[asterisk-users] GSM Gateway behind SIP ATA?

[Atis Lezdins]

Remco Barendse wrote:
> I have an analog GSM Gateway that is connected to a normal SIP ATA device.
> 
> Basically what it does is this : when you call the extension nr. of the 
> SIP ATA port, the GSM Gateway will pick up the phone and presents a (new) 
> dial tone, and then dials whichever DTMF tones it received. The SIP ATA ia 
> a Grandstream HT286.
> 
> I would like to use the GSM Gateway to route my outbound cellular calls, 
> how do i do this in Asterisk? Basically Asterisk should dial the extension 
> number and then send required number as DTMF tones to the Gateway through 
> the ATA.
> 
> I am using FreePBX, which allows me to create a custom trunk for the 
> outgoing calls. Hope this could work :)

This should work:

context out-gateway {
	_X. {
		Dial(SIP/gateway,30,M(dial-gateway^${EXTEN}));
	}
}

macro dial-gateway(number) {
	Wait(1);
	SendDTMF(${number});
}

You dial to gateway, and execute macro upon answer (if i remember 
correctly, it should be executed within dialed channel), so macro sends 
the number you need to dial on GSM gateway in DTMF, and after that 
bridges the call. You might try removing the Wait(1), but your GSM 
gateway could expect some idle time before receiving digits so i put it 
there.

Regards,
Atis