hello:
this is a link you can refer:
http://wiki.voip88.com/index.php/Linux/Freeswitch/Sangoma/PRI
please try to verify the CRC4 for specific service providers.

Best regards,
James.zhu
website: www.hiastar.com

> Date: Mon, 5 Aug 2013 02:22:00 +0530
> From: sravi123@yahoo.com
> To: freeswitch-users@lists.freeswitch.org
> Subject: [Freeswitch-users] Help with PRI Configuration - Bharti Airtel - Sangoma 101DE - Freeswitch
>
> Hello Everyone !
>
> I am from India. I have recently taken a PRI connection from Bharti
> Airtel, one of the service providers. I have installed the following:
>
> Cent OS
> Freeswitch, FreeTDM
> Sangoma Card
>
>
> I think, I have followed all the instructions. I am struggling to
> configure Freeswitch to start using the PRI connection. This is what I
> have from the freeswitch cook book, to configure the gateway: we need
> username/password, server address or IP and port.
>
> When I checked with Airtel, they are telling me that they only give
> username/password and IP address details for an internet connection and
> not for PRI lines.
>
> Has anyone here in the list, tried using an indian service provider and
> configured in Freeswitch?
> Has anyone done it for Airtel ?
> Or please help me to figure out how to configure the PRI so as to make
> inbound and outbound calls ??
>
> Any help is much appreciated.
>
> Thanks.
> Ravi
> +91-7502029000
>
>
> _________________________________________________________________________
> Professional FreeSWITCH Consulting Services:
> consulting@freeswitch.org
> http://www.freeswitchsolutions.com
>
> FreeSWITCH-powered IP PBX: The CudaTel Communication Server
> http://www.cudatel.com
>
> Official FreeSWITCH Sites
> http://www.freeswitch.org
> http://wiki.freeswitch.org
> http://www.cluecon.com
>
> FreeSWITCH-users mailing list
> FreeSWITCH-users@lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> http://www.freeswitch.org