Adaptec SCSI Controller and 386/ix

[neese at adaptex.UUCP]

>I have added a 2nd drive (Fujitsu M2614S SCSI 3 1/2") and a
>Cipher SCSI Streamer ST150S to a Compaq 386/20. The Controller is
>Adaptec 1542 A.
>1 st. Question : The installation of the drive was quite easy, no
>formatting errors nor verifying errors, no problems with making
>file systems and no problem with  mounting the file systems.
>But when I copied some files to the drive, I got sometimes the
>error message :
>              *** Uncorrectable data error in sector ***
>or, when the controller is configured for no auto-sense :
>              *** Unknown error in sector ... ***.
>Are there some explanations for this behaviour ? Do I have to set
>the jumpers on the Adaptec other than the default ?

You not have to change any of the default jumpers.  The only jumper you may want
to install is the jumper on J1 pin pair 1.  This will allow synchronous
negotiation to occur.  By disabling the auto-sense feature, the driver looses
the ability to know what error occurred on for a given command descriptor
block.

An uncorrectable data error, if it is a true representation of the SCSI error
returned from the device, is sense key 3 error code 0x11.  This indicates a
hard media error.  Although I have seen this error from devices before and
it was also caused by early termination of the data transfer or a SCSI bus
phase change to early.   If the error detecting part of the driver is looking
for the host adapter status and it got a 0 value, then the 1540 did not detect
an illegal bus phase change or any other bus error.  That does not rule out
what happened in the drive controller.  The drive obviously reported the error
or you would not have gotten the message.
You can grab the SCSI.EXE and SCSICNTL.EXE programs off of adaptex.  They may
be of help.  The SCSI.EXE is a diagnostic and the SCSICNTL.EXE is a program
that allows you to see the firmware revision of a device and to reprogram
the SCSI device to fit your needs.

I haven't used the Fujitsu drives, so I don't know anything about them.

>2 nd. Question : I have not installed the Cipher yet. Are there some
>known problems with this streamer ?

I have had a Cipher ST150S2 on 'adaptex' since April 89.  No problems with
this drive as long as you have firmware version G76R or later.  The versions
of firmware before this had a bug in it.  After a rewind command was sent
and was not followed by an unload command the drive would sometimes refused
to operate after that.  The only way to recver from this was issue a hard
SCSI bus reset.  Not a good thing to do while a system is running as that
would also reset the all the other devices on the bus.  I beleive that Cipher
is currently shipping version G76T.  That is the version of firmware I have
on my drive and I have had absolutely no problems with it.

			Roy Neese
			Adaptec Central Field Applications Engineer
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