The ResiDOS Homepage

(ResiDOS boot screen)

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Update - 8 July 2009

A major new release of ResiDOS, v2.25, is now available!

The most important new features are commands and functions allowing new extended streams and channels to be used. A new package, Channels v1.00, has also been released which provides channels for accessing disk files, string variables, memory regions, text windows (both +3e-compatible and VT52 emulation mode) and more. For details of these, see the extended channels page and the channels package page.

For machine-code programmers, the programming section has now been completely updated and revamped, and contains masses of information on writing programs to use ResiDOS features, and details of how to write your own packages to add further capabilities to the system. There are also a whole host of useful new calls available in the ResiDOS package reference.

Finally, there is a number of bugfixes and other minor improvements.

For full details of all the changes, see the what's new page.


ResiDOS is an extension to ZX Spectrum BASIC that operates with various add-on interfaces providing extra memory and hard disk or compactflash/SD card interfaces.

ResiDOS installs itself into your interface's onboard RAM together with a modified copy of the Spectrum ROM, and then provides you with extra BASIC commands for accessing files on the hard disk or compactflash card, and using the extra RAM on your interface. It also provides a comprehensive task manager which can be reached using the NMI button and allows you to instantly switch between a number of programs or games running on your Spectrum.

For further information on ResiDOS, choose one of the following links:

Getting started:

Using disks and cards:

Additional features:

Reference information:


Links to other useful sites

My sites and projects:

Offline manuals containing ResiDOS manual (may not be fully up-to-date):

Other software for/related to ResiDOS & ZXSpectrum +3e:

General Sinclair news and discussions:

Places to buy ready-made interfaces, or help build your own:

Alternative BASICs and Interface II ROMs to run with ResiDOS:

Other interesting Sinclair-related sites:

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Maintained by Garry Lancaster
Thanks to World Of Spectrum for hosting this site
Last updated 8th July 2009