AT Console over USB-C

This page shows you how to communicate with GLIDER through its USB-C connector using AT commands. The AT console is the recommended interface for everyday work (provisioning, configuration, firmware updates) and requires no special debug hardware.

tip

Looking for live logs and the full Zephyr shell? Use the RTT Console (J-Link) instead.

How it works

Internally, GLIDER pipes UART0 of the nRF9151 to an FT234XD USB-UART bridge chip. The moment you plug in a USB-C cable, the firmware powers up the bridge and starts accepting AT commands.

Signal	nRF9151 pin	Function
UART0 TX	P0.25	nRF91 → FT234XD RXD
UART0 RX	P0.24	nRF91 ← FT234XD TXD
USB_EN	P0.00	Powers the FT234XD (active high)
USB_DETECT	P0.26	Detects the cable (active low)

UART0 runs at 1 000 000 baud (configured in gauger_lte_nrf9151_common.dtsi).

When you connect the USB-C cable the firmware:

1. Detects the cable on USB_DETECT (P0.26).
2. After a 50 ms debounce, turns on USB_EN (P0.00), and the FT234XD boots.
3. Activates UART0 RX and starts processing AT commands.

Prerequisites

System packages

sudo apt update
sudo apt install python3 python3-venv git

Membership in the dialout group

Linux restricts serial port access to members of the dialout group. Add yourself once:

sudo usermod -aG dialout $USER

caution

You must log out and log in again for the group change to take effect. Verify with:

groups | grep -o dialout
# should print: dialout

Verify the USB-C cable enumerates

Plug in GLIDER and check:

ls -l /dev/ttyUSB0
# crw-rw---- 1 root dialout ... /dev/ttyUSB0

If /dev/ttyUSB0 does not appear, check dmesg | tail -20. You should see something like:

usb 1-2: new full-speed USB device
ftdi_sio 1-2:1.0: FTDI USB Serial Device converter detected
usb 1-2: FTDI USB Serial Device converter now attached to ttyUSB0

If you see errors instead, the issue is hardware-side (wrong cable, faulty connector, FT234XD not getting power).

Full setup with a Python virtual environment

The recommended way to install the HARDWARIO command-line tools is inside a Python virtualenv. This isolates the packages from your system Python and works on every modern Linux distribution.

Step 1 - Verify python3-venv is installed

dpkg -l python3-venv | tail -1
# expect a line starting with "ii"

If it is missing:

sudo apt install python3-venv

Step 2 - Create the virtualenv

Inside your project folder:

python3 -m venv .venv

Step 3 - Activate the virtualenv

source .venv/bin/activate

Your shell prompt should now be prefixed with (.venv).

Step 4 - Install the required packages

pip install --upgrade pip
pip install west pyserial loguru rttt

What you just installed:

Package	Purpose
west	Meta-build tool used by Zephyr / nRF Connect SDK
pyserial	UART communication library
loguru	Structured logging
rttt	HARDWARIO console UI library that parses the @LOG: framing

Step 5 - Verify the installation

west --version
python3 -c "import serial, loguru, rttt; print('OK')"

Both commands should succeed.

Launching the console

In a terminal where the virtualenv is active:

source .venv/bin/activate
west serial-console

Defaults used by west serial-console:

• --port /dev/ttyUSB0
• --baudrate 1000000

If you have multiple devices, specify the port explicitly:

west serial-console --port /dev/ttyUSB1 --baudrate 1000000

The console keeps two streams separated:

• AT commands and responses: what you type and what GLIDER replies.
• @LOG: messages: live log lines that scroll past without interfering with the command line.

Useful files maintained by west serial-console:

• Command history: ~/.serial_console_history
• Full session transcript: ~/.serial_console_console
• Modem trace: ~/.serial_console.mtrace

A quick sanity check

AT
# OK

ATI
# "GLIDER-R1.1"

If OK appears, you are talking to the device.

Basic AT commands

Command	What it does
AT	Connection test, returns OK
AT+CLAC	Lists all registered AT commands
AT$HELP	Same as +CLAC but with hints
ATI	Device identification
AT+CGMI	Vendor name
AT+CGMM	Product name
AT+CGMR	Firmware revision
AT+CGSN	Serial number
AT$INFO?	Dump of all info fields (serial, claim token, …)
AT$REBOOT	Restart the device
AT&W	Save configuration to flash
AT&F	Factory reset (wipes all configuration)

Configuration over AT

AT$CONFIG=? # list every configurable key
AT$CONFIG="therm config show" # current thermometer slot bindings
AT$CONFIG="therm config 1 28ab12cd…" # bind slot 1 to a specific DS18B20
AT&W # save and reboot

Running shell commands from the AT console

The AT console can also execute any Zephyr shell command via AT$SHELL:

AT$SHELL="therm state"
AT$SHELL="therm scan"
AT$SHELL="therm scan --save"
AT$SHELL="kernel reboot cold"
AT$SHELL="log disable"
AT$SHELL="log enable wrn"

Firmware update

For a programmatic firmware update see the AT Commands reference (AT$FW).

Maintenance

Action	Command
Leave the virtualenv	deactivate
Upgrade the tools	pip install --upgrade west pyserial loguru rttt
Remove the virtualenv	rm -rf .venv
List installed packages	pip list

Troubleshooting

Permission denied on /dev/ttyUSB0

ls -l /dev/ttyUSB0
# crw-rw---- 1 root dialout ...

groups | grep dialout
# if "dialout" is missing:
sudo usermod -aG dialout $USER
# then log out / log in (or run: newgrp dialout)

The port is busy

Another terminal (screen, minicom, picocom, tio, …) is already holding it:

sudo lsof /dev/ttyUSB0
screen -ls && screen -wipe
killall screen minicom picocom tio 2>/dev/null

Logs arrive, but AT commands are not echoed back

Your terminal is sending CR only instead of LF or CRLF. west serial-console handles line endings automatically, but other terminals may not. For example, when using tio:

tio -b 1000000 -m INLCRNL,OCRNL /dev/ttyUSB0

OCRNL maps outgoing CR to LF.

Alternative terminals

If west serial-console is not available, any terminal that can do 1 000 000 baud works:

# tio (recommended alternative)
tio -b 1000000 -m INLCRNL,OCRNL /dev/ttyUSB0
# exit: Ctrl-T Q

# picocom
picocom -b 1000000 --omap crlf /dev/ttyUSB0
# exit: Ctrl-A Ctrl-X

# pyserial miniterm
python3 -m serial.tools.miniterm /dev/ttyUSB0 1000000
# exit: Ctrl-]