[asterisk-users] setup for fax machine

Gordon Henderson
Mon, 13 Oct 2008 06:25:12 -0000

On Sun, 12 Oct 2008, sean darcy wrote:

> Becasue of all the issues with fax over voip, we want to use pstn for
> our fax machine, but not dedicate a line just to fax.
>
> I'm thinking of having asterisk answer the pstn line, check for fax
> tones, and route appropriately. In zapata ( chan_dahdi ) set
> faxdetect=incoming
>
> then the dial plan would have
>
> [incoming-pstn]
> exten => fax,1,Dial(DAHDI/1)  ; the fax machine
> exten => fax,2,Hangup()
>
> exten => s,1,Answer()
> exten => s,2,Dial(DAHDI/2)   ; internal extension
> .............
>
> Would this work? I'll need another TDM410 card to do this, so I'd
like
> some reassurance before I go purchase it.

You need to Answer() the call first, then insert a Wait(2). During that
time, asterisk will be listning for fax tone and jump to the fax extension
if it hears them.

So:

exten => s,1,Answer()
exten => s,n,Wait(2)
   Ringing()
   Dial(DAHDI/2)
   Hangup()

and

exten => fax,1,Dial(DHADI/1)
exten => fax,n,Hangup()

But at this point why not just feed it into RxFax?

Gordon