crb@raybed2.UUCP (CHRIS BURTTON) (03/09/88)
I would like to hook up an external 3.5" and 5.25" disk drives. Does anyone know where I can get the information to do so? Thanks, Chris Burton ..!linus!rayssd!raybed2!crb
tomb@hplsla.HP.COM ( Tom Bruhns) (03/12/88)
> I would like to hook up an external 3.5" and 5.25" disk > drives. Does anyone know where I can get the information > to do so? > > Thanks, > Chris Burton > ..!linus!rayssd!raybed2!crb > ---------- Info for doing this is available on at least some bulletin boards. I have downloded two separate articles, one for 3.5" and one for 5.25", from QUESTOR and ALINK in the Edmonds /Everett, WA area. The circuits are very simple, and very similar. The main difference is that the 5.25" replys with hex 55555555 and the 3.5" with hex ffffffff when queried for id, per the hardware reference manual. I have built the ckt for the 5.25", and plan to add 2x 3.5" when I can get the drives at a good price. They will share a common intfc ckt. One comment: I found that my Fujitsu 5.25 drive didn't like the fact that the Amiga holds the step direction line for only a hundred microseconds or so after a step command. I had to add a latch to hold the direction line for about 4 millisec. Other drives I have info for indicate it shouldn't be a problem for them. If you can't find the files describing the hw, I could be enticed to copy them onto a disc you supply and send it back in a SASE. The files include some IFF schematic pictures as well as narrative descriptions. Tom Bruhns HP-Lake Stevens Instrument Division 8600 Soper Hill Road -- MS60 Everett, WA 98205-1298 (206)335-2629