                               EIDETEST



INTRODUCTION

EIDEtest was written to check for the RZ-1000 EIDE controller flaw
commonly found on PCI motherboards with Mercury and Neptune chipsets.
It does not check for the flaw directly. Rather it does a high level
test, ensuring that what is written to a file is what comes back
later.


BACKGROUND

Please read the enclosed FAQ, RX1000.TXT for more information on the
flaw.

In covers such topics as:

*    Reporting the flaw.

*    Do you likely have the flaw?
*    Recognising the RZ-1000 chip.
*    Making your OS immune to the flaw.
*    What can you do if you find the flaw?

HOW TO USE

Under DESQview, Windows, Windows For WorkGroups , NT or OS/2
emulation, all under DOS emulation and run the program:

     EIDEtest.exe C:

where C: is your EIDE drive partition that has at least 7 MB of free
space on it for the test.

Just follow the instructions on the screen. In phase 2 of the test,
you will need to run other programs to generate DMA activity while the
test is running.

DOS, DESQview, Windows, Windows For WorkGroups, and Windows-95 only do
one i/o at a time. The only ways to generate the simultaneous DMA that
triggers the damage is:

*    Backup some files to floppy with MWBackup, MSBackup, Norton
     Backup or other high performance floppy backup program with
     simultaneous disk i/o turned on.

*    Backup a file using your mag tape backup software with
     simultaneous disk i/o turned on.

Under OS/2, Warp, NT, Linux, SCO XENIX, UNIX etc. it is much easier to
generate the simultaneous DMA since these operating systems do more
than one i/o at a time. (This is a two-edged-sword. This also means
there are more ways to corrupt your files, so the flaw is likely to
cause more damage.) There are many ways to generate the simultaneous
DMA that triggers the damage:

*    Format a floppy.

*    Browse some files on your SCSI hard disk.

*    Browse some files on your SCSI CD-ROM.

*    Scan a document with your SCSI scanner.

*    Backup some files to floppy with MWBackup, MSBackup, Norton
     Backup or other high performance floppy backup program with
     simultaneous disk i/o turned on.

*    Backup a file using your mag tape backup software with
     simultaneous disk i/o turned on.

Your experiments may run slowly because of EIDEtest's disk overhead.
You can continue the test as long as you want, days even. The test
will stop as soon at detects even one error or if you hit ESC or the
space bar.


INTERPRETING TEST RESULTS

If the test passes, you probably don't have the flaw. Sometimes the
flaw does not manifest immediately. You might have to run the test for
many hours in the background for the problem to show up. Running the
test under pure DOS does not prove much since it is impossible to
generate background interfering DMA activity.

If the test fails, it means you your hard disks are not working
properly. It does not diagnose why. If you have a PCI motherboard with
a Mercury or Neptune chipset, the odds are that the RZ-1000 is the
cause of the trouble. However, overheating, other unrelated hardware
failures or design flaws, or software bugs can also cause you hard
disk to make errors.


FREEWARE STATUS

EIDEtest, C++ source and executable may be freely copied and used for
any purpose except military. Unlike many of the other Canadian Mind
Products utilities, it is free, not shareware. You are also free to
port the code to other operating systems so long as you leave the
copyright banner intact.


CONTACTING THE AUTHOR

The author, Roedy Green is a computer consultant who prefers to work
on Forth, C++, Delphi, DOS, OS/2 and Internet Web projects.

If you send me $5 (US or Canadian) to cover duplication, shipping and
handling I will send you a diskette containing four programs:
PowerQuest IOtest, Gazelle DMAtest, and both EIDEtest and CDtest from
Canadian Mind Products.

Please report which machines you find the flaw in, and which software
and fixpacks you were using at the time. Send email to:

     Roedy@bix.com

or discuss this problem on the Internet newsgroup in:

     comp.os.os2.bugs.

You can also write via snail mail:

Roedy Green
Canadian Mind Products
#601 - 1330 Burrard Street
Vancouver, BC  CANADA
V6Z 2B8
(604) 685-8412

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