USB port falling off shouldn’t be unusual in flight controllers. In case your FC has a damaged USB port, can’t connect with Betaflight (or INAV Configurator) or flash firmware, listed here are some fixes you possibly can try to avoid wasting your FC.
Earlier than you start, verify should you can solder the USB port again on although it’s often not a simple soldering job. In my expertise, in case your USB port broke off, chances are high the tiny solder pads are most likely ripped and irreparable, however it’s value checking, flight controllers are costly nowadays!
Get some spare USB ports right here:
Connecting FC to Laptop by way of FTDI Adapter
In case you simply wish to join your FC to Betaflight Configurator (or INAV configurator), all you want is only a FTDI adapter (aka serial converter).
Purchase an FTDI adapter right here:
For FPV drone builders, it’s a useful gizmo to have round, I extremely suggest getting one. It’s also possible to use an Arduino board loaded with customized code (be at liberty to google it I received’t go into particulars right here), however it’s much more difficult than utilizing a $3 plug-and-play FTDI adapter.
Relying on the kind of USB connection your flight controller has (i.e. CP2102 or VCP), further steps may be mandatory which I’ll clarify on this tutorial. Nearly all fashionable FC makes use of VCP connection nowadays, just some very previous FC use CP2102, in case you are undecided, this submit explains easy methods to determine which one you could have.
FC with VCP
In case you purchased your FC in the previous couple of years, it most likely makes use of VCP connection. It’s not as simple as CP2102 as a result of {hardware} UART’s are usually not mandatory enabled for USB connection by default. The excellent news is, it’s fairly frequent that flight controllers are shipped with UART1 enabled for MSP (it permits USB connection), so you possibly can strive connecting your FTDI adapter to UART1 first, and see should you can connect with the Configurator.
Strive different UART if that didn’t work, in case you are fortunate one of many UART might need MSP enabled.
Make sure that nothing else is linked to that UART, however the FTDI adapter.
See this instance under, “Configuration/MSP” is enabled on UART1, this lets you use the FTDI adapter to attach it to Betaflight Configurator.
If not one of the UART’s have MSP enabled, that is going to get difficult:
- You’ll have to flash your flight controller with a “rescue” firmware that has MSP enabled on UART1 (with Erase choice enabled). However doing this, you’ll lose the present FC configuration should you didn’t beforehand backup your settings.
- And you’ll’t flash FC firmware utilizing the FTDI adapter, as a result of it must be in DFU mode. You will want a STLink Device that means that you can add a firmware file (.hex) to the processor utilizing the STM32 ST-Hyperlink Utility.
- Purchase the ST Hyperlink V2 Device right here: Amazon | AliExpress
- Obtain STM32 ST-LINK utility: https://www.st.com/en/development-tools/stsw-link004.html
So that you see, it’s not straightforward. Anyway should you determine to go forward, that is easy methods to do it.
Join FC to STLink Device to flash rescue firmware:
- 5V to 5V
- GND to GND
- SWCLK (clock) to SWC
- SWDIO (information) to SWD
Right here’s a superb educational tutorial about easy methods to use the STLink instrument (begins from 4:40): https://youtu.be/5VmhoyL6Z7Q?t=280
One of many major challenges with this methodology is discovering the SWC or SWD pads, they don’t seem to be all the time damaged out to solder pads on the FC. Examine if you will discover them on yours earlier than continuing, if current, they’re often tiny and close to the processor for debugging functions, typically not even labelled so that you might need to do a little bit of “trial and error”.
To be trustworthy most individuals would have given up at this stage and simply get a brand new flight controller. I feel scraping off the solder masks and expose the USB port information traces could be simpler should you don’t have already got the instruments readily available. Hold studying.
FC with CP2102 Chip
In case you purchased the FC earlier than 2020, chances are high USB connection is by way of the CP2102 chip:Â UART 1 is reserved for USB connection.
On this case, you could join the FTDI Adapter to UART1 (and solely UART1), join these 4 wires:
- TX to RX
- RX to TX
- 5V to 5V
- GND to GND
Make sure that nothing else however the FTDI adapter is linked to that UART.
Then join the FTDI adapter to your pc, it’s best to see a brand new COM port seem.
Typically, you shouldn’t want to fret about driver in case your pc is already working along with your flight controller, which suggests driver is already put in. But when driver is required, you will notice a warning signal icon on that COM port. You possibly can usually get the motive force file on the product web page of your FTDI adapter, or just google the kind of adapter you could have.
In Betaflight/INAV Configurator, choose this COM port and hit the Join button. That’s it.
Easy methods to Repair Broken USB Port
If FTDI adapter methodology fails, and you can not flash rescue firmware, you possibly can strive attaching a breakout board to the FC. The concept is to search out the D+ and D- pads within the USB port, and join them to a USB breakout board. You should utilize it similar to a traditional USB port.
You should buy some USB breakout boards right here, very good to have some spare:
If these D+ and D- pads on the FC are usually not ripped, you possibly can merely solder wires to these pads. Connections:
-
- D+ to D+
- D- to D-
- VBUS to any 5V on the FC
- GND to GND
Listed here are the pinout of a micro USB breakout board, flight controllers use the identical 5-pin connector has the identical pinout:
Right here’s the pinout of a USB-C port, there are usually 16 pins (two rows of 8-pin), D- and D+ are often the middle two pins on each high and backside row rotated 180-degree:
If these pads are ripped, you possibly can attempt to observe the copper traces and discover the place they go, often find yourself at a small capacitor which is comparatively straightforward to solder to. Right here’s an instance the place D- and D+ are on a Matek FC.
In case you can’t discover that, you possibly can scrap off the solder masks and expose the copper traces for D- and D+, and solder the wires to them. I exploit a small file for that.
If you’d like these wires to remain on the FC completely you undoubtedly wish to glue the cables and solder joints securely so that you don’t break these tremendous tiny solder joints.
Edit Historical past
- Might 2018 – article created
- Apr 2021 – Betaflight now presents USB Rescue firmware within the firmware flasher, you now not have to obtain it manually from google drive
- Feb 2023 – Added data about flashing FC with out USB port, diagrams of USB port pinout
- July 2026 – Up to date hyperlinks


