Guide Drive-independent Activity LEDs -Guide

Posted a whie ago, revived for the Guides area:


http://www.zapwizard.com/guides/ide
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This guide will show how to make a separate LED to show exactly which drive in your system is active.

I did this to three 80 conductor cables without any problems, it has also been done on rounded cables without problems.

First off this Mod only works on IDE Harddrives.
Now for a little information:

An IDE connector has 40 pins, we want Pin 39, this pin is dedicated to driving an activity LED. And is controled by the harddrive.

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Pin 39 is wired to a Motherboard like the above.

The LED jumpers' negative pin is simply ran through two diodes (to keep the two channels sperated), then directly to pin 39.
The 10K resistors are to make sure that when the Diode is off, the IDE activity pin's voltage is kept at VCC.
The positive side of the LED is ran through a 33ohm current limiting resistor to VCC (Usually about 1.6v)
Well, we will simply bypass all this and run the LED directly to pin 39 in the IDE cable it's self.
You can do this because Pin39 has nothing to do with the operation of you drive, just the LED.

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The IDE Cable

I am doing this example with a 80 conductor cable.
If you use a 40 conductor cable Pin 39 is simply the second to last wire (NOT on red side)
Since and 80 Conductor cable has a ground wire paired with each signal wire.
So Pin 39 is the THIRD TO LAST WIRE on MOST IDE cables
(As some cables are different check your cable first with an ohm or continuity meter first)

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Cut carefully on both sides of the wire.

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Separate the third wire:

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Then clip it in half (AHHHHH, don't worry your drive will still work, unless you cut the wrong wire)

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Strip the wires, carefully.

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(I added a quick disconnect and used heat shrink tubing to cover the connector)
The one on the Left is for the First IDE device, the one on the right is for the second IDE device.
Also note that when the second IDE device is ran the LED may still go off on your Motherboard
(Dimming your custom LED, this does not happen in my system, but still I disconnected my IDE LED)
To fix this either disconnect the one on the motherboard, or Clip Pin 39 between the
Device connectors and the Motherboard connector.

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The LED's

First you have to choose a resistor value that will keep the current on the LED's in spec.
I choose to run the LED's off the 5v line from my power supply, so I choose 150ohm resistors.
This should make the current for each LED 33 milliamps.
Mount your LED's however you want, I used some nice, but cheap LED's w/mounts from RadioShack
I didn't need ultrabrights as my case is behind a desk door most of the time.

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Then wire each LED as the the schematic above,
5 volts runs to the resistor, then the resistor connects to the positive side of the LED,
the negative side is connected to Pin39 on each device you you have.

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It should look something like this:
Connect the common 5V wire to 5 Volts
Connect the negative wire of each LED to Pin39 on each IDE device and you are set!


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How it looks:




The second animation is from Enak, He used rounded cables

 

I was about to say that it might have been easier to connect the led directly to pin 39 behind the connector on the hard drive, but why risk screwing up a $150 Hard drive when you can do the same to a $10 cable...

 

Nice work, must get around to doing this

Rob.

 

While i do really like this mod, it's nice to see what pin outs are use for various systems...

one the pin scematics are found, the posibilities are endless..

nice work Zap

 

And this will work with a lappy CD-ROM connector to a standard IDE cable via an adapter? I need to get this done...

 

It might, it depends whether or not the manufacturer used it or not. All the IDE CD-ROMs/CD-RW's/DVD's I have used did not work with this mod.

I guess they don't use that signal wire because they already have an LED on the front of the drive.

But you can use my other guide to re-locate the LED.
Although solding in a laptop drive will be harder.

 

I had considered using a fiber optic wire to redirect the light, but as it's on the front and the entire drive slides out when you press the eject button (it's quite a strange laptop drive) it wouldn't be practical. Quite strange really, all the other drives I've seen slide out fully but the lens and so on only slide out a little bit. With this teac drive from Kustom, the entire drive comes out of the housing when you eject it :/

[edit] Alright Zap my man, I'm going to ask for your help on this when I get round to it. Is that ok? I'm not worried about the soldering part, it's just getting the wires soldered to the right places. I have a decent digicam to take shots of the PCBs and so on. You think you could instruct me where to solder?

 

Sure, images will REALLY help.
(Use macro mode if you can)
Just send it to questions@zapwizard.com when you are ready.

