@tomjennings These are the MS-DOS 2.00 disks I got with a Seattle Computer Products 8086 S-100 system I got a couple of years ago: http://annex.retroarchive.org/disks/8 Inch Disks/ms-dos-2.00-disks.zip. The system has a serial console and 8" & 5.25" disks. Lots of source code for DOS in there. (needs to be extracted from the disk images)