I would think Herb would have some valuable input, but I do know with the SA800's there are a lot of jumpers, they vary based on the rev of the board, and you want to be sure that the loading of the heads is not jumper dependent. NOTING that I am only being logical not technical. I would only look to cross jumpering related to the drive head control off the list of possible causes. Bill On Thu, Aug 12, 2021 at 11:26 AM Jonathan Chapman via cctalk < cctalk at classiccmp.org> wrote: > Does anyone have experience running the MTI MXV22M? It's a dual-height > > QBus card that emulates RX02 but uses a 5.25" 96 TPI drive. I've got a > > small heap of them and we're trying to get them going. > > When trying to format diskettes using the process documented in the > > manual, the drive selects for maybe a second then deselects, and we get a > > drive not ready error. The controller isn't using the ready line, as the > > SA-460 for which it is designed doesn't supply it. No traces physically > > connect to pin 34. > > Since we're close to out of ideas, we've also plugged in a pair of Shugart > > SA-800s, on the idea that maybe the MXV22M is close enough to the MXV22 to > > show some signs of life. It doesn't give a drive not ready error, and it > > will step the heads like it's really formatting, but never loads the heads. > > Happy for any input on this one! > > Thanks, > > Jonathan