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doc:recipes:at_commands

How To send AT commands to device

You need to connect device/modem to PC and access it with any COM terminal.

If you are not familiar with using COM terminal, download some graphical tool like: CuteCom or minicom.

Usually these settings work fine:

Device: /dev/ttyUSB0
Connection: 115200 @ 8-N-1
Line end: CR

Here is Example for Huawei E392 LTE/3G dongle.

Send: AT
OK

Send: AT^SETPORT=?
Recieve: 1:MODEM
Recieve: 2:PCUI 
Recieve: 3:DIAG
Recieve: 4:PCSC
Recieve: 5:GPS
Recieve: 6:GPS CONTROL
Recieve: 7:NDIS
Recieve: A:BLUE TOOTH
Recieve: B:FINGER PRINT
Recieve: D:MMS
Recieve: E:PC VOICE
Recieve: A1:CDROM
Recieve: A2:SD
Recieve: OK

Send: AT^SETPORT?
Recieve: A1,A2;1,2,3,A1,A2
Recieve: OK

Send: AT^SETPORT="A1;2,7,A2"
Recieve: OK

Send: AT^SETPORT?
Recieve: A1;2,7,A2
Recieve: OK

AT^SETPORT=? - Lists the Available interfaces and their numbers

AT^SETPORT? - Show current configuration

AT^SETPORT="A1;2,7" - Sets configuration.

Modem configuration is splitted into 2 parts: before ";" and after.

Once modem is plugged-In - it declares itself in first configuration (normally with at least: A1 - virtual CD drive with Drivers and application). If the drivers are installed - they see the modem and issue a special command to switch to "working" configuration - this is 2,7 interfaces in this example.

:!: Never turn Off PC interface (2:PCUI in this example)!!! Otherwise you'd not have ability to access modem with terminal and change the config.

You can add more interfaces to be active i.e. SD card:

AT^SETPORT="A1,A2;2,7,A2"

If you get ERROR, maybe the numerical mode is not sorted (16,2,7)→(2,7,16). If your device answers to set command with OK but AT^SETPORT? doesn't show your desired settings, you can try using space in between numerical modes(2,7) and alphabetical modes(A2) like this:

AT^SETPORT="A1,A2;2,7, A2"
or with multiple modes:
AT^SETPORT="A1,A2;2,7, A1,A2"

doc/recipes/at_commands.txt · Last modified: 2017/04/16 20:06 by Jalakas