17

Disk addressing failure. Data written
starting at band 64+32+16+1, TRACK 1,
segment 10+8+7 can sometimes be read
on the same band and track on segment
9+8+7.

Much experiment has shown that
writing on SEG=9+8+7, BAND = 64+32+16+
4+2+1 TRACK=1 causes the data on
band 64+32+16+1 TRACK 1 segment 10+8+7
to be coped onto segment 9+8+7, same band
and track.

An attempt to make the same thing happen
with a simpler program resulted in writing a
couple of words of data from BAND = 64+32+16
+2 TRK=0, SA = 11+8+2 onto the same
place as above. The data that was written
was not in core at the time of the writing but
it was recognizably data written earlier by
this phase of the disk tester. Frankly, I
am confused at this point.