AT&T 3B2 Off-Line Diagnostic Manual page 525

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Phase Descriptions
Phase '#17
Phase Name:
Type:
Function:
Tests:
Time:
Warnings:
Notes:
HDC XD Seek Tests
XDC Seek Tests (xd<:-3)
Demand
This phase tests the ability of the XDC to seek to various regions of hard disk.
Test 1 - uses the specify command to initialize the NEC chip.
Test 2 - returns the heads to cylinder O.
Test 3 - seeks to cylinder O.
Test 4 - reads sector 0 to determine the physical size of the disk.
Test 5 - tests for read command completion of disk.
Tests 6 through 25 - seek to various regions of diskO.
Tests 26 through 100 - no tests run.
Tests 101 through 125 - are identical to Tests 6 through 25 except disk1 is
tested.
8 seconds
None
This phase is designed to test the ability of the heads to move from cylinder to
cylinder. The disk is divided into four regions between the rim and the spindle
of the disk. The cylinders selected for the seek tests and the test sequence are
as follows:
rim
+---------+---------+---------+---------+
spindle
----------»---------»---------»---------»
~---------~---------~---------~---------­
--------------------»-------------------»
~-------------------~-------------------­
------------------------------»
~-------------------­
------------------------------»
~-----------------------------­
--------------------»
~-----------------------------­
----------------------------------------»
~----------------------------------------
The sequence (from top to bottom in the figure) of seeks selected is designed to
perform seeks between any adjacent regions in both the forward (toward the
spindle) and backward directions. The sequence requires no "special trip" for
the heads to set up for the next seek. At the end of all the tests, the heads
should be at cylinder O. Normal seek (not buffer seek) will not be tested since
it is a feature not used by XDC. Overlap seek will be attempted when more
than one disk drive is equipped.
EXPANSION DISK CONTROLLER DIAGNOSTICS 11-31