VDOS
From CPCWiki - THE Amstrad CPC encyclopedia!
The disc operating system VDOS was developped by the german company Vortex. It was provided for use with the Vortex Disc Drives from Vortex (F1-D, F1-S, F1-X, M1-D, M1-S or M1-X).
VDOS was supplied on an EPROM, and was released in the versions: VDOS 1.0, VDOS 2.0 and VDOS 2.11
The VDOS ROM also contained a machine language monitor.
VDOS supported as first DOS the Vortex format, which become a standard format later on.
Manual
Vortex Vdos 2.0 Manual (pdf) (also describes how to upgrade from VDOS 1.0 to 2.0)
