# vim-syntax-asm_ca65
Vim syntax highlighting for the `ca65` assembler.

## Purpose

This repository provides `asm_ca65.vim`, a [Vim](http://www.vim.org/)
syntax-highlighting module for the
[`ca65`](http://cc65.github.io/doc/ca65.html) assembler.

`ca65` is a full-featured assembler for the [MOS
6502](https://en.wikipedia.org/wiki/MOS_Technology_6502) family of
microprocessors, which powered such historic platforms as the KIM I, Apple II,
Commodore 64, and Nintendo Entertainment System. It is a part of the popular
[`cc65`](https://github.com/cc65/cc65) suite of development tools for the 6502,
which also includes a C compiler, linker, object dumper, etc. `ca65` is
designed both for direct use by assembly programmers and as the compilation
target of the `cc65` C compiler. `ca65` is especially used by "homebrew"
communities for the [NES](http://nesdev.com), SNES, etc.

The stock Vim runtime distribution includes syntax modules for several dialects
of assembly, as well as a "generic" module (which is really for the GNU
Assembler), none of which works particularly well with 6502 assembly
conventions, and especially not with `ca65`'s many added features.

## Features

* Highlights 6502 instruction mnemonics as keywords, with special highlighting
  for "illegal" instructions, and error highlighting for unknown (typo)
  instructions.
* Highlights all valid `ca65` numeric and string literals, label
  definitions, and comments, with special highlighting for TODOs, FIXMEs, etc.
* Highlights all valid expression operators and control comands, with special
  treatment for various classes of commands, including `.fileopt`, segment
  names, includes, macro definitions, storage types, conditional assembly,
  linker control commands, structs, unions, procedures, pseudo-functions, some
  built-in macros, console output commands (`.out`, `.warn`, .etc.), and
  assembler behavior switches.

### Examples (screenshots)

#### Solarized colorscheme
![](https://raw.githubusercontent.com/maxbane/vim-syntax-asm_ca65/screenshots/sshot0-solarized.png)

![](https://raw.githubusercontent.com/maxbane/vim-syntax-asm_ca65/screenshots/sshot1-solarized.png)

#### Elflord colorscheme
![](https://raw.githubusercontent.com/maxbane/vim-syntax-asm_ca65/screenshots/sshot0-elflord.png)

![](https://raw.githubusercontent.com/maxbane/vim-syntax-asm_ca65/screenshots/sshot1-elflord.png)

## Limitations

* `asm_ca65.vim` currently has no awareness of, or support for, assembler
  options that change the rules of valid labels, identifiers, and literals from
  their defaults, for example the following `.feature` options and related
  command-line switches to `ca65`.
  * `.feature at_in_identifiers`
  * `.feature dollar_in_identifiers`
  * `.feature labels_without_colons`
  * `.feature underline_in_numbers`

## Installation

Simply place `asm_ca65.vim` in your `~/.vim/syntax/` directory, or, if you use
Pathogen, clone this repository under `~/.vim/bundle/`.

## Usage

`:set syntax=asm_ca65` or create an `autocmd`, as with any syntax module.