Question

I want to replace a legacy GSM/2G modem by the TRB140 (S/N 1108578849 - FW TRB1_R_00.02.05.1 - Kernel 3.18.20-msm).

My SW application (in LINUX - not to be changed) must connect permanently in TCP/IP RAW connection to the modem to send SMS via AT commands (alarm texts) . Through this permanent connection it must also detect incoming call (RING): the incoming call / RING will simply acknowleged the alarm in my application.

TRB140 seems a nice/complete device but I have not found how to connect to the modem directly through the network: typically this is often port 2101 (telnet) or port 2001 (tcp raw) connection.

Could you confirm that this use case is possible. Please redirect to the correct documentation ressources or describe how to do.

(in other words I want to do something very basic / simple to replace a legacy HW)

Thanks in advance, pg

Answer 1

Hello,

You could establish a connection between TRB140 and your device using SSH connection and send AT commands this way. There is a list of supported network protocols: 

TCP, UDP, IPv4, IPv6, ICMP, NTP, DNS, HTTP, HTTPS, SSL v3, TLS, PPP, SSH, DHCP, MQTT, Wake on LAN (WOL)

Comments

Dear Vykintas,

Thank you for your return … but it is not corresponding to my question (please reread again my explanations).

I need to connect to the modem directly through the network and type AT commands (and not first do a ssh connection and then use your propietary gsmctl commands).

Normally all equipments ('network modems') like TRB140 offer the possibility to connect to a 'special network port' (i.e. RAW/TCP port 2001) to connect directly to the modem... 

Thanks in advance for your extended response.

br, pg

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Hi Vykintas, any update on this? I have the same issue, I want to send AT commands to the modem directly from a basic PLC via RAW TCP. 

Thank you!