Floppy drive track-0 issues

Hi guys, I've got a Citizen Z1DE-55A (3.5" 1.44MB PC) floppy drive hooked up to the disc analyser (it seems my Sony MPF520 has a duff head; it's reading garbage for one side of the disc). Here's the problem... - When the drive is selected, irrespective of head position, TRK00 is always inactive. - If the drive is given a seek command, it will seek to track 0, assert TRK00, but the INDEX and READ DATA outputs will go idle (float high). - The drive remains stuck in this state until power-cycled. Has anyone seen this kind of thing before? The MPF520 had a head-step lockout (if track0_sensor == active, then ignore STEP commands) but didn't crash out if you asked it to step. For what it's worth, the drive works fine in my PC... I just can't see why it's locking up like this. Also, am I right in thinking that pins 12 (DS1) and 16 (MOTEN) are the two I need to pull low to select the drive, if it's connected before the twist in the cable? And that DS0 and DS2 would be the select and motor enable pins (respectively) if the drive was located after the twist? Citizen are, as always, their usual "helpful" selves: "We don't make floppy drives, we never made floppy drives. LA-LA-LA, NOT LISTENING!" Thanks, -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/