Huawei E3131 and the ignored at^ndisdup command

[Bjørn Mork]

Aleksander Morgado <aleksander at lanedo.com> writes:

> According to Huawei, the only modems supporting NDISDUP in a Linux-based
> system are those exposing a standard ECM/NCM interface, i.e. with the
> following setup:
>  * bInterfaceClass=02
>  * bInterfaceSubclass=06
>  * bInterfaceProtocol=00
> or
>  * bInterfaceClass=02
>  * bInterfaceSubclass=0d
>  * bInterfaceProtocol=00
>
> In these modems, dialling is done through NDISDUP in the AT (PCUI) port.

I didn't even know they had any of those.  Have only seen the
substandard ones using something like 02/06/ff etc.

> Other modems exposing a wwan interface but without those
> class/subclass/protocol values are supposed to support NDISDUP through
> the NCM port with endpoint 0, but that is unsupported for now.

Yes, that is something we definitely should work out how to do.  Given
that these things are made to work with Windows, maybe the protocol is
as "simple" as RNDIS?

> There are
> also newer Huawei modems labelled as 'hi-link' (like the E303), which
> are supposedly auto-configured, but I haven't played with these yet. So
> for now, NDISDUP is used in those modems that we know for sure it is
> supported.
>
> In short, having the NDISDUP command supported by the AT interpreter in
> the modem doesn't mean it will actually do anything with it.

OK.  I guess I know that.  At least we know very well that it doesn't
necessarily do anything useful with it, even if it does something...


Bjørn