Epson 10020 - Manual (Page 181)

Before it performs any checks, the program determines the
number of diskette drives installed in your computer. If you
have more than one drive, you see this prompt each time you
select a test:
Check which drive (A/B)?
Press A or B and then Enter. If any errors occur, record the
error code and message and contact your Customer Care
Center.
Sequential Seek Check
This test checks the ability of the read/write heads to locate any
part of the diskette. This action by a read/write head is called a
seek. During this test, each head seeks sequentially from the
innermost track to the outermost track. The innermost track is
track 39 for 360KB diskettes and track 79 for 720KB diskettes.
Select option 1 from the menu to start this test. The program
displays the number of each track it finds. For example, with a
360KB diskette, the first message you see is:
Current track is 39
The track number counts down (from 39 or 79) to 0. The seek
is performed by each head, so you see the count twice. If no
errors occur, the menu reappears.
Random Seek Check
This test is identical to the sequential seek check, except that
the seek operation is performed on each track in random order
instead of sequential order. Select option 2 from the menu to
start this test.
D-24 Performing System Diagnostics