Testing on an NCM-MBIM composite modem.

Bjørn Mork bjorn at mork.no
Sat Jun 14 04:32:04 PDT 2014

I currently have two such modems:
Ericsson H5321gw and Sierra Wireless EM7345

That is, I don't know if the latter really is supported in NCM mode. It has an odd ff:ff:ff:ff:ff:ff mac address, and I haven't figured out how to make it connect in NCM mode. I can attach and connect to the network using standard at commands, but I am unable to activate the NCM data channel. At first I believed it just failed to send the expected notifications, but there is more than that missing.

And the fact that Lenovo provides a windows 7 MBIM driver and no NCM driver, together with the obviously nonfunctional mac address, makes me think that the NCM mode might just be something they left in the USB descriptors by accident.

The Ericsson modem works fine both as an MBIM and as an NCM device. It use the usual Ericsson mbm commands for NCM management, and is fully supported by MM in both modes.


On 14 June 2014 00:37:20 CEST, Prathmesh Prabhu Chromium <pprabhu at chromium.org> wrote:
>Hi list,
>Could you suggest some (supported?) MBIM-NCM composite modems that use
>suggested USB descriptor scheme in the MBIM spec, i.e., the
>Interface Class header has two alternate settings, and the
>Data Class has three alternate settings.
>ModemManager-devel mailing list
>ModemManager-devel at lists.freedesktop.org

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