Problems with AT commands over USB



i’ve written an application which communicate with an Embedded Software in a Fastrack Xtend over the RS232 Port. The Application sends AT Commands, and the Fastrack Xtends answer with AT commands. It works very well. Now I tried to use the USB Port for the same application. The connection works but there are problems with the incomming data.

For example:
-the PC application send the command: “at+show” to the embedded Software

  • now the embedded software have to answer, with a lot of at commands:
    “at+version = 2”
    “at+date = 27.07.10” …
    but there comes no data, only when I send after the “at+show” command the at command “at”, then the USB Port on the PC receives first the “OK” answer and then the whole data (answer of the “at+show” command.

I hope there is someone who can help me.


I guess you are using ADL_AT_UNS macro for sending out response to the terminal. Because of this, the response is getting stored in the buffer and is displayed only when a terminal response is send on this port.
Instead,try using ADL_AT_RSP for the same.
Hope it helps.