LPWA - App Minicom for serial communication

  • The required UART drivers are usually distributed as part of the Linux kernel since v4.4.132.

  • Check whether the required kernel module is loaded: lsmod | grep option.

  • Check whether you have read/write access to USB-UART bridge: ls -la /dev/ttyUSB*.

With the Minicom app

Step 1: Install Minicom

sudo apt install minicom

Step 2: User must belong to the 'dialout' group

Check with:

groups USERNAME

If dialout is not listed then:

sudo usermod -aG dialout USERNAME

For the changes to take effect, log off the user and log on again

Step 3: Then you can connect to the device:

minicom -D /dev/ttyUSB1

Step 4: Send AT Command to USB Connect LPWA

ATI

Step 5: Wait of response from USB Connect LPWA

Manufacturer: u-blox Model: SARA-R410M-02B Revision: L0.0.00.00.05.08 [Apr 17 2019 19:34:02] SVN: 03 IMEI: 352753099064196 OK

Useful link:

Getting Started With Minicom - Getting Started With Minicom

Linux setup & troubleshooting

Currently, the ModemManager package (confirmed for version 1.10.0-1~ubuntu18.04.2) detects the USB Connect LPWA (R410) as a general QMI-WWAN modem and tries to configure it. Besides failing this task it blocks any "user" AT commands, e.g. using minicom.

The following shell commands stop and disable the ModemManager service: