data call and greeting-message

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Hi,

Robert J. Brown wrote:
> >>>>> "Matthias" == Matthias Prinz <matthias@Tintin.Rhein-Main.De> writes:
> 
>  Matthias> If I understand the documentation right, a data-call
>  Matthias> should be recognized while the message is played, even
>  Matthias> in the latest version.
> 
> If I am not mistaken, the answering modem is responsible for issuing
> the answer-back tone (first note of the "whale song"), and only then
> does the calling modem begin to send tones. 

Uh, this was true in 2400 baud age ... nowadays, all recent fax machines
and modems send a calling tone (CNG) right after they have finished 
dialing. Voice modems recognize these tones, and signal them to the
vgetty process (<DLE><something>), different codes for fax CNG or for
data CNG.

> If this is true then it
> is not possible for the data call to be recognized while the voice
> greeting is being played, because the calling modem is silent until it
> hear that old familiar voice of those answer-back tones.

Except for some oldish modems or manually-dialed fax machines, this should
be no longer true.

gert

-- 
Gert Doering
Mobile communications ... right now writing from *AWAY* :-)) 
... mobile phone: +49 177 2160221 ... or mail me: gert@greenie.muc.de
.