MMBasic Syntax for Vim

Vim syntax highlighting and filetype plugin for MMBasic (PicoMite).

Features

✨ Complete Syntax Highlighting

• All MMBasic keywords, functions, and commands
• Control structures (IF, FOR, WHILE, SELECT CASE, etc.)
• Hardware commands (SETPIN, PWM, I2C, SPI, etc.)
• Graphics commands (PIXEL, LINE, CIRCLE, TEXT, etc.)
• WiFi/Network commands for WebMite
• Comments, strings, numbers (decimal, hex, binary, octal)
• Pin names (GP0-GP47)

🎨 Smart Editing Features

• Automatic indentation
• Code folding for SUB/FUNCTION blocks
• Matchit support for block structures
• Useful abbreviations (pr→PRINT, inp→INPUT, etc.)
• Case-insensitive keyword matching

📚 Based on Official Documentation

• Synchronized with PicoMite User Manual V6.02.00
• Supports all Raspberry Pi Pico variants (RP2040, RP2350, RP2350B)
• Includes WebMite WiFi commands

Installation

Manual Installation

Copy the files to your Vim directory:

Unix/Linux/Mac:

mkdir -p ~/.vim/{syntax,ftdetect,ftplugin,doc}
cp syntax/mmbasic.vim ~/.vim/syntax/
cp ftdetect/mmbasic.vim ~/.vim/ftdetect/
cp ftplugin/mmbasic.vim ~/.vim/ftplugin/
cp doc/mmbasic.txt ~/.vim/doc/

# Generate help tags
vim -c 'helptags ~/.vim/doc' -c quit

Windows:

mkdir %USERPROFILE%\vimfiles\syntax
mkdir %USERPROFILE%\vimfiles\ftdetect
mkdir %USERPROFILE%\vimfiles\ftplugin
mkdir %USERPROFILE%\vimfiles\doc

copy syntax\mmbasic.vim %USERPROFILE%\vimfiles\syntax\
copy ftdetect\mmbasic.vim %USERPROFILE%\vimfiles\ftdetect\
copy ftplugin\mmbasic.vim %USERPROFILE%\vimfiles\ftplugin\
copy doc\mmbasic.txt %USERPROFILE%\vimfiles\doc\

vim -c "helptags ~\vimfiles\doc" -c quit

Using a Plugin Manager

Vim-Plug:

Plug 'path/to/mmbasic-vim'

Vundle:

Plugin 'path/to/mmbasic-vim'

Pathogen:

cd ~/.vim/bundle
git clone path/to/mmbasic-vim

Usage

The plugin automatically activates for files with .bas or .mmb extensions.

Syntax Highlighting

Open any MMBasic file:

vim myprogram.bas

Keywords will be highlighted automatically!

Code Folding

Fold SUB and FUNCTION blocks:

:set foldmethod=syntax
zc    " Close fold
zo    " Open fold
za    " Toggle fold

Matchit Support

Jump between matching keywords:

%     " Jump between IF/ENDIF, FOR/NEXT, etc.

Abbreviations

In insert mode:

pr<space>   → PRINT
inp<space>  → INPUT
fn<space>   → FUNCTION
sb<space>   → SUB

Settings

The plugin sets these defaults:

• tabstop=2 - Tab width
• shiftwidth=2 - Indent width
• expandtab - Use spaces instead of tabs
• autoindent - Auto-indent new lines
• smartindent - Smart indentation

To override in your .vimrc:

autocmd FileType mmbasic setlocal tabstop=4 shiftwidth=4

Example

' MMBasic Example - LED Blink
OPTION EXPLICIT

CONST LED_PIN = GP21
CONST DELAY = 500

SUB Blink(times AS INTEGER)
  LOCAL i AS INTEGER
  FOR i = 1 TO times
    PIN(LED_PIN) = 1
    PAUSE DELAY
    PIN(LED_PIN) = 0
    PAUSE DELAY
  NEXT i
END SUB

' Main program
SETPIN LED_PIN, DOUT
Blink(10)
PRINT "Done!"

Supported Syntax

Control Flow

IF condition THEN
  ' statements
ELSEIF condition THEN
  ' statements  
ELSE
  ' statements
END IF

FOR i = 1 TO 10 STEP 2
  ' statements
NEXT i

DO WHILE condition
  ' statements
LOOP

SELECT CASE variable
  CASE 1
    ' statements
  CASE 2 TO 5
    ' statements
  CASE ELSE
    ' statements
END SELECT

Hardware Control

' Pin configuration
SETPIN GP21, DOUT
SETPIN GP26, AIN
SETPIN GP0, I2C SDA
SETPIN GP1, I2C SCL

' Digital I/O
PIN(GP21) = 1           ' Set high
x = PIN(GP2)            ' Read pin

' Analog input
voltage = PIN(GP26) * 3.3 / 4095

' PWM output
PWM GP5, 1000, 50       ' 1kHz, 50% duty

' I2C communication
I2C OPEN 100, 1000
I2C WRITE &H48, 0, 1, &H01
I2C CLOSE

Graphics

CLS                              ' Clear screen
COLOUR 255, 0, 0                ' Red
BOX 10, 10, 100, 100            ' Draw box
CIRCLE 160, 120, 50             ' Draw circle
TEXT 10, 200, "Hello!", "LT", 2 ' Display text

Help

View the full documentation in Vim:

:help mmbasic

Color Schemes

The syntax file uses standard Vim highlight groups:

• Statement - Keywords (IF, FOR, PRINT, etc.)
• Function - Built-in functions (SIN, COS, LEN, etc.)
• Type - Data types (INTEGER, FLOAT, STRING)
• Operator - Operators (AND, OR, NOT, MOD, etc.)
• Comment - Comments (' and REM)
• String - String literals
• Number - Numeric constants
• Constant - Pin names (GP0-GP47)

These work with any Vim color scheme!

Compatibility

Supports:

• Vim 7.0 and later
• Neovim
• All PicoMite firmware versions
• WebMite (WiFi versions)

File Extensions:

• .bas - BASIC files
• .mmb - MMBasic files

Documentation

For complete MMBasic reference:

• PicoMite Manual: http://geoffg.net/Downloads/picomite/PicoMite_User_Manual.pdf
• Official Site: http://geoffg.net/picomite.html
• Community: http://mmbasic.com
• Forum: http://www.thebackshed.com/forum/Microcontrollers

License

Same as Vim itself. See :help license in Vim.

Credits

• MMBasic: Geoff Graham & Peter Mather
• PicoMite: Peter Mather (matherp)
• Manual: Geoff Graham with community input
• Vim Plugin: Based on PicoMite User Manual V6.02.00

Contributing

Issues, suggestions, and improvements welcome!

Based on the official PicoMite User Manual V6.02.00 (February 11, 2026).

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Happy MMBasic coding in Vim! 🚀