ExtraDrives information


ExtraDrives is a disc BIOS emulator which installs either as a DocsBoot+ extension, or using a boot intercept technology I developed some years ago which I call VersaBoot.

ExtraDrives loads into memory before DOS, and allows DOS to see up to eight hard discs (MFM, RLL, ESDI or IDE drives are supported) in addition to those it can already see (the existing drives can be of any type). ExtraDrives only takes up 3KB of base memory, or if it can load high on your system (some chipsets allow it to load high), then it appears to be a 4KB ROM (there were problems with some diagnostic programs and the idea of a 3KB ROM). The drives ExtraDrives adds can be used on any DOS version 5.00 or later (earlier versions do not work with more than two drives) without any other drivers.

ExtraDrives does not require an interrupt for the drives it supports. This allows a crowded system to still have additional drives added. This does not slow DOS down, since DOS is singletasking anyhow, and ExtraDrives is not meant for use with the more advanced operating systems like OS/2 (though it does work), since they provide faster drivers for many hard discs themselves (though they usually require an interrupt).

The current version of ExtraDrives is version 0.14. ExtraDrives is not currently available to the general public. If you are interested in seeing ExtraDrives, please email me, and we should be able to arrange for you to see it. Sorry for the inconvenience.


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