Enabling The Offline Selftest Routines - Seagate ST251N Product Manual

2.7.1 ENABLING THE OFFLINE SELFTEST ROUTINES
To enable the test, short the following pins to ground at the SCSI con-
nector: 2, 12, 16 and 32.
The selftest is in three parts. They will cycle in order until power or a
grounding jumper is removed, or until 10 complete passes.
The LED will remain on during the test and will turn off if an error is
detected or a jumper is removed. The LED will flash continuously if
10 passes are completed without error.
Part One: All sectors in the user data area are read starting with logical
block zero.
Part Two: This is a butterfly seek/read test. Starting at the center of
the user data tracks, the unit will seek outward and inward by incre-
ments until the limits of the user data tracks are reached. A one-track
read is performed to verify position.
Part Three: This part performs a write/read compare on all sectors of
the diagnostic cylinders using data pattern 6DBH. The diagnostic cyl-
inders are located at an inner region on each media surface. Any
unrecoverable errors will terminate the test and turn off the LED.
2-6 ST251 N/277N Product Manual, Rev. B