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IDE drive swapping board

IDE drive swapping board

IDE drive swapping board

(OP)
Ok, this sounds a lot more complicated than it is....

I ended up with a crate of surplus standard Travelstar 20gig 2.5" hard drives.  I bought an external USB adapter that will allow one to be read via the 2.0 USB port.  Works great! Sets it up just like a normal drive, plug and play, all bells, whistles, yadda yadda.... cost 10$ at compusa

Currently, as one drive fills up, I unplug usb device,  pull drive out, put another in and go from there.  All well and good.

Here is where it gets interesting, if I built a box and a board that had say 25 2.5" sockets, tied all data lines together in series and had some logic set up to control some SS relays that would only power on one drive I wanted to use at the time would that be enough? Or would having non-powered up drives on the bus cause problems?   The logic would also power off the usb controller for a short period of time as well to give it time to reset itself.

I know its a lot of effort for little gain, but the "cool factor" gets me everytime :)

RE: IDE drive swapping board

Not an electronic engineer myself but your idea is just automating the hot swap of the USB 2 hard disks.  Thus in theory it should be OK but I don't see the real benefit.  By the time you hook up the 25 disks together and use them sequentially you will lose touch of which disk is holding what.

I think Firewire does allow you to daisy-chain a number of units together but Firewire need external power which you can get away with USB 2 internally powering a hard disk of only 20 Gb.

RE: IDE drive swapping board

As a general rule, connecting unpowered outputs to active outputs is a bad idea.  It's very likely that the unpowered output will look like a low impedance.  

On top of which, even it that wasn't a killer, 24 dead loads will probably choke the poor schmuck trying to drive the lines.  And these are output loads, not input, which is probably already 10 times worse.

TTFN

RE: IDE drive swapping board

(OP)
Ok, thanks for the input! It was just a thought. Not going to pursue it.



  

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