How to use multeplixing mode

Hello ,
i want to connect 2 device in the same UART , for me UART2 , i know that there is a solution with CMUX command .there is someone khnow how to do this.
Thank you.


I’d like to do the same using UART1 on a 663f firmware using OpenAT 4.27a. Is there an application note or other document that may help to get started?

Best Regards,

I almost got it… then Blue Screen… I decided not to use multiplexing at this time…

are you using a usb->serial adapter?

Hello ,
How you do this Jan?
Regards !

Almost :wink: I know it’s not working with serial adapter. But since I run this in a virtual machine I thought it might be OK to use the “Hardware” port of the virtual machine, which then uses a usb serial adapter on the host computer. I guess it’s not :frowning:

I had the hardware simulation working in other cases of direct hardware access… But just doesn’t seem to do the trick here…

I used the example command from the AT comands description in AT+CMUX section. I closed the port in the terminal program I typed it in. Then you have to be quick… within 30 second I ran the windows cmux driver with selection 115200 baud and COM1. When I was connected, I opened DLC 1. That also worked. But it was looking for a driver I couldn’t locate, and running the terminal program again, the blue screen appeared…

Does anyone have an idea, where to find a .inf file (or something like that to install a driver windows xp is looking for) for the device with name “Wavecom DLC 1”?

Best Regards,

isn’t it included on the sdk ‘cd’?
i think it’s in the ‘drivers’ directory.

I used the files of that directory to re-install the mux driver. But that didn’t help. It is showing the device in the Device Manager, but no COM port is assigned… The driver tells me something like port 11 is used, but a COM11 is not available… Again, that all could be due to my special configuration. I should try it with a real serial port, but right now, I have no such system to try it on…

Thanks for your help,

I can use tje CMUX mode only with the PC ?

I would think you could use it with any kind of hardware as long as there underlying protocol is implemented, which is defined by 3GPP TS 27.010. (to implement yourself this could mean days or weeks of work… but it should be doable;-)

Thank for your answer and Good Luck !