CRBasic Language Support Extension

This Visual Studio Code extension provides comprehensive language support for the CRBasic programming language, used for programming Campbell Scientific CR and GRANITE series data loggers. Features include syntax highlighting, IntelliSense, signature help, hover documentation, code navigation, diagnostics, quick fixes, and an instruction browser panel.

Supported Dataloggers

This extension provides model-specific support for the following Campbell Scientific dataloggers:

IntelliSense, hover documentation, the Instruction Panel, and documentation links are all filtered based on the selected datalogger model, so you only see what your hardware supports.

Installation

From the VS Code Marketplace

1. Open VS Code
2. Go to the Extensions view (Ctrl+Shift+X / Cmd+Shift+X)
3. Search for "CRBasic"
4. Click Install on CRBasic VSCode Support - Campbell Scientific, Inc.

From a VSIX File

1. Download the .vsix file
2. In VS Code, open the Command Palette (Ctrl+Shift+P / Cmd+Shift+P)
3. Run Extensions: Install from VSIX...
4. Select the downloaded .vsix file

Getting Started

1. Open or create a CRBasic file with any supported extension: .crb, .cr1x, .cr300, .cr6, .dld
2. Select your datalogger model via File > Preferences > Settings and search for crbasic.dataloggerModel (or let the extension auto-detect it from the first line of your file)
3. Start typing to see IntelliSense suggestions, or browse the Instruction Panel in the Activity Bar sidebar
4. Create a new program from a template via File > New File... > CRBasic Program

Features

Syntax Highlighting

Comprehensive syntax highlighting for all CRBasic keywords, instructions, operators, data types, and comments. Semantic highlighting provides distinct colors for public variables, private variables, constants, data tables, and functions based on their declarations.

IntelliSense & Code Completion

• Smart auto-completion for 500+ CRBasic instructions and keywords
• Model-specific filtering -- only instructions supported by your configured datalogger model are shown
• Context-aware suggestions (e.g., output processing instructions only appear inside DataTable blocks)
• Cross-file completions — variables and constants from Included files appear in suggestions
• Categorized completions with detailed documentation
• Snippet support with tab stops for quick code entry
• Parameter pick list completions — when typing inside a function call, valid parameter values (voltage ranges, thermocouple types, data types, etc.) are suggested from the official DEF files

Signature Help

Inline parameter hints for all CRBasic functions showing:

• Function signature with all parameters
• Parameter descriptions with pick list options and default values from the official DEF files (e.g., voltage ranges, thermocouple types, data types)
• Current parameter highlighting as you type

Hover Documentation

Hover over any CRBasic keyword or function to see:

• Function signature
• Detailed parameter information with valid options and defaults from the official DEF files
• Links to official Campbell Scientific documentation (model-specific)

Documentation links dynamically point to the correct datalogger's help site based on your configured model.

Code Navigation

Code Diagnostics

Real-time validation that checks for:

• Mismatched Begin/End pairs (BeginProg/EndProg, If/EndIf, For/Next, etc.)
• Mismatched preprocessor directives (#If/#EndIf)
• Unclosed code blocks
• Unexpected end statements
• Unused variables, constants, data tables, subroutines, and functions (shown as faded text) — cross-file aware via Include resolution
• Duplicate variable, constant, data table, and subroutine declarations
• Missing Include files (warns when the referenced file does not exist)
• Incorrect argument counts in built-in function calls (too many or too few arguments)
• Literal type mismatches in function arguments (e.g., string literal where numeric expected, literal value where variable reference required)

Quick Fixes

Automatic code actions to fix common issues:

• Add missing EndIf for If statements
• Add missing EndTable for DataTable blocks
• Add missing Next for For loops
• Add missing EndSub for subroutines
• Add missing #EndIf for preprocessor conditionals

Auto-Capitalize Keywords & Variable Name Matching

Automatically corrects the casing of CRBasic identifiers as you type:

• Keywords & instructions — all 500+ built-in instructions are corrected to their canonical PascalCase (e.g., beginprog → BeginProg, scan → Scan)
• Logical operators — and → AND, or → OR, not → NOT, xor → XOR, mod → MOD, imp → IMP, intdv → INTDV
• Data types — float → Float, long → Long, double → Double, boolean → Boolean, string → String
• Other keywords — as → As, true → True, false → False, nan → NAN
• Variable name matching — corrects variable, constant, data table, and subroutine names to match their original declaration casing
• Skips corrections inside string literals and comments
• Configurable via crbasic.enableAutoCaseCorrection

Document Formatting

Format your entire CRBasic program with proper indentation using Format Document (Shift+Alt+F). The formatter:

• Automatically indents all block structures (BeginProg, Scan, If/Else/EndIf, For/Next, Sub/EndSub, DataTable, Select Case, While/Wend, Do/Loop, and more)
• Handles preprocessor blocks (#If/#ElseIf/#Else/#EndIf)
• Correctly identifies single-line If x Then y statements (no false indentation)
• Corrects keyword and variable name casing (when crbasic.enableAutoCaseCorrection is enabled)
• Respects your editor's tab size and spaces/tabs preference
• Strips trailing whitespace while preserving blank lines
• Ignores keywords inside string literals

Compile Program (Windows Only)

Compile your CRBasic program using Campbell Scientific's official compiler directly from VS Code:

