The ResiDOS Homepage

(ResiDOS boot screen)

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Update 1st June 2016! ResiDOS v2.30 is now available. This adds SDHC and SDXC card support for SD/MMC card interfaces.


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

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
You can contact me by sending an email to my full name (without any space between first and last names), at
Thanks to World Of Spectrum for hosting this site
Last updated 1st June 2016