[asterisk-users] Problem with detecting fax on PRI/DAHDI channels

[Eric Wieling]

> -----Original Message-----
> From: asterisk-users-bounces at lists.digium.com
> [mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of
> Kevin P. Fleming
> Sent: Thursday, June 23, 2011 11:41 AM
> To: asterisk-users at lists.digium.com
> Subject: Re: [asterisk-users] Problem with detecting fax on
> PRI/DAHDI channels
>
> On 06/23/2011 09:12 AM, Sawan Vithlani wrote:
> > Hello all,
> >
> > I am using  call files to dial out to a set of PSTN
> numbers. The calls
> > are going out fine and being handled correctly by the dial plan.
> >
> > The problem occurs when I accidentally call a fax machine. I would
> > expect the dial plan to pick this up and jump to the "fax"
> extension
> > in the current context. This is not happening.
> >
> > In the call file I send the call out via
> Dial(DAHDI/g0/XXXXXXXX) and
> > then it goes to my dial plan context:
> >
> > [SendCall]
> > exten =>  start,1,Answer()
> >     same =>  n, Wait(5)
> >     same =>  n, ..... ;; do some more stuff
> >
> > exten =>  fax,1,Verbose(got a Fax on ${EXTEN}) same =>n, Hangup()
> >
> > ;;;;
> >
> >   I do get a message on the CLI telling me "Channel 63
> detected a CED
> > tone from the network" but still no jumping to the fax extensio

n.
> > This is while dialplan is in the Wait(5).
> >
> > CLI>  core show version
> > Asterisk 1.8.4.1-1digium1~natty built by pbuilder @ nighthawk on a
> > x86_64 running Linux on 2011-05-23 22:05:17 UTC
> >
> > ISDN lines connected via Digium TE412P card.
> >
> > I have "faxdetect = both" in chan_dahdi.conf in the general
> section as
> > well as specifically for the configured spans.
>
> 'faxdetect' is for detecting *calling* FAX machines, not
> *called* FAX machines. It listens for the CNG tone generated
> by a (non-V.34) calling FAX terminal.
>
> If you are wanting to detect that a number you have dialed is
> being answered by a FAX machine, there are applications
> available (but not included with Asterisk) to do that. I
> believe NVFaxDetect can do it, and most of the add-on
> answering machine detection applications can do it as well.

What is faxdetect=outgoing and faxdetect=both do?