vgetty won't do a data connect

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Hi,

Canary, Robert W. wrote:
> vgetty answers the call just fine.  Plays the message back just fine. (does 
> not record well at all; another question for tommorow) But,  if it is a 
> dialin conntection vgetty goes into a dial in connection after palying the 
> OGM and then sits there.  Meanwhile the modem dialing in say that the 
> modem(the vgetty modem) it is calling is not responding. And I never make 
> the connection.  I really don't know what ask here except is there away to 
> tell vgetty to give first consisdersation to a data connection?  (if that 
> will fix the problem)

While I'm not a voice expert, let me note a few things.

Many modems send a CNG tone ("calling tone") when calling another modem.
Voice modems can listen to that tone, while playing their own greeting
message, and notify vgetty of that ("I found a DATA [FAX] CNG tone, let's
switch over to that").

Problems usually start if you call with an oldish modem that doesn't send
a CNG tone.

In that case, vgetty can't do more than "play the OGM in its full length,
start recording, detect silence, and try to go to data/fax".  Data/fax
detection now done by "just sending out carriers and see whether anything
respons".  This method is clearly inferiour, *especially* because the time
between picking up the phone and starting to send a carrier is very long
(it's the whole length of the OGM plus some seconds of recording
silence).  Many calling modems give up if they don't hear a carrier for
long periods of time, and I think this is what happening.


To work around this, you could make the calling modem send a DTMF tone
while the OGM is playing ("ATD12345,,,,1" - dial the number, "dial" a lot
of commas for delay, send an "1" digit).


If it still doesn't work, we would need to see the vgetty log file (only
the lines after "waiting for RING").

gert

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Gert Doering - Munich, Germany                             gert@greenie.muc.de
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