Flywoo F745 FC could not be connected to BF after update to 4.5 RC4 or RC3

[woefe1985]

Describe the bug

I am using a Flywoo F745 FC. When I update to 4.5 RC3 or RC4 (With Bethaflight 10.10 RC4!), I can no longer connect to the FC.I did not tryed RC1 and 2. The update itself seems to be successful. I have tried directly by connecting the FC and then selecting "Update Firmware", and I have tried several times by booting in boot mode first. The error code in the dialogue box after the update is "Failed to open serial port". I have previously installed 4.4.3, which works without any connection problems. To reconnect to the FC, I have to boot in boot mode, otherwise the FC will not be recognised. Then I have to go back to 4.4.3. After that, everything works perfectly again.

To Reproduce

use Flywoo F745 FC. Update to 4.5RC4 or 4.5 RC3. After that try to connect fia "Connect" button.

Expected behavior

I can remember i had the same problem with 4.4 after some while it worked (Mybe in 4.4.1 or 4.4.2).

Support ID

No output could not connect

Flight controller

Flywoo F745

Other components

Flywoo Explorer LR4 with Cognex Vista.

How are the different components wired up (including port information)

original no changings

Add any other context about the problem that you think might be relevant here

No response

[pasyn]

I am having the same issue. Hexplorer with Flywoo745. Initially after the update to 4.5 RC4, I could not connect to DFU either. Desoldering the receiver from UART1 allowed me to connect to DFU and reinstall 4.4.3.

[haslinghuis]

Seems like DFU hijacking issue. Please open new issue when resistant on official release.

[mmedinasantacruz]

Seems like DFU hijacking issue. Please open new issue when resistant on official release.

Hello!! I hope you are well. I would like to inform you that this situation still occurs in: Flywoo F745, Flywoo F745 Nano and Flywoo F745 HEX [betaflight 4.5.1] :(. I had to go back to version 4.4.3. Best regards

[nerdCopter]

FC advertises 7 UARTS, maybe do not use UART1.

[haslinghuis]

• Does it help using defaults commands before trying to flash ? (Always remember to save a backup before you use this command)
• This is not something Betaflight can fix, as this is a design feature / flaw on STM32 MCU's
• Hijacking DFU is mentioned here: https://betaflight.com/docs/wiki/guides/current/DFU-Hijacking#what-is-dfu-hijacking
• More info: https://betaflight.com/docs/development/manufacturer/manufacturer-design-guidelines#322-select-appropriate-default-uarts-to-avoid-hijacking-usb-dfu