 

ok.. i know this is an old topic but anyway...

i tried out this today.. and it worked.. sort of..

the primary activity led did work.. but my slave disc was stone dead... would'nt start at all... i tested and tested... tried about everything...

tested with a new cable... it worked fine.. but once i cut the 39th wire my secondary dies... (secondary dics is on the middle of the cable.. pri on the end)

i searced a bit on the net and found this:

http://support.gateway.com/s/CDROM/Mitsumi/CDR033AA/00000012.shtml

look at pin 39.. it says activity and something about slave... well.. it was my slave who died.... can this have anything to do with this??

right now i have a cable where the 39th cable is soldered in two spots.. you just gotta' love ghetto!

 

Interesting...
"Drive Active/Slave Psnt 39"

The schematic I have (Above), only uses pin39 for IDE activity.
It's not even wired anywhere else on the motherboard.
It was ripped directly from a MSI schematic, but so far has worked on ASUS, Soyo, MSI, and tons of others.

I am not sure how gateway could use that pin for slave detect as it is wired to both IDE connectors, unless it uses a data packet.

Are you trying this on a IDE Harddrive or CD-Rom?
This mod only works on harddrives.

 

well... i have two HDD's on the same cable... i cut the cable between the two discs....

the comp starts up because the master disc har the OS... but the slave don't start... i tried to switch the connectors around... master in the middle and slave on the end... bios don't even start to check for HDD's...

but when i solder the cables togeter again it works just fine..

i just can't get this to make sense..

 

I have some docs on interfacing to the IDE bus at home, and from memory theres a line you drive either high or low to select between the master/slave device. Could this posibly be this line and be causing probs? I dont have the stuff to hand and am going on what i remember mind, so could be wrong, and it was referring to an old school interface so maybe things have changed somewhat. Just a thought...

 

mabye.. remember that this comp. is pretty old... it's a cyrix 200MHz.... Asus mobo... 2 and 8 gig drives....

 

I had this problem when I set up my independent HDD leds...

I just noticed someones post at the bottom looking it up and have pointed them to the first post in my thread where point 2 discusses the problem I had with the slave.

 

I made this mod a week ago but I accidentaly connected the +5v directly to pin 39 of the HD.

Don't try this at home, because your HD led's won't work anymore. My LED just keeps burning now, something's burned inside my HD is guess, but it still works except for the LED .

 

Try a bigger resistor...

You have got a resistor right?

 

Off course I have, but I use pin headers to connect everything too, so that I can easily switch leds, etc. I accidentaly connected the HD connector to the LED pin header, so the HD got 5v and a lot of ampères.

 

Ok I have tried this and it works, but it doesn't

When I connect a 4gig Western Digital Drive as master and a 6.4gig Western Digital Drive as slave it works fine.

However, those are just two old test HDD's, when I use the same cable on the same motherboard with my proper HDD's the BIOS does not detect the slave drive at all.
The 'proper' drives are a Maxtor 10gig connected as primary master, and a Western Digital 40gig connected as primary slave.

Nothing wrong with the jumper settings on these drives because the BIOS detects them fine with a un-modded cable.
And as I said above, the same modded cable on the same motherboard and the same IDE channel works 100% ok.

What is going on, does anyone have any ideas or has anyone had this problem before? It looks like the 40gig Western Digital Drive just doesn't like that cable or something

Oh and the motherboard I am using is an ABit KG7.

 

Ok an update after some swap-arounds and testing.

It would seem that Maxtor (I always had a hate thing for these drives and now I hate them even more) is what's causing the problem.

If I connect any of the other 2 Western Digital Drives as master to the 40gig Western Digital Drive then everything works OK.
Also, if I connect the Western Digital 40gig drive as master, and the Maxtor as slave, that too works OK

Taking a read through the problem that Enak had....
2. Having wired it up correctly the drives weren't detected on boot up. I solved this by setting the master drive jumpers to Master with non-ATA slave. I've figured that the activity line is also used between drives on the same cable to detect the presence of a slave... without this connection some drives will assume they are on their own and cause the drives to not work.

I have taken a look at the installation guide for the detailed jumper settings on Maxtor's website and there is no information there for a 'Master with non-ATA slave' configuration.

The Maxtor (POS) drive in question is model 31024H1.

Any suggestions (apart from throwing it out the window lol)

 

It seems that some drives use this wire to tell if they are a slave drive.

It seems to mostly happen with maxtor drives.
(All the drives in my system are Western Digital)

But I have done this successfully on quite a mixture of brands.
In the end this modification may not work for your drive configuration.

Can you seperate those drive drives onto difference IDE cables?