AT command for query pdp context status on ZTE AC2791( MDM6600 chip set)

[Dan Williams]

On Wed, 2014-01-22 at 17:24 +0530, david preetham wrote:
> Hi,
> On modem interface i am able to connect the service provider using AT
> commands,
> I have requirement to know the status of PDP (connected or disconnected).
> Is their any AT commands to know the status? I don't have spec for AT
> commands.
> I tried to print AT commands supported AT&V no command helpful.
> 
> I tried AT+CREG, AT+CGACT,AT+CGATT this commands are not supported.
> Is their anyway to know the pdp context status

This is a CDMA device and thus it likely doesn't support most of the
3GPP AT commands.  Which also means it does not have PDP contexts at
all, since that's a 3GPP-only thing.  These modules support the IS-707
command set for CDMA devices, but that does not have any useful
commands.

Instead, you're stuck using QCDM/DIAG, which is a binary protocol that
older Qualcomm chips often support.  However, we haven't
reverse-engineered any of the QCDM commands that would indicate data
service status.

Since this device uses PPP though, couldn't you use the existence of a
PPP session on the host to determine whether or not the modem has an
active data connection?

Dan