Re: What could cause this.

Michael H. Warfield (mhw@wittsend.com)
Tue, 10 Nov 1998 12:25:14 -0500 (EST)


Duncan Stirling enscribed thusly:

> Ever since I started working with 2.1.117, found something odd happening
> on my computer. The my HDD light remains on, though there often is no
> active process using the hard disk, nor trying to access the hard disk
> controller.

You failed to mention what time of hard disk. Was it SCSI, IDE,
MFM, ESDI, or what. Reason I mentioned the two older hard drive standards
is that I have seen that effect on MFM and ESDI drives. The "drive select"
for those drives was independent of drive activity so, if you looked at the
light on the hard drive, once accessed, the drive light would stay on.
That is NOT the HDD light that is wired to the controller, however. The
controller light was driven by drive activity and not drive select. Seems
like I have seen a similar effect with certain IDE drives where an LED
connected to the LED jack on the drive would remain lit while and LED
connected to the HDD LED jack on the motherboard or controller would
blink with activity.

I guess that brings up the next question... Is this an LED on the
drive itself or an LED connected to the motherboard or controller?

If it's an activity LED, it could indicate a lost interrupt (I've
also seen that) but that often means that the system then hangs for the period
of a timeout. Does the LED eventually go out or is it permanently on?
Does your system continue to run and access the harddrive, or is it dead?

> I haven't heard of anyone else mentioning this occurring in any other
> system. So I feel so terribly alone, can anyone shed any light to where
> I might start looking after the obvious has been exploited.

Mike

-- 
 Michael H. Warfield    |  (770) 985-6132   |  mhw@WittsEnd.com
  (The Mad Wizard)      |  (770) 925-8248   |  http://www.wittsend.com/mhw/
  NIC whois:  MHW9      |  An optimist believes we live in the best of all
 PGP Key: 0xDF1DD471    |  possible worlds.  A pessimist is sure of it!

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/