Different baud rate of EM250 on different modules


  1. I have 2 identical XbeePRO S2B modules in programmable variant, XBP24BZ7 firmware. The thing is, when I want to update the firmware by XCTU, after using freescale processor’s bootloader menu, I have to communicate with EM250 with different baud rates: one requires 115200, as it’s written in datasheet, and the other module works only with 9600. Dear forum, I ask you to comment this situation and give a piece of advice, if I can change the baud rate of EM250.
  2. The second thing, that I can’t understand. I use two XBIB usb boards, they are just the same. I can enter the freescale bootloader’s menu of one S2B module on both of them, and the other module allows me do it with the only board. What that can mean??

Hello Dimitry,

By default, S2Bs come with radio configured at 9600 bps; on the other hand, the Freescale processor configures the radio to 115200 bps and if you are using the latest version of the API, saves it to the radio flash. So, you should always be able to enter the bootloader at 115200 bps. You can change the baudrate in X-CTU Modem Configuration tab (command BD once you bypass the freescale microprocessor.

Regarding being able to enter bootloader only with one XBIB, that’s more strange, ensure that the RTS and CTS lines are reaching the module’s pin. Also, you can try to flash the example application “Serial Bypass”. Best regards,

Following article describes the steps to bypass the module, http://www.digi.com/support/kbase/kbaseresultdetl?id=3291