These instructions are a modified version of from: https://www.zigbee2mqtt.io/information/flashing_the_cc2531.html
### Firmware
You first need to download the firmware that should be flashed to the stick. There are multiple sources where firmware can be downloaded at:
* Download firmware from GitHub [CC2531_DEFAULT_xxxxxxx.zip](https://github.com/Koenkk/Z-Stack-firmware/raw/master/coordinator/Z-Stack_Home_1.2/bin/default/CC2531_DEFAULT_20201127.zip) (If link is dead try latest version [here](https://github.com/Koenkk/Z-Stack-firmware/tree/master/coordinator/Z-Stack_Home_1.2/bin/default)).
More information about available firmware can be found [here](https://github.com/Koenkk/Z-Stack-firmware/tree/master/coordinator).
* Download official Z-STACK software (We do not actually need the software just the firmware binary that is included in the installation) from https://www.ti.com/tool/Z-STACK (You will need to create an account to download)
* If the light on the CC debugger is RED press set reset button on the CC debugger. The light on the CC debugger should now turn GREEN. If not use [CC debugger user guide](http://www.ti.com/lit/ug/swru197h/swru197h.pdf) to troubleshoot your problem.
3. Connect **BOTH** the CC2531 USB sniffer and the CC debugger to your PC using USB.
* If the light on the CC debugger is RED press set reset button on the CC debugger. The light on the CC debugger should now turn GREEN. If not use [CC debugger user guide](http://www.ti.com/lit/ug/swru197h/swru197h.pdf) to troubleshoot your problem.