Skip to content

MBASIC 5.21 Help

Welcome to MBASIC 5.21! This help system is organized into three sections:

📕 Language Reference

Learn the BASIC-80 language - statements, functions, operators, and data types.

Common topics: - Statements - PRINT, FOR, IF, GOSUB, etc. - Functions - ABS, SIN, LEFT$, etc. - Data Types - Integer, String, Single, Double - Operators - Arithmetic, comparison, logical

Quick examples: - Hello World - Loops and Control Flow

📗 About MBASIC 5.21

Learn about this implementation of Microsoft BASIC-80 version 5.21.

Topics: - Getting Started - Your first program - Features - What's implemented - Compatibility - How it compares to original MBASIC - Extensions - Modern enhancements - Architecture - How it works

📘 UI-Specific Help

Learn how to use the interface you're currently in.

Select your interface: - Tk (Desktop GUI) - Graphical interface with menus - Curses (Terminal) - Full-screen terminal interface - Web Browser - Browser-based interface - CLI (Command Line) - Simple command-line interface


Most Commonly Searched

Language Basics: - PRINT statement - Display output - INPUT statement - Get user input - FOR...NEXT loops - Repeat code - IF...THEN...ELSE - Conditional execution - GOSUB...RETURN - Subroutines

File Operations: - OPEN statement - Open files - PRINT # statement - Write to files - INPUT # statement - Read from files - CLOSE statement - Close files

Common Functions: - String functions - LEFT, RIGHT, MID$, LEN - Math functions - SIN, COS, SQR, ABS - Type conversion - CINT, CSNG, CDBL


Tips

  • Use the Search box above to find specific topics
  • Press {{kbd:find:curses}} to search within the current page
  • Click ⌂ Home button to return to this page
  • Click ← Back to go to the previous page

About This Implementation

MBASIC 5.21 is a faithful recreation of Microsoft BASIC-80 version 5.21, originally released in 1981 for CP/M systems. This modern implementation maintains 100% compatibility with original MBASIC programs while adding optional modern conveniences.

For more details, see About MBASIC.