[elral]

Description of changes

When connecting to AVR boards with DTR enabled, these boards get resettet on connect. After resetting the boards respond at least with 17,OK; (not processed from the connector). Other board types which are used for community devices might also respond with additional messages which could lead to an unrecognized board or set them into bootlaoder mode (could happen for some ESP32 boards).

This PR disables setting DTR line on connect for all boards except for ProMicro and Pico which requires setting the DTR line.

See also PR #2870 and issue #2849 in the connector repo.

[github-actions]

Board and firmware folder for this pull request:
Mobiflight-Firmware.zip

[ccrawford]

Thank you! Community device authors will be pleased.

[Copilot]

Pull request overview

This PR updates board definition files to prevent unintended device resets (and subsequent unexpected startup messages) by disabling the DTR line on initial connect for boards where it is not required, while keeping DTR behavior for the Pro Micro unchanged.

Changes:

• Set Connection.DtrEnable to false for Arduino Uno, Nano, and Mega board definitions.
• Set Connection.DtrEnable to false for Raspberry Pi Pico board definition.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
_Boards/arduino_uno.board.json	Disables DTR on connect to avoid auto-reset/bootloader side effects.
_Boards/arduino_nano.board.json	Disables DTR on connect to avoid auto-reset/bootloader side effects.
_Boards/arduino_mega.board.json	Disables DTR on connect to avoid auto-reset/bootloader side effects.
_Boards/raspberrypi_pico.board.json	Disables DTR on connect to avoid unintended behavior on connect.

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[github-actions]

Board and firmware folder for this pull request:
Mobiflight-Firmware.zip

[elral]

I will close this PR as the plain Arduino Mega with 32u4 chip on board as USB-seriell converter needs the DTR line enabled to work.
If we want to disable the DTR line for CH340 chips, we have to set up two different board.json files and figure out all VID/PID's for CH340 chip.