AT+WDM - undocumented?

DevStudio 1.2.0 connected to Fastrack XTend with 7.4.0.a firmware.

Target Status & Configuration gives 1 warning:

What is AT+WDM :question:

It is not mentioned in the AT Commands Interface Guide for Firmware 7.44 (nor any earlier version)

I presume it must be to do with the new “Development mode” - for which I’d have to update the XTend firmware ?

Note that no answer” is not correct: the XTend does answer - with “ERROR”

You’re right.
This command allows a user to lock a port into the development mode.
This mode is used by Developer Studio to get traces from the device for debug. It is persistent to the resets.

Therefore it needs to be documented - so that a user can find how to get a module out of Development mode when it’s “accidentally” been left in development mode!

See: viewtopic.php?f=108&t=5156&p=22613#p22613

A quick preview of what will be documented in a future Firmware release:


Resets the development mode persistence (the persisted port will return to production mode after a target reset)


Asks for development mode to be persisted on the current port (the current port will stay in development mode even after a target reset)


Just a query command to retrieve the current port ID


A query command to retrieve the development mode persistence state (0/1), and the port ID on which the persistence has been configured.



Just to clarify a few points:

Can be issued on any port - doesn’t have to be the port currently in Development mode

ie, the port on which the command was issued - not (necessarily) the port that’s in Development mode.

The port ID has the same values as used by AT+WMFM; viz,
1 = UART1;
2 = UART2;
3 = USB.

The response is:

AT+WDM: <port-id>,<state>



Actually, I just made the check, and the response is +WDM: ,, but the behavior is quite strange… is always 1, and is really the “persisted dev mode” port ID, but in addition it will be set to 0 if no port is configured in this mode (default state).
I’m dealing with the FW team to see if they plan to change this behavior.

Thanks for the clarifications!


Since there are already units in the field with this behaviour, I think it would probably be too confusing to change it now.

IMO, best to leave it as-is, but ensure that it is clearly documented.

That’s also our opinion: too late to change it now :wink:

It is now documented in the 7.46 AT Commands Guide