Referfence manual and more information archived here:
http://retro.hansotten.nl/6502-sbc/lee-davison-web-site/enhanced-6502-basic/

You must have on your development system:

• VSCode. This has its own installer.
• A source install of this CC65.
• The following suite of tools for your specific OS.

$ sudo apt-get install cmake python3 pip git build-essential
$ pip install pyserial