How to Upgrade ELRS Receiver and RF Module Firmware

CoreWingAbout 4 minINAVINAVELRSExpressLRS固件升级WiFi接收机高频头Backpack

1. Principle

ELRS (ExpressLRS) system provides a convenient firmware upgrade method, allowing direct firmware upgrades for receivers and VTXs through WiFi connection. With this method, users do not need a computer or dedicated firmware upgrade tools (such as ELRS Configurator), and can complete firmware updates by connecting devices to a WiFi network and operating through the RC transmitter.

2. Equipment Preparation

1) Flight Controller: Any of the following flight controllers are suitable for this tutorial: SpeedyBee F405 WING APP / SpeedyBee F405 WING MINI / CoreWing F405 WING V2.
2) RC Transmitter: Using Radiomaster TX16S / Radiomaster Boxer as examples.
3) Receiver: Using SpeedyBee ELRS Nano 2.4G as an example.
4) VTX: Built-in ELRS module or external ELRS VTX.
5) Computer: Used to access web configuration for VTX or receiver parameters.

III. Specific Operations

※You can directly go to Step 4 to view the specific firmware upgrade operations.

3.1 Receiver and Transmitter Firmware Compatibility Rules:

3.x.x versions: Different minor versions are allowed (e.g., 3.1.1 can bind with 3.1.2).
2.x.x versions: The RC transmitter and receiver must be exactly the same version (e.g., 2.0.1 must match 2.0.1).

3.2 Check Transmitter Firmware Version

Power on the RC transmitter, navigate to MDL → SETUP page, and enable the built-in or external transmitter.

Color screen settings:
Black and white screen settings:

Navigate to the SYS→TOOLS page and enter the ExpressLRS script.

Color screen settings:
Black and white screen settings:

Check the transmitter firmware version.

Color screen settings:
Black and white screen settings:

3.3 Check Receiver Firmware Version

Insert the receiver into the flight controller and power the flight controller using a data cable.
After powering on the receiver, wait for 60 seconds or long press the BAT key for 5 seconds to enter WiFi mode. The receiver status light flashing rapidly indicates it has entered WiFi mode.
Turn on WiFi on your computer → connect to the ExpressLRS RX receiver WiFi, the default password is lowercase "expresslrs".
After connecting to WiFi, wait for 10 seconds and the browser will automatically open and navigate to the 10.0.0.1 page; if the browser doesn't open automatically, you can directly enter 10.0.0.1 in the browser address bar to access the receiver.
You can view the receiver firmware version at the top of the page.

3.3 Upgrade Receiver Firmware via WiFi

After powering on the receiver, wait for 60 seconds or long press the BAT key for 5 seconds to enter WiFi mode. The receiver status light flashing rapidly indicates it has entered WiFi flashing mode;
Turn on WiFi on your computer → connect to ExpressLRS RX → the default password is lowercase "expresslrs".
After connecting to WiFi, wait for 10 seconds and the browser will automatically open and navigate to the ExpressLRS webpage; if it doesn't open automatically, you can directly enter 10.0.0.1 in the browser address bar to access it.
Enter the UPDATE page, click "SELECT FIRMWARE FILE" to load the file. In the pop-up window, select the downloaded firmware archive, and the webpage will automatically start flashing the firmware.
Until the following pop-up appears on the webpage, indicating the receiver firmware has been successfully flashed.

3.4 Upgrade Transmitter Firmware via WiFi

Open the ExpressLRS webpage in your browser: https://expresslrs.github.io/web-flasher/

Click on "Transmitter".
On the "Hardware" page, select the firmware version → select the brand corresponding to your transmitter → select the band corresponding to your transmitter → select the type corresponding to your transmitter → click Next.
On the "options" page, select WiFi as the flashing method, keep other parameters default, and click NEXT.
On the "Flashing" page, click "DOWNLOAD" to get a local bin file.
Enter the system menu on the RC transmitter, go to the ELRS script, select WiFi Connectivity → select WiFi Connectivity.
Select the transmitter WiFi and stay on the WiFi running page.
Turn on WiFi on your computer, connect to the transmitter WiFi, the password is lowercase: expresslrs.
After connecting to the transmitter WiFi, the browser will automatically redirect to the firmware flashing webpage; if there's no automatic redirect, manually enter 10.0.0.1 in the browser and press Enter to open the transmitter configuration page. On the configuration page, click to load firmware, select the downloaded bin firmware file, and flashing will start automatically.
Until the following pop-up appears on the webpage, indicating the transmitter firmware has been successfully flashed.

3.5 Upgrade Backpack Firmware

Open the ExpressLRS webpage: https://expresslrs.github.io/web-flasher/

On the ELRS webpage, click on "Transmitter Module".
On the "Hardware" page, select the firmware version → select the manufacturer corresponding to your transmitter → select the type corresponding to your transmitter → click Next. (Select according to your transmitter type, firmware requires version 1.5.0 or higher), it is recommended to select firmware version 1.5.1.
On the "options" page, select "WiFi" or "Local Download" as the flashing method, keep other parameters default, click NEXT.
On the "Flashing" page, click "DOWNLOAD". (It's an archive file, no need to extract)
Enter the system menu on the RC transmitter, go to the ELRS script, and select "WiFi Connectivity".
Select the transmitter "Backpack WiFi" and turn on WiFi.
Enter the WiFi running page, wait for 5 seconds and it will automatically exit this page, which is normal. Do not move the RC transmitter, WiFi is running.
Turn on WiFi on your computer, connect to the transmitter "Backpack WiFi", the password is lowercase: expresslrs.
After successfully connecting to WiFi, it will automatically jump to the firmware flashing webpage, or manually enter 10.0.0.1 in the browser. On the "BACKPACK" page, click Select File, select the downloaded firmware archive, and click "UPDATE" to start flashing.
Wait for the progress bar to complete, and when it displays Update succeeded, the flashing is successful.