Em9191 - 5G support


we are trying to use a EM9191 (via the Sierra Wireless M.2 Developer Kit EM9/EM76 Series) connected to a Linux laptop. We found that the modem is detected using the qmi_wwan (although only using the MBIM mode and without being able to use the USB port for serial connection) and that we are able to connect them to 4G networks by using the last version of the libqmi library. However, the modem fails when trying to connect to 5G NSA o 5G SA networks. In some cases, we found that the qmicli client retrieves a 5G signal strength which seems to be totally wrong (-32768 dBm :sweat_smile:)

Did somebody have success in connecting this device to a 5G NSA or SA network? We are thinking that maybe we have an issue with the FW of the modem, but we saw that in the official web page there is not info about any FW relase.

Also, do you know how to activate the serial support in order to send AT commands. We tried to bind the device to the “option” module, but it didn’t work. Should we use the GobiNet driver?

Thank you!

Hi @miguel.catalan,

You can install this driver MBPL_Drivers_USB_R18_ENG1-src.tar.gz to detect AT port (at link: Mobile Broadband Package for Linux (SDK, Drivers, Documentation)). Then you can check via command: ls /dev/ttyUSB* and open AT port via command: sudo minicom -D /dev/ttyUSB*.
And can you check whether your network supports 5G NSA or SA?



Just to answer some of your questions.

  • Yes we have tested against 5G NSA and SA networks, both lab equipment and operators with various infrastruture vendors.
  • Re firmware we have a number of releases 1.07.13 is the currently approved release on AT&T and Verizon with 1.07.19 also being a good release. You will need to get hold of these firmware builds through your commercial channel i.e. who you bought the units through.
  • There are older builds and generically speaking they are good although I would obviously recommend you to use the approved ones.
  • On the driver from you need to use the open source drivers which are on the source. GobiSerial and GobiNet are now only applicable to older devices, we will be moving more and more over the the open source drivers and out MBPL package as time goes on.