Ever discovered your self with a bricked ExpressLRS receiver after a foul 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 by way of UART utilizing an FTDI programmer, such because the Radiomaster USB UART Flasher.
Why Use FTDI for Firmware Updates?
Whereas the simplest strategies to replace firmware are by way of Betaflight Passthrough or Wi-Fi (which I’ve lined in a earlier tutorial), there are cases the place these strategies may fail, akin to a lack of connection. These points can lead to bricked receivers, the place the bootloader turns into corrupted.
An FTDI programmer, which allows flashing by way of UART, can come to the rescue. This methodology can be helpful in case 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 software, generally often called an FTDI Programmer. Many producers supply devoted instruments for this objective, such because the Radiomaster USB UART Flasher, obtainable right here:
Whereas BetaFPV additionally presents an analogous software, the ExpressLRS Restoration Dongle (https://oscarliang.com/product-9zim), I’ll be utilizing the Radiomaster mannequin on this demonstration. The steps, nonetheless, are comparable for each.
A generic FTDI programmer is a less expensive choice (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 simple 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 obtainable COM Port (COM port quantity may be completely different in your pc).
After connecting the FTDI dongle to your pc, 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 by way of FTDI, the receiver have to be in boot mode.
This usually includes holding down the boot button on the receiver whereas connecting it to the FTDI Dongle (you possibly can launch the button as soon as the LED activates). Some receivers might require bridging two solder pads as an alternative of urgent a button (you possibly can 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 take advantage of 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, gadget class, and particular mannequin. Make sure the flash methodology is about to UART.
Configure the remaining in keeping with your preferences, and ensure 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 possibly can disconnect the receiver from the FTDI dongle.
Conclusion
Understanding tips on how to replace ExpressLRS receivers by way of FTDI is extremely helpful, notably when different approaches fail. This tutorial goals to supply a transparent, step-by-step information to effectively get well and improve your ELRS RX utilizing an FTDI programmer, such because the Radiomaster USB UART Flasher. This course of may save your bricked RX from being discarded. Bear in mind, at all times double-check your connections and settings to make sure a profitable replace.
