How to send AT command to EC20 module to read some data if gsm port already acquired by pppd service

Dear All,
We are facing one issue where we can not send AT commands to read data from gsm uart port as gsm uart port is already squired by running ppp services.

now how can i read data from gsm uart port using AT commands without interrupting pppd services which are running.


Any update, Dear Quectel team ?

When using PPP the device would have entered data mode. You need to temporarily exit data mode and then issue your AT commands in command mode.

As specified in the AT commands manual:

The +++ character sequence causes the module to switch from data mode to AT command mode. It
allows inputting AT commands while maintaining the data connection with the remote device.

  1. To prevent the “+++” escape sequence from being misinterpreted as data, it should comply to following sequence:
  • Do not input any character within T1 time (1000ms) before inputting “+++”.
  • Input “+++” within 1000ms, and no other characters can be inputted during this time.
  • Do not input any character within T1 time (1000ms) after “+++” has been inputted.
  • Switch to command mode, otherwise return to step 1.
  1. To return from command mode back to data mode: Enter ATO
  • Another way to change to command mode is through DTR, refer to AT&D command for details.

Hi Shilesh_Babu

Could write the FW version you are using.
For QuecOpen, you can send AT command through /dev/smd7 or /dev/smd9.

@Puck-Q, this is my EC20 firmware version EC20CEFILGR06A03M1G

Hi Shilesh_Babu

please send AT command through /dev/ttyUSB2.
By default, /dev/ttyUSB3 - modem port is used in the Quectel-PPP script.

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