This is a guide to show you how to update the internal ELRS TX module firmware in the Radiomaster Zorro radio.
Check out my review of the Radiomaster Zorro, it’s a great radio. This tutorial only applies to Zorro ELRS version.
Download ExpressLRS Configurator
If you haven’t already downloaded the latest ExpressLRS configurator, get it here and install it on your computer:
Open ExpressLRS configurator:
- In Releases, select the latest version.
- In Device category, select Radiomaster 2.4GHz
- In Device, select Radiomaster Zorro 2400 TX
- Flashing method, EdgeTXPassthrough
Choose your preferred Device options, if not sure what they mean, check out my ELRS tutorial here. Here’re a few important ones:
- Regulatory domains, choose ISM_2400
- Binding phrase
Flashing ELRS Firmware
Turn on the Zorro radio, and plug in the USB cable (to the top connector, NOT the bottom one). On the radio, you should be prompted 3 options, choose USB serial (debug).
Back to the ELRS configurator, hit Build and Flash.
If this is your first time, it can take a few minutes.
If you have trouble flashing via USB, you can also try flashing using WiFi:
- Turn on WiFi on the internal TX module in the ExpressLRS LUA Script
- In the ExpressLRS Configurator on your computer, build the firmware (just Build, NOT Build and Flash), this will save a firmware file on your computer
- Then upload the firmware file via the browser
- Here’s my detail instructions: https://oscarliang.com/setup-expresslrs-2-4ghz/#compile-and-flash-tx-firmware
Updating LUA Script
After successful flashing, hit the DOWNLOAD LUA SCRIPT button, and save the file somewhere.
Close the configurator and unplug USB cable.
Reconnect the radio’s USB cable, this time select USB Storage (SD). You should see two newly added external drives. Open the one with lots of folders.
Go to the \SCRIPTS\TOOLS folder, delete the old LUA scripts (with the same name as the one you just downloaded), there should be two files, .lua and .luac, delete both. Copy the downloaded file to the TOOLS folder.
Eject the external drive safely and unplug USB cable.
Verifying Firmware Update
In Model Setup, scroll down to Internal RF, and make sure Mode is set to CRSF.
Hold down the SYS button and go to TOOLS, find ExpressLRS. At the very bottom, you can see the current firmware version number (e.g. 2.3.0), make sure it’s the version you just flashed to confirm successful firmware update.