Faking Harddrive activity?

[TheRagingGerbil]

I have an old drive that I am in the process of modding windows into the top and sides. The drive is dead and is only going to be used for visual effects. My question is has anyone seen or done a small electronic circuit to fake harddrive activity? I could do it in VB, but I don't want to be so careful that I need the drive to actually function after being modded.

Thanks.

 

[fat-tony]

Are you trying to move the heads around, or just flash an LED?

 

[TheRagingGerbil]

Move the heads. I'd like to do it without having to hook it up to my mobo. I thought about cycling power on and off, but I think the life of the drive would be severely shortened.

 

[fat-tony]

Hmmm... I'll think about it this afternoon. You could probably do it with a cheap microcontroller, if you have access to a programmer and stuff. I'll ponder though...

 

[TheRagingGerbil]

Microcontrollers I got. That is kind of what I was thinking. The project I am working on already has two basic stamps in use. I also have a drawer full of 16F84's which could be used. Was thinking a simple clock circuit could be used if I could find the respective pins to use...

 

[theshadow27]

this has been done before:
http://zapwizard.com/Mods/RealHD-IDE/index.html

 

[TheRagingGerbil]

Thanks shadow!

 

[fat-tony]

I was thinking you could probably position the head pretty accurately using a micro with PWM and a transistor (to handle the current through the head coil). We hooked the coil up to a stereo once and got some (surprisingly good) sound out of it.

 

[theshadow27]

I was thinking you could probably position the head pretty accurately using a micro with PWM and a transistor (to handle the current through the head coil). We hooked the coil up to a stereo once and got some (surprisingly good) sound out of it.

dont you think thats overcomplcating it, considering that the micro is already on the HDD board, and already containes the proper control algoritioms, ect...

check the link

 

[fat-tony]

check the link

That's assuming you can find the correct pins on the board. In the link that looks like a super old hard drive, and the functionality they used could all be integrated into a single chip on new drives. It all depends on the drive I suppose.

 

[theshadow27]

out of curiosity, i took a peak at some of the newer broken drives that i have laying around.

a Maxtor 40gb has all 4 chips on one side. there is a 1024x4 SDRAM chip (4mb cache), a IDE interface of some sort, an "advance hard drive controller" and a "hard drive controller" (per google search) -- but i cant get the datasheets on any of them..

a WD 80gb has no IC's on the outside, and the two that are on the underside have "Western Digital" printed on them. no part #s, no data sheets.

So I suppose you are right, on any newer hard drive it is going to be impossible to find the pinouts, and you’ll probably have to rig some sort of interface right to the coil. my recommendation is to find some old SCSI or era 486 IDE33 drive that has big DIP chips on it and tons of "TP" or test point dots. Any computer shop that deals with older machines will have tons of them lying around (there is a place down the street that sells old PC parts by the crate, lol) this will increase your chances of success by a ton and a half.