Finding At Command Interpreter Device Files; Opening A Device File With A Terminal Program; At&T Only - Installing The Sim And Configuring The Modem's Packet Data Protocol (Pdp) Context - Multitech MultiConnect MTC-L4G2D User Manual

Finding AT Command Interpreter Device Files

The modem provides several serial USB interfaces which appear as TTY device files in /dev.
Two USB interfaces provide access to separate AT command interpreters running on the modem. One AT
command interpreter is used as the data channel for the PPP connection. The other may be used to poll the
modem for cellular network statistics.
To find which device files connect to the AT command interpreters on the modem, first list device files and then
select one to open with a terminal program.
List files:
$ ls -l /dev/ttyU*
crw-rw---- 1 root dialout 188, 0 Oct
crw-rw---- 1 root dialout 188, 1 Oct
crw-rw---- 1 root dialout 188, 2 Oct

Opening a Device File with a Terminal Program:

Note: The default serial baud rate for MultiTech products is 115200 baud. In this example the default baud rate for
minicom is also 115200.
$ minicom -D /dev/ttyUSB2
In the terminal program, type:
AT
and then press Enter.
The expected response from the modem is OK. No response indicates that the device file does not connect to an
AT command interpreter. Example of an AT command interpreter responding on /dev/ttyUSB2:
Welcome to minicom 2.8
OPTIONS: I18n
Port /dev/ttyUSB2, 23:17:13
Press CTRL-A Z for help on special keys
AT
OK
AT&T Only - Installing the SIM And Configuring the Modem's Packet Data Protocol (PDP)
Context
This configuration step should be done only once after installing a new SIM, updating firmware, or following carrier
changes to the cellular account provisioning for the existing SIM. Do not perform this step every time the network
is brought up.
Important: Verizon Configuration DO NOT perform this step for Verizon SIMs.Modems operating on Verizon
networks receive configuration information from the Verizon cellular network automatically.
Consult with the carrier to determine IP version and Access Point Name (APN) indicated in the following example.
If the network is IPv4 use "IP" , if it's IPv4/6 use "IPV4V6".
®
MultiConnect Cell MTC-L4G2D User Guide
6 23:17 /dev/ttyUSB0
6 23:17 /dev/ttyUSB1
6 23:17 /dev/ttyUSB2
USING LINUX WITH THE L4G2D RADIO
37