What is “xa” Package?

6502 cross assembler
For more details: http://www.floodgap.com/retrotech/xa/

Installation

• Open Terminal by pressing command+space then type terminal and hit Enter key.
• Install homebrew first.

  ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" < /dev/null 2> /dev/null

• Install xa.

  brew install xa

Now, use xa!