XBee bootloader

XBee devices use a modified version of Ember’s bootloader. This bootloader version supports a custom entry mechanism that uses module pins DIN (TH pin 4/SMT pin 4), DTR / SLEEP_RQ (TH pin 9/SMT pin 10), and RTS (TH pin 16/SMT pin 29).

To invoke the bootloader, do the following:

1. Set DTR/SLEEP_RQ low (TTL 0V) and RTS high.
2. Send a serial break to the DIN pin.
3. Set DTR/SLEEP_RQ and DIN to low (TTL 0V) and RTS should be high.
4. Terminate the serial break and send a carriage return at 115200 baud to the device.
5. If successful, the device sends the Ember bootloader menu out the DOUT pin at 115200 baud.
6. You can send commands to the bootloader at 115200 b/s.

Note Disable hardware flow control when entering and communicating with the Ember 357 bootloader.

All serial communications with the module use 8 data bits, no parity bit, and 1 stop bit.

You can update firmware on the XBee/XBee-PRO Zigbee RF Module serially. This is done by invoking the bootloader and transferring the firmware image using XMODEM.