IDE controllers

[Bill Blue]

In <1990Nov21.093114.15468 at grian.cps.altadena.ca.us> alex at grian.cps.altadena.ca.us (Alex Pournelle) writes:

}I speak from experience...
}You would do well to avoid XENIX and IDE drives.  I have a system with
}just this configuration--and it will lock up every 6 to 8 hours
}unpredictably with the hard-disk access light on.  It is dependent on
}the controller, but even more dependent on the hard-disk (which, since
}IDE stands for Integrated Drive Electronics, is the real controller in
}these things).  The drive is a Conner CP-3104, the 100Mbyte Conner drive
}that Dell and Compaq use at great length; my spies at SCO say this drive
}is not completely emulating the WD-1010 and -2020 controllers, the only
}two IDE controllers they "officially" support.  (I've never heard of
}'em--the only Western Digital controllers I know of in IDE that are
}current stock items are the WD-140, -240, and -440; but again, that's
}the board that plugs into the computer, not the controller which is on
}the drive.)

I too speak from experience.  The problem with IDE drives and Xenix is
not the drive or the controller ON the drive.  It is with the adapter
card that plugs into the motherboard and connects to the drive.  Some
of the adapter boards are very sensitive to the buss timings of the
motherboard.  They will do anything from refuse to boot Xenix
altogether to occasional lockups and other strange behavior.  It is
the adapter, NOT the drive.  Adapters that I have found work
consistently in a wide variety of motherboards are by Priam and Conner.

Using good adapter boards, I have installed quite a number of Xenix
systems on IDE drives with no problems.  In fact I use a Conner CP3104
on one of my test systems day in and day out.  IDE drives are
basically RLL and you can expect the same general performance and data
throughput as you would with any other quality RLL drive/controller
combination.

--Bill