• Click the play button in the editor title bar, right-click and select CRBasic: Compile Program, use the Command Palette, or press Ctrl+F6
• The correct compiler is auto-selected based on the detected datalogger model
• Compiler errors and warnings appear as VS Code diagnostics with correct line numbers
• Full compiler output is shown in the CRBasic Compiler output channel
• The file is automatically saved before compiling
• Requires the Campbell Scientific compilers to be installed (included with LoggerNet or the standalone CRBasic Editor)
• Configure the compiler directory via crbasic.compilerDirectory if installed to a non-default location

Code Folding

Collapse and expand code blocks including:

• Scan / NextScan loops
• DataTable / EndTable blocks
• If / Then / EndIf conditionals
• For / Next loops
• Sub / EndSub subroutines
• SlowSequence / EndSequence blocks

Document Outline Panel

A color-coded tree view in the CRBasic sidebar that displays all declarations in your program grouped by kind with rich type metadata:

• Grouped by kind: Public Variables (blue), Dim Variables (gray), Constants (orange), Data Tables (teal), Subroutines & Functions (purple)
• Each variable shows its data type (Float, Long, Boolean, String, Double), array dimensions (e.g., Float(14)), and string length (e.g., String *200)
• Constants show their assigned value (e.g., = 10.0)
• Includes declarations from Included files, annotated with the source file name
• Click any declaration to navigate to its source line (opens external files automatically)
• Automatically refreshes as you edit
• Empty groups are hidden
• Symbol colors are customizable via workbench.colorCustomizations (see Configuration)

Data Tables Panel

A sidebar panel that shows the data output structure of your CRBasic program at a glance:

• Displays every DataTable block with its output interval and units
• Expand a table to see all output fields with their field name, processing type (Average, Sample, Totalize, Maximum, Minimum, StdDev, WindVector, etc.), and data type (FP2, IEEE4, etc.)
• Correctly handles WindVector multi-field output (2-4 fields based on OutputOpt)
• Respects FieldNames overrides that rename default field names
• Click any table or field to navigate to its source line
• Automatically refreshes as you edit

Instruction Help Panel

A sidebar panel that shows live documentation for the CRBasic instruction under your cursor:

• Automatically updates as you move your cursor to different instructions
• Shows the instruction signature, description, parameters (with types), and example code
• Pin button to lock the current instruction and stop cursor tracking
• Insert button to insert the instruction (with snippet tab stops) at the cursor position
• Wizard button to launch the Parameter Wizard for guided, step-by-step instruction building
• Links to the official Campbell Scientific documentation for the selected datalogger model
• Also updates when clicking an instruction in the Instructions panel above

Parameter Wizard

A webview panel for building CRBasic instruction calls with all parameters visible at once:

• Opens beside the editor showing every parameter in a form layout with numbered fields
• Parameters with known options show a dropdown with valid values from the official DEF files (voltage ranges, thermocouple types, data types, etc.) plus a text input for custom values
• Parameters expecting variables show declared variables from your program (Public, Dim, Const, and Include'd file symbols) in the dropdown
• Parameters expecting data tables show declared DataTable names in the dropdown
• Free-form parameters show a text input with the DEF file default value pre-filled
• Live preview of the assembled instruction updates as you fill in parameters
• Optional trailing empty parameters are automatically trimmed from the output
• Insert with the Insert button or Ctrl+Enter / Cmd+Enter; cancel with Escape
• Accessible via the wand icon on each instruction in the Instructions panel, the Wizard button in the Instruction Help panel, or the Command Palette (CRBasic: Parameter Wizard)

Instruction Panel

A dedicated sidebar panel for browsing all CRBasic instructions, accessible via the CRBasic icon in the Activity Bar:

• Alphabetical list of 500+ instructions with category labels
• Search functionality to filter instructions by name
• Category filter to show only specific instruction types (Measurement, Math, Data Tables, etc.)
• Filtered by datalogger model -- only shows instructions supported by the configured logger
• Click the wand button to launch the Parameter Wizard for guided instruction building
• Click the + button to insert an instruction at the cursor position (with snippet tab stops)
• Click the ? button to open the Campbell Scientific documentation for that instruction
• The panel only appears when editing CRBasic files

New Program Template

Quickly scaffold a new CRBasic program:

• Use File > New File... > CRBasic Program or the Command Palette (CRBasic: New Program)
• Prompts for the target datalogger model
• Inserts a standard program template with the correct first-line datalogger declaration

Auto-Detect Datalogger Model

The extension reads the first line of CRBasic files (e.g., 'CR1000X Series Datalogger) to automatically detect the target model, overriding the global setting on a per-file basis. This means each file can target a different datalogger without changing settings.

Configuration

This extension provides the following settings (accessible via File > Preferences > Settings):

Document Outline Colors

Customize symbol colors in the Document Outline panel via workbench.colorCustomizations in your VS Code settings:

Keyboard Shortcuts

Online CRBasic Help

CRBasic help for each specific Campbell Scientific data logger can be found at:

• CR1000X and CR1000Xe
• CR6
• CR300 and CR310
• CR350
• GRANITE6
• GRANITE9
• GRANITE10

Supported File Extensions

.crb, .cr1x, .cr300, .cr6, .dld

Known Issues

• IntelliSense help text is not yet complete for all CRBasic instructions. Coverage is expanding with each release.
• Not all of the latest datalogger instructions are included yet (but coverage is growing -- 500+ instructions and counting).
• Block validation (If/EndIf, For/Next) is automatically skipped in files containing preprocessor conditionals (#If) since conditional compilation makes block matching unreliable.

Requirements

VS Code 1.100.0 or later.

Current Maintainers

• Gary Roberts (Daiwalkr)