Welcome to the Z88 User Guide - edition 4.7

This is the revised User Guide for the Cambridge Z88, being updated with all new features and improvements that has been added into the "OZ" operating system ROM, both on application and system level by the Z88 Development Team since the last official V4.0 UK ROM was released by Cambridge Computer in 1989.

The Z88 Development Team reverse-engineered the V4.0 ROM into source code in 2003 and has since then done substantial re-organisation and optimisation of the existing OZ code base, now fulfilled many of the original end-user wishes expressed in the independent end-user "Z88 EPROM" publishing made available in the early nineties.

Per Svensson - a dedicated Z88 user - did all the OCR scanning of the printed 4th edition and converted it to HTML. With his permission, we continued the process, replaced all virtually drawn screenshots with live snapshots from the Z88 emulator and finally converted it into this wiki.

Major improvements developed since original release by Cambridge Computer

  • Save and Load Files directly to the File Area - no need to save the file to RAM first. Use :EPR:1, 2 or 3 from directly from the Application.
  • Run Application in RAM - No need to have applications in Flash or EPROM card, just get and use RAM. 
  • Multiple Language & Keyboard selection - The popular foreign ROM's can now be selected; choose from a range of countries, use different keyboard layouts and see the change of languages in the localized date names in the ClockCalendar and Diary
    • Supported languages are:- UK (default) USA, French, German, Spanish, Italian, Danish, Norwegian, Swedish and Finnish
  • Filenames may now use the complete ISO character set, allowing to use characters such as é and å in filenames.
  • Fast Serial Port - all speeds and protocols supported with reliable file transfer up to 38400 baud
  • Eazylink2 connects to 21st century Desktop computers with support for the original file transfer Imp/Export popdown
  • XMODEM and YMODEM protocol added to Imp/Export popdown
  • BBC BASIC V3.10. Now includes the "patch" integration from the V2.2 / V3 UK ROM
  • Fast Backup using Flash cards support in Filer and Flashstore. Flash cards are FORMATTED by the Z88 itself. - No need to use EPROM Cards or the EPROM Eraser to FORMAT them
  • Terminal supports all VT52 commands
  • Main HELP pages repopulated and expanded  from ROM V3.0 UK (from OZ 4.0)

  • System Info page in Index that displays OZ build release information, battery status and free system resources

  • Alarms can be saved to file (for backup and restore across soft reset)

  • EPROM is checked that it is empty before cataloguing the first time

Available editions of Z88 User Guide

The following table lists the released editions of the Z88 User Guide, provided by the Z88 Development Team and others:

Release editionDescriptionDownload / reference link
3.0Online browsable scanning of Cambridge Z88 User Guide. Can be downloaded as PDF or ePub file.archive.org
4.0Wiki-format of final fourth edition as it were bundled with a Cambridge Z88 Computer.Z88 User Guide V4.0
4.7Latest edition, containing all feature updates of OZ releases since 4.1W.I.P.

Latest online edition

We're constantly editing the user guide, reflecting the current development of the Z88 operating system. Click on chapters as seen below, or use search to specific details.

Recent updates


Navigate space
The selected root page could not be found.