the system drops DTR for a couple of seconds.  If I drop DTR manually, or 
>power down and up the modem, the "float" works properly.

[...]

>Thanks in advance for any help.
>-- 
>		Smitty
>-------------------------------------------
>Hibbard T. Smith JR                 	 ESSNJAY Systems Inc.
>uunet!hsi!essnj1!smitty

This should be of general interest.

In some versions of the firmware for the Trailblazer Plus, there exists
a bug which causes the modem to ignore transitions of DTR, if DTR drops
at the same time or immediately after the modem drops DCD.  This sounds
like what you are describing.  I don't know if this problem exists in
the T1000.  I would suggest that you call Telebit and ask them.  They
are quite helpful.

Disclaimer:  I have one of their modems...Beyond that, I have nothing
to do with Telebit.
-- 
Andy Pitts andy@rbdc.UUCP  : "God is an overwhelming responsibility"
...!emory!kd4nc!rbdc!andy  :            --Jethro Tull--