The stable (51.03.07) branch of the pioarduino platform does not contain a board definition for the XIAO ESP32C6. However, this directory contains a proposed definition seeed_xiao_esp32c6.json which has been successfully tested with all the projects in the repository.
To use the boards/seeed_xiao_esp32c6.json definition in a PlatformIO project, add the following line in the project configuration file (platformio.ini): boards_dir = ../boards. Here is a typical example.
platformio]
src_dir = async_web_led
boards_dir = ../boards
[env:seeed_xiao_esp32c6]
platform = https://github.com/pioarduino/platform-espressif32/releases/download/51.03.07/platform-espressif32.zip
board = seeed_xiao_esp32c6
framework = arduino
...References: Custom Embedded Boards, boards_dir.
The development branch of the pioarduino platform contains the board definition since November 6, 2024 (Commit bdae53d . The first example project in this repository uses that branch. Here are the first few lines of its configuration file.
[platformio]
; Make the Arduino IDE happy (.INO file must be in a directory of the same name)
src_dir = pin_names
[env:seeed_xiao_esp32c6]
platform = https://github.com/pioarduino/platform-espressif32.git#develop
...In this project, the content of the ../board directory will be ignored.
Just came across lucaskatayama:feat/seeed_xiao_esp32c6.json dated 0ct 4th. That board definition looks to be exactly the same as seed_xiao_esp32c6.json in this directory but for the order in which elements are listed.
It's all a bit confusing. Lucas wanted to merge the board definition into platform-espressif32. According to valeros, [the ESP32-C6] requires Arduino core v3.0 which is not officially supported yet. (July 3). Two weeks later jason2866, announced the pioarduino fork writing [since] it is now clear that there will be no official support for Arduino core 3.0.x from Platformio team, [...] i decided to fork the needed repo(s) and build a community version to support core 3.0.x (starting with core 3.0.3). (The emphasis on "yet" and "now" is mine.) So Lucas' work will not be used and I preempted his ability to contribute his definition to the pioarduino team? My apologies to Lucas Katayama whose work I should have credited.
Also, many thanks to jason2866 for pioarduino, it works very well.