Sign-in / Sign-up
Your question

Reversing Ide Cable to reach between HD and DVD drives?

Tags:
  • Homebuilt
  • Cable
  • DVD Drives
  • Systems
Last response: in Systems
April 23, 2007 7:52:38 PM

I have tried googling this and am at a loss as to what is do-able. I have an 18'' IDE cable. I have a mid-tower and a MB with ONE IDE channel. Rather than frig with an IDE addon card or RAID controller card i just want to switch it around so that the MB connector is going to the DVD drive, the middle is still going to the storage IDE and the last plug is going to the motherboard.

Since that might not have been clear i will illustrate:

MB----------------------SL-----------MAster

I want to do this so I have the longer stretch of the cable to reach between my DVD drive and storage drive:

MAster------------------SL-----------MB

Can it be done without modifying the cable (i'm guessing no...) or is there a way to switch a few of the wires around to do so? I've found a few sites that show what each wire is but considering this is going to be connecting some important devices i'd rather not try things on my own.

Keep in mind i have no crimpers or other tools to do this, aside from a soldering gun and pliers.

More about : reversing ide cable reach dvd drives

a b B Homebuilt system
April 23, 2007 8:12:47 PM

I vote to just try it. As long as things are jumpered M/S, it might work. (i seem to remember doing this anyways once...) I don't understand why you need to do it however. Usually the drives are close to each other, and the motherboard farther away. You might need to move the optical drive and the harddrive closer together.

And when some noob comes in telling you to not hook up the optical and harddrive on the same IDE channel, inform him of Independant IDE timings.
April 23, 2007 8:25:36 PM

It should work. The only thing is you can not reverse the cable to drive connection (Look at the holes in the cable).
Related resources
April 23, 2007 8:36:39 PM

There are differences in the wiring on the connectors:

On the blue (controller) connector, pin 34 (CBLID-) is removed. This allows detection of the ATA-66 cable. Note that this signal is also called PDIAG- and is used to communicate self-test status from slave to master. On the gray (slave) connector, pin 28 (CSEL) is removed. This causes the drive to set itself as a slave if it is jumpered for cable select. The black (master) connector has no pins removed. This causes the drive to set itself as a master if it is jumpered for cable select.

My guess is it will not work properly as you will be sourcing pin 34 on the controller side.
April 23, 2007 8:37:31 PM

Yea I realize the plugs only fit one way, and no I can't really move the drives close enough together because it's a HD and a DVD drive, and my 3.5'' floppy bays won't take a hard drive in it without leaving the front bezel open. Seeing as how i special ordered a front bezel for my cd drive, i'm not just going to ignore it on the floppy bay.
April 23, 2007 8:38:45 PM

It will work with a 40 pin cable if all your devices support a 40 pin cable. It may not work on all 80 pin cables. Some 80 pin cables have conductors punched out. If your 80 pin cable does not have any holes in the ribbon, then it should work fine.

The only way to know is to try it.
April 23, 2007 9:04:54 PM

Quote:
I have tried googling this and am at a loss as to what is do-able. I have an 18'' IDE cable. I have a mid-tower and a MB with ONE IDE channel. Rather than frig with an IDE addon card or RAID controller card i just want to switch it around so that the MB connector is going to the DVD drive, the middle is still going to the storage IDE and the last plug is going to the motherboard.



Yes it will work no problems. Since the only difference is the "Cable select" missing pin (wire clipped to the connector) you'd have to use the jumpers to set the HD to master and the optical to slave.

IDE 40 and 80 wire cables use "Distributed impedance" of 1000 ohms. There is no requirement that the device used as Master be on the end of the cable, the only requirement is that the FIRST device must be on the end of the cable (As Master or Single) before a second one is connected to the middle connector, otherwise the unterminated end will cause reflections and distorted data.. And yes, you can actually use the cable backwards with the device end connected to the motherboard but again the Cable Select option can't be used.