xdt99-Mode For GNU Emacs

The Emacs library xdt99-mode provides three major modes for editing assembly, GPL and TI Extended BASIC programs. The assembly mode offers syntax highlighting and editing assistance, while the BASIC mode is currently limited to syntax highlighting.

The xdt99 library currently supports all instructions supported by xdt99 version 3.3.

Please note that stock Emacs uses relatively simple technology for analyzing source code, so the level of functionality that xdt99-mode can offer is limited. For advanced features such as semantic assistence please use the IntelliJ IDEA plugin instead.

Assembly Programs

Assembly support is provided by the asm99-mode major mode. To activate this mode, press M-x (i.e., press the meta key plus the X key) and enter asm99-mode at the prompt. Please refer to the installation section on how to automate this step.

asm99-mode highlights known TMS9900 and related mnemonics as well as various assembly constructs such as registers and strings. The look and feel of the highlighting can be customized using the Emacs font-lock faces.

Assembly program

Please note that library, unlike the IDEA plugin, cannot perform syntax checks.

The asm99-goto-def command will jump to the location of the label that the cursor is currently positioned on.

Goto symbol definition

The asm99-show-def command will show the label definition in the mini buffer. For easy navigation it is recommended to assign these commands to some shortcut keys of your choice (see below).

Show symbol definition

The comment-region command (typically bound to C-c ;) adds the xas99 comment character ; to a range of lines. Conversely, the uncomment-region command removes a single ; character from each line.

Two minor modes provide support for formatting assistance. The asm99-smart-tab-mode minor mode will

automatically indent the current line based on the left-most character or word, and
advance the cursor to the next tab stop position, i.e., label, mnemonic, argument, or comment field,

whenever the user hits the Tab key. You may edit the Emacs variable tab-stop-list to adjust the tab stop positions to your liking. If electric-indent-mode mode is active, pressing Return will also indent the line just entered.

The asm99-smart-backspace-mode minor mode will move the cursor back to the previous tab stop if there is only whitespace between the cursor and the tab stop. In other words, the Backspace key acts as the inverse of the Tab key.

Both minor modes are active for asm99-mode by default but may be toggled by M-x asm99-smart-tab-mode or M-x asm99-smart-backspace-mode, respectively.

GPL Programs

GPL support is provided by the gpl99-mode major mode.

The GPL mode gpl99-mode is very similar to the Assembly mode and use the corresponding functions xga99-goto-def, xga99-show-def.

GPL program

Because of the large similarities between GPL and assembly, gpl99-mode reuses the settings for Smart Tab and Smart Backspace.

TI BASIC and TI Extended BASIC Programs

TI (Extended) BASIC support is provided by the basic99-mode major mode. To activate this mode, press M-x and enter basic99-mode. Please refer to the installation section on how to automate this step.

basic99-mode highlights known TI Extended BASIC keywords and various BASIC constructs such as line numbers and strings. The look and feel of the highlighting can be customized using the Emacs font-lock faces.

TI Extended BASIC

basic99-mode also supports BASIC programs with labels instead of line numbers.

TI Extended BASIC with Labels

There is currently no additional editor assistance for TI Extended BASIC beyond the built-in Emacs functionality. It is also not possible to restrict the basic99-mode to TI BASIC only.

Installation

Emacs is configured by creating a .emacs file in your home directory. For Windows-specific information about the home directory, please refer to the relevant [GNU FAQ item][5].

Extensions are generally placed into the Emacs site-lisp directory or into your local .emacs.d directory. When using a non-standard directory, you need to add its location to your library path in your .emacs config file, e.g.,

(add-to-list 'load-path "~/.emacs.d/")

To activate the xdt99 extension for Emacs, add

(autoload 'asm99-mode "xdt99-mode" "TMS9900 Assembly Mode" t)
(autoload 'gpl99-mode "xdt99-mode" "GPL Mode" t)
(autoload 'basic99-mode "xdt99-mode" "TI Extended BASIC Mode" t)

to your .emacs file.

The xdt99 Emacs library has been tested with Emacs 24, but newer or reasonably older versions of Emacs should also work.

Customization

You can associate arbitrary file extensions to the major modes provided by xdt99:

(setq auto-mode-alist
  (append '(("\\.a99$" . asm99-mode)    ; .a99 -> assembly
            ("\\.asm$" . asm99-mode)    ; .asm -> assembly
            ("\\.gpl$" . gpl99-mode)    ; .gpl -> GPL
            ("\\.b99$" . basic99-mode)  ; .b99 -> TI BASIC
            ("\\.bas$" . basic99-mode)  ; .bas -> TI BASIC
            ("\\.xb$" . basic99-mode)   ; .xb  -> TI BASIC
           ) auto-mode-alist))

Alternatively you can use M-x asm99-mode, M-x gpl99-mode, and M-x basic99-mode to activate or deactivate each mode for the active buffer.

It is recommended to use electric-indent-mode with smart tabs, but it may not be enabled by default. To use electric-indent-mode, add

(electric-indent-mode 1)

To permanently disable the smart tab and/or smart backspace minor modes, add one or both of these lines to your .emacs file:

(asm99-smart-tab-mode 0)
(asm99-smart-backspace-mode 0)

You can always use M-x asm99-smart-tab-mode and M-x asm99-smart-backspace-mode to activate or deactivate each minor mode for the active buffer.

For easy navigation you may assign label navigation to some convenient key shortcut:

(global-set-key [f3] 'asm99-goto-def)
(global-set-key [S-f3] 'asm99-show-def)

These lines assign functions asm99-goto-def and asm-show-def to the F3 and Shift-F3 keys, respectively.