I’m using a RM520N-GL 5G modem, how can I send AT commands to the RM520N-GL modem by USB in Ubuntu?
Thank you.
I’m using a RM520N-GL 5G modem, how can I send AT commands to the RM520N-GL modem by USB in Ubuntu?
Thank you.
Please check whether you can see the ttyUSBx.
If the USB serial driver is ready, then you can use serial tool such as
microcom/minicom to send AT command.
lsusb -t
echo 2C7C 0801 FF | sudo tee /sys/bus/usb-serial/drivers/option1/new_id
sudo systemctl stop ModemManager
busybox micorcom /dev/ttyUSB2 -s 115200
I’m not sure if this operation is correct. I used UART with PuTTY to execute the following commands, but afterward, the keyboard stopped responding to any input. However, PuTTY didn’t crash and is still outputting device messages.
sudo apt install -y minicom
sudo apt install -y busybox
You can open the ttyUSB AT port with
minicom -D /dev/ttyUSB2
You have connected the PC with another usb serial device ,and the ttyUSB2 might not be the AT port.
sudo apt update
sudo apt install -y minicom
Is the PC X86_64 arch?
The PC is ARM64 arch.
$dpkg --print-architecture
arm64
Into minicom,
I tried serial device: /dev/ttyUSB0 through ttyUSB3, I just input “AT”, but no any reponse from AT commands.
It’s also no any reponse as following manualcommand on ubuntu.
sudo echo -en “AT\r\n” > /dev/ttyUSB2;cat /dev/ttyUSB2
Maybe the ttyUSB2 and ttyUSB3 is not the AT port.
I notice that there is another USB serial device connect with the Ubuntu.
I connected only a CP2102 (USB to UART). I found ttyUSB, including ttyUSB0 to ttyUSB3. I tested all of them in minicom with the serial device set to /dev/ttyUSB0 through /dev/ttyUSB3. However, when I input “AT,” there was no response to the AT commands.
Please remove the cp210 and connect with the RM520N.
The RM520N is not connected, why you try to send AT command?
The purpose of using AT commands is to query and debug information related to the modem. The CP2102 (USB to UART) cable is used to connect via PuTTY for this purpose.
https://forums.quectel.com/uploads/default/original/2X/6/60d2b84d0d7ede8f346e9778b6ae54b4e73a5630.png
But we can see it before but we cannot see it now
Please check
dmesg | grep -i usb
log.txt (18.6 KB)
The purpose of using AT commands is to query and troubleshoot modem-related information. Is there an easy way to use AT commands without connecting via PuTTY, and can they be executed directly on the DUT?
Thanks
For example
Line 157: [ 16.191827] usb 2-4: GSM modem (1-port) converter now attached to ttyUSB0
Line 159: [ 16.201027] usb 2-4: GSM modem (1-port) converter now attached to ttyUSB1
Line 164: [ 16.211475] usb 1-2.2: FTDI USB Serial Device converter now attached to ttyUSB3
Line 167: [ 16.211929] usb 1-2.2: FTDI USB Serial Device converter now attached to ttyUSB4
Line 171: [ 16.212537] usb 1-2.2: FTDI USB Serial Device converter now attached to ttyUSB5
Line 174: [ 16.212995] usb 1-2.2: FTDI USB Serial Device converter now attached to ttyUSB6
Line 175: [ 16.216908] usb 2-4: GSM modem (1-port) converter now attached to ttyUSB2
Line 176: [ 16.224125] usb 2-4: GSM modem (1-port) converter now attached to ttyUSB7
the ttyUSB2 and ttyUSB7 could work as AT port.
You could check that whether the ttyUSB2 is a Linux character device.
ls /dev/ttyUSB* -la
And on the other hand, please check wether there is any other proccess that already opened the ttyUSB2.
fuser /dev/ttyUSB2
lsof | grep ttyUSB