This:
- adds support for host filesystem access from the Enterprise, allowing use of software distributed as .COM or .BAS;
- allows the C-1540 and 1541 to write to disk images and makes D64 files no longer read-only; and
- experiments with emulation of the BeebSID expansion on the BBC Micro (though noting that most of the SID compilation tune discs are broken to varying degrees with the 1770 DFS).