XBee S2 AT Command Mode

Hello All,

I have a Series 2 OEM module plugged into an old MaxStream USB development board for the series 1 modules.

The S2 OEM module originally came with the “Router/End Device AT” firmware loaded. I used X-CTU to load the “Coordinator AT” v1002 firmware. The firmware uploaded succesfully.

After the firmware update, it seems that I can no longer stay in command mode. If I enter “+++” using the 1sec guard times, I DO get the “OK” prompt, but then the module no longer responds to any commands. If I wait the specified guard time and enter “+++” again, I DO get the “OK” prompt.

Furthermore, reading and writing firmware with X-CTU fails. It always returns this error on writing:
Getting modem type…OK
Programming modem…Lost communication with modem
Write Parameters…Failed

If I put a S2 module that I haven’t programmed into the same dev board, I can enter command mode and change parameters without any problems. Also, X-CTU is able to read the firmware and paramters.

Is anyone aware of any problems related to using one of the old dev boards with the new modules?

Can an offer any tips to get this issue resolved?

Thank you for any help!

I’m using Series 2 modules with Series 1 dev kit boards (serial and USB).

I did have some difficulty initially, which was cured when I installed the latest version of X-CTU downloaded from MaxStream’s website.

I am using the Frame API normally, but tried v1020 as a test and had no problems, so I would make sure your X-CTU is up-to-date (if you haven’t already).


Thank you all for your suggestions.

It seems that the firmware that I uploaded was corrupt. Performing a “Restore” and then a “Write” from within X-CTU corrected the problem.

Thank you again!

You can find the latest X-CTU here:

Just select the operating system you’re running this on from the selector.