Read contribute guide: https://github.com/earlephilhower/arduino-pico/blob/master/docs/contrib.rst

Step 1: Clone arduino-pico.gi
    Make a fork project of https://github.com/earlephilhower/arduino-pico.git 
    $ git clone [fork]
    $ cd [fork]
    $ git submodule update --init
    $ cd pico-sdk
    $ git submodule update --init
    $ cd ../tools
    $ py -3 ./get.py

Step 2: Add new board:
    1. Add IDM2040 information to: package/package_pico_index.template.json
    2. Add IDM2040 board to: tools/makeboards.py
    3. Add IDM2040 pins header: variants/bridgetek_idm2040_43a/pins_arduino.h
    4. run: $ py -3 tools/makeboards.py
    5. Add README.md
    6. Add IDM2040 to github.com/Bridgetek/RP2040-BrtEve/blob/main/readme.md
    7. Create a new github repo, this contains:
        - examples
        - src
        - keywords.txt
        - library.properties
       Example: https://github.com/Bridgetek/RP2040-BrtEve

Step 3: Commit new board and generate release package:
    1. Run on window command promt:
        $ set X=3
        $ set Y=9
        $ set Z=2
        $ py -3 tools/makever.py --version %X%.%Y%.%Z%
        $ git add -A 
        $ git commit -a -m "Update a test version %X%.%Y%.%Z%"
        $ git push
        $ git tag %X%.%Y%.%Z%
        $ git push origin %X%.%Y%.%Z%

    2. go to github, publish the newly created release by git workflow, then download package_rp2040_index.json
    3. modify "url" inside package_rp2040_index.json
    4. commit package_rp2040_index.json

Step 4: Run with Arduino IDE:
    1. Goto Arduino IDE, select file->preference, add this to "Additional board managers"
        https://raw.githubusercontent.com/brtchip-tuannguyen/arduino-pico-fork/master/package_rp2040_index.json

    2. Goto Arduino IDE, select tool->board->board managers
        Search for "pico" text
        install the newly version just commited in step 3
        
    3. Goto Arduino IDE
        select tool->board->Raspberry->IDM1040
        Select tool->port ->COMP (pico)

    4. Goto Arduino IDE->file->example->Invader
    5. Goto Arduino IDE, press "Upload", after this, the Invader will be compile and run on IDm2040