ttyUSB2 to run 3G and AT commands at the same time



ttyUSB2 port is used for both 3G/4G and AT commands. When we use 3G/4G, ttyUSB2 is locked and we can’t send AT commands to MC7455. Vice versa, when we can send AT command, we can not use 3G/4G.

Is there any solution to use both 3G/4G and AT commands at the same time for port ttyUSB2?

Can anyone help?

Thank you in advance.




No there is only a single AT command port, if you really want to use PPP to perform your connection then you have to live without AT commands.

The alternative is to use the network interface as per the attached.

1aec569af75a1ab07c66bf85086071fc482f614b.docx (347.1 KB)



Instruction to install GOBI net and serial

Thank you for your reply Matt,

I will look into your document and see if it will solve my problem.


Hi Matt,

Can’t we configure AT command on ttyUSB0 or ttyUSB1?

Best regards,


Hi Matt,

I think I have to install GOBI net and serial,

Do you know the instruction to install GOBI? Can you send me?



The process for building the drivers into a standard Linux system are in the embedded text files within the document. If you have to cross compile that’s a different matter and you need to look through the forums of your platform to figure that one out.




Hi Matt,

It happens to me that I can’t open the text files embedded within the word document.
Can you send me the link to all the text files?

Thank you,



See Instruction to install GOBI net and serial