Ever discovered your self with a bricked ExpressLRS receiver after a nasty firmware replace? Or are you unable to flash your RX utilizing FC Passthrough nor WiFi? That is the place an FTDI dongle comes into play. On this information, I’ll stroll you thru the method of flashing ExpressLRS receivers through UART utilizing an FTDI programmer, such because the Radiomaster USB UART Flasher.
Why Use FTDI for Firmware Updates?
Whereas the best strategies to replace firmware are through Betaflight Passthrough or Wi-Fi (which I’ve lined in a earlier tutorial), there are cases the place these strategies would possibly fail, reminiscent of a lack of connection. These points may end up in bricked receivers, the place the bootloader turns into corrupted.
An FTDI programmer, which permits flashing through UART, can come to the rescue. This methodology may also be helpful in the event you’re not utilizing a flight controller or don’t have entry to Wi-Fi. It’s a flexible resolution that works with all manufacturers of ELRS receivers, for each 2.4GHz and 900MHz, with out the necessity for specialised software program.
{Hardware} Requirement
For this activity, you’ll want a USB to serial programming device, generally referred to as an FTDI Programmer. Many producers provide devoted instruments for this goal, such because the Radiomaster USB UART Flasher, accessible right here:
Whereas BetaFPV additionally provides the same device, the ExpressLRS Restoration Dongle (https://oscarliang.com/product-9zim), I’ll be utilizing the Radiomaster mannequin on this demonstration. The steps, nonetheless, are related for each.
A generic FTDI programmer is a less expensive possibility (https://oscarliang.com/fpv-tools/#FTDI-Adapter), although it lacks the comfort of spring-loaded pins and different devoted harness that facilitate solder-free connections.
The FTDI programmer is easy to make use of. You’ll be utilizing 4 pins: RX, TX, VCC, and GND. VCC is 5V, GND is floor, and RX/TX are the information connection.
Step 1 – Plug in FTDI Dongle
Begin by opening the ExpressLRS Configurator and noting the accessible COM Port (COM port quantity might be completely different in your laptop).
After connecting the FTDI dongle to your laptop, choose the newly appeared COM port. If no new COM port seems, you could want to put in the cp2102usb driver.
Step 2 – Join Receiver to FTDI Dongle
To replace through FTDI, the receiver should be in boot mode.
This sometimes includes holding down the boot button on the receiver whereas connecting it to the FTDI Dongle (you’ll be able to launch the button as soon as the LED activates). Some receivers could require bridging two solder pads as a substitute of urgent a button (you’ll be able to take away the solder bridge after flashing).
Join the receiver to the FTDI Dongle utilizing the spring-loaded pins (whereas holding down the boot button). Right here’s the connection order to observe:
- VCC – 5V
- GND – GND
- TX – RX
- RX – TX
Ought to I exploit 5V or 3.3V? For many ExpressLRS receivers, the 5V setting is acceptable.
The Radiomaster UART Flasher additionally features a cable harness for receivers with out solder pads.
As soon as linked, the receiver ought to energy up with a stable LED, indicating it’s in boot mode and able to be flashed.
Step 3 – ExpressLRS Configurator
Proceed with the usual setup within the ExpressLRS Configurator. Select your firmware model, system class, and particular mannequin. Make sure the flash methodology is about to UART.
Configure the remainder in keeping with your preferences, and make sure the COM port of your FTDI programmer.
Step 4 – Begin the Replace
Click on on ‘Construct & Flash’ to provoke the replace. As soon as the method completes efficiently, you’ll be able to disconnect the receiver from the FTDI dongle.
Conclusion
Understanding easy methods to replace ExpressLRS receivers through FTDI is extremely helpful, notably when different approaches fail. This tutorial goals to offer a transparent, step-by-step information to effectively recuperate and improve your ELRS RX utilizing an FTDI programmer, such because the Radiomaster USB UART Flasher. This course of would possibly save your bricked RX from being discarded. Bear in mind, all the time double-check your connections and settings to make sure a profitable replace.
