A couple of days ago I published a list of mass storage controllers I've got
available.  It turns out I have documents to go with the following.
    MSC (later called XEBEC) 9305 GPIB-ST506 HDC for 1 drive.
    MSC (later called XEBEC) 9391 S-100-ST506 HDC for 2 drives on double height S-100
board
    XCOMP S-100 HDC for 8" (SA1000-Series) drives.  Two board set called
"STS"
    INTEL iSBC 215 "Universal" Fixed Disk Controller with on-board 8089
intelligent I/O controller
the remainder are still without documents.