I'm trying to use a Huawei E3276S dongle with a GL-MT300N V2 router.  The connection to the network was straightforward enough and it's working well.

 

What I'm trying to do is work out how to send USSD codes through the router interface to check balance and buy one off internet packages.

 

The limited research I've done suggests AT+CUSD=1, "#123",15 should work but it errors out  with +CM# ERROR: UNKOWN

 

Any ideas or suggestions of another way to do what I want with swapping the SIM between the dongle and a phone?

 

Thanks

 

 

 

 

 

Seems dongle/SIM connects to True mobile?

You want to send "#123"?

Isn't it "#123#"?

is there an extra space between

1,

and

"#123

?

 

try the test command (show phone number):

AT+CUSD=1,"99",15

 

 

9 minutes ago, KhunBENQ said:

 

Seems dongle/SIM connects to True mobile?

You want to send "#123"?

Isn't it "#123#"?

Yes  I'm trying to use True.

 

That was just a typo on here.  I was sending the correct code when I tried. 

6 minutes ago, fdsa said:

is there an extra space between

1,

and

"#123

?

 

try the test command (show phone number):

AT+CUSD=1,"99",15

 

 

Sending that command returns "OK" without anything else.

5 minutes ago, JaiMaai said:

Sending that command returns "OK" without anything else.

wait for several seconds, OK is a confirmation of receiving the command and after few seconds it shows the phone number.

 

# socat - /dev/ttyUSB2,b115200,crnl
AT

OK
AT+CUSD=1,"99",15

OK

+CUSD: 0,"MSISDN:66952012345",15   <<<===  shown after few seconds

AT+CUSD=1,"#123",15

OK   <<<<==== and nothing else happens 
AT

OK
AT+CUSD=1,"#123#",15    <<<=== note the second # after 123

OK

+CUSD: 0,"TrueMove-H credit is 16.79 Bt, you can use service until 26/10/2021",15  <<<=== shown after a few seconds

 

 

I think part of the problem may be that the router interface is not a fully-fledged terminal and just allows basic input.

 

I'll try and find a way of sending the commands another way,

yea I think that's the problem. You should connect to router's terminal via SSH and then connect to modem from the router.

If you use Mac or Linux the SSH client is preinstalled, if you use Windows then you need to download third party software such as Putty: https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html