The Z-Machine Standards Document

Version 1.0

22nd June 1997

two misprints corrected, 9th August

resources appendix updated and discovery added to header table, 4th September

resources appendix updated and annexe covering Quetzal added, 30th September

corrections and clarifications added, 21th February 2014 - David Fillmore

• Preface
• Overview of Z-machine architecture

Fundamentals

• 1. The memory map
• 2. Numbers and arithmetic
• 3. How text and characters are encoded
• 4. How instructions are encoded
• 5. How routines are encoded
• 6. The game state: storage and routine calls

Input/Output

• 7. Output streams and file handling
• 8. The screen model
• 9. Sound effects
• 10. Input streams and devices

Tables

• 11. The format of the header
• 12. The object table
• 13. The dictionary and lexical analysis

Instruction Set

• 14. Complete table of opcodes (with Inform assembly syntax)
• 15. Dictionary of opcodes

An Unusual Font

• 16. Font 3 and character graphics

Appendices

• A. Error messages and debugging
• B. Conventional contents of the header
• C. Resources available (with WWW links)
• D. A short history of the Z-machine
• E. Statistics
• F. Canonical story files

Related standards documents

• Quetzal: a common format for saved-game files
• Blorb: An IF Resource Collection Format Standard
• The Treaty of Babel: Software and a standard for IF bibliography