This project contains a comprehensive documentation of the original VisiCalc source code for the Apple II, focusing on creating a fully annotated version of the 6502 assembly code.

VisiCalc was the first spreadsheet program for personal computers, originally released for the Apple II in 1979. This project aims to document the original 6502 assembly code to preserve this important piece of computing history and make it more accessible for study.

The commented code has been split into multiple files for easier navigation:

1. vc_complete_commented.s - The first part of the commented code (approximately 3,600 lines)
2. vc_commented_2.s - Command processing routines
3. vc_commented_3.s - More command processing routines
4. vc_commented_4.s - Additional command processing routines
5. vc_commented_5.s - Further command processing routines
6. vc_commented_6.s - Display handling and cell formatting routines
7. vc_commented_7.s - Formula evaluation routines
8. vc_commented_8.s - File I/O and printing routines

Each instruction in the assembly code has been annotated with detailed comments explaining:

• The purpose of each instruction
• The meaning of memory locations and registers
• The flow of control through the program
• The functionality of different routines

The original source code was disassembled by Brutal Deluxe Software using The Flaming Bird Disassembler. This documentation project preserves the exact original code structure while adding educational comments.

1. System Initialization Routines
2. Keyboard Input Handling
3. Screen Manipulation
4. Memory Management
5. Character Processing
6. Command Parsing
7. Error Handling
8. Formula Evaluation
9. File I/O
10. Printing Routines

VisiCalc is considered the first "killer app" for personal computers and played a significant role in legitimizing personal computers as business tools. This documentation aims to preserve the technical implementation details of this groundbreaking software.