Detecting Hard Drive Activity

[mikey76]

What is the simplest way to pick up a logic 1,0 signal to indicate when a hard drive is being accessed? I have 3 drives .... can't tell except on the C drive.

(PS Retired Electronic Eng and previous Electronic Tech)

 

[Killbat]

Don't they still put actual "activity LED" connections on hard drive controller boards? They still did up to a few years ago, I don't know about the very newest drives. If they don't have an obvious header for it, maybe the IDE chip has a pin for it.

 

[Scootin159]

oooh, this would be fun to have 1 LED per HDD, rather than 1 LED that is on if any of my HDD's have activity.

 

[Evadman]

Hey, now that would be cool. You could set up a LED array in front of your computer. Maybe the Serial Drives will have a connector on the HD itself.

 

[mikey76]

Yeap...that is the general idea.

Anyone know a URL for the IEEE spec for the 40pin HD data lines? Or for WD connections. Can't seem to find the info on WestDig .com

 

[blahblah99]

Im not sure if this is the easiest way to go, but I would use a PIC microcontroller and interface it to the 40/80 pin ide cables to detect when each hard drive is being accessed.

The 16F84A's have 13 I/O lines, so that leaves you with room for 6 HDs. The pic itself is capable of providing up to 25mA each i/o which is more than enough for led's.



EDIT: An even SIMPLIER way to detect hard drive activity is to find the right ide pin and use that to drive a transister and LED.

http://an.hitchcock.org/repairfaq/REPAIR/F_Pinouts2.html#PINOUTS_028 are the specs you are looking for.

 

[mikey76]

blahblah99 - Thanks

That goes a long way towards the answer! I am not really sure what some of the signal definitions are though.

Thanks again