uIEC/SD == AWESOME!

Well, the hardware interface is much the same (IEEE-488/HPIB/GPIB). But the command set is totally differnt. So it certainly won't just plug-n-play. IIRC, the CBM disk units are essentailly file-oriented. You send a command to open a file (including the file name), the drive unit contains the part of the OS that finds that file in the directory, finds where it's stored on the disk and so on. The HP drives work at a much lower level. The file system is managed by the host computer. The commands to the disk drive unit read/write bocks (essentially the same thign as sectors). It's up to the host to turn those into a file system. There are many, many, HPs that supported HPIB drives. There were, alas, 3 different command sets -- Amigo (the earliest one), CS/80 (Command Set 80) and SS/80 (Sub Set 80).Documentaiton for all of those should be on the web (try bitsavers or the Australian HP museum site for details). You could probaly find an HP150 or an HP9000/200 machine fairly easily on E-bay. Now I don;'t know the exact details, but I read (I think on one of the HP9845 pages) that somebody had written an HP drive simulator programs for PCs fitted with an HPIB card (I believe said program has source available if you want to look for hints on the command set, etc). But one thing that this weg page siad was that it couldn't run with a 9914-based HPIB card, since HP did something that was essentially against the standard and which the 9914 couldn';t do. I do know that HP used the 9914 in their computers quite a bit, but that the drives used the Intel 8291. Of course if you're planning on bit-banging the HPIB protocol on the pins of a microcontroller (I think you need a little external logic, there is one transition where you can't take arbitrarily long to change one of the signals), then this won;'t be a problem. -tony