Hi I was told by Tony that the 5Meg Tandy ( Radio Shack ) drive box had a similar controller. The firmware seems to be identical to the WD1001. I've used the Tandy controller on my Olivetti M20 that also seems be identical to the WD1001. Both the Tandy and the Olivetti didn't use the interrupt and used polling instead. If this is compatible with what you need, you might look into either controller from a Olivetti M20 or Tandy. The Olivetti was almost identical to the WD1001 from schematics but the Tandy had the addition of some address decoding, buss termination and buffering that was not on the WD1001. All this can be bypassed or removed if needed( as I did ). Dwight PS I did find a WD1001 but I have another application that needs it so I'm afraid it is not available. I have seen these on eBay about ever 4 or so months. I see a Tandy controllers about ever 1 to 2 months. I've seen the same controller used on the 8Meg as well. You need to look for the box with the typical MF connectors on the back. This model has the controller built in. The newer units used a controller in the TRS box and just had the drive and supply in the box. Easily distinguished by the connectors. Dwight _________________________________________________________________ Watch ?Cause Effect,? a show about real people making a real difference. http://im.live.com/Messenger/IM/MTV/?source=text_watchcause