as a kit with a disk controller chip, a ROM chip, and a few logic chips, to be installed inside the computer.
*Advanced Disc Filing System (ADFS) is a successor to Acorn's DFS.
*AMSDOS is for the Amstrad CPC computers.
*GDOS and G+DOS is for the +D and DISCiPLE disk interfaces for the ZX Spectrum.

Main OSes