PCjs Machines

IBM PC XT (Model 5160) with IBM VGA

NOTE: Unlike most IBM PC machines on PCjs, the DIP switches on this machine have been set to indicate four floppy disk drives (0xxxxx00) instead of the usual two drives (0xxxxx01). This can result in some confusion, depending on which version of DOS you’re using and what your expectations are.

For example, PC DOS 3.20 will assign drive letters A-D to the floppy drives and drive letter E to the hard drive, whereas MS-DOS 5.00 always starts with drive letter C for any hard drives, regardless of the number of floppy drives; since this machine has only one hard drive, MS-DOS 5.00 will assign drive letters D and E to the 3rd and 4th floppy drives.

PCjs does not interrogate the operating system’s drive letter assignments, so the removable drive letters displayed in the PCjs UI will always be A-D. The UI could display drive numbers instead of letters (eg, 1-4), but that would be more confusing for the average user and the typical machine, so I’ve decided to leave things as they are.

Documents

IBM 5160 Guide to Operations
(Apr 1984)

IBM 5160 Technical Reference
(Apr 1983)

[GitHub Source]