This is the contents of the 6530 RIOT chip for the floppy controller
(unknown revision, looks like a slightly patched 901869-01)
Ville Muikkula reports that his 8250LP has a little circuit board inserted
in the place of the floppy drive controller 6530 RIOT chip. Located on this
circuit board are the original 901869-01 and a 2732 EPROM chip that has a
label with part number 251474-01B, and agrees with this dump. The
extraneous 3 kilobytes of the 2732 are filled with $aa.