Maxtor XT-2190

FWIW, the Seagate ST-4096 apparently used an unused pin in the data cable to place the drive in a Recovery Mode where the step and direction lines would then be used to microstep around the then current track. There are several unused or rarely used pins in the ST-506/412 interface that could have been repurposed to enable microstepping. AFAIK, there was no standard. Tom -----Original Message----- From: Tom Watson [mailto:tsw-cc at johana.com] Sent: Friday, January 23, 2015 7:58 PM To: cctech at classiccmp.org Subject: Re: Maxtor XT-2190 The discussion about servos on the XT2190 prompted me to turn on a machine (Altos ACS 68000) that I have with one of these nice drives in it.? The initial sounds of the drive is it re-calibrating using a stepping sequence.? This may be done by the drive controller to find track zero, or the drive itself (I really don't know).? Since the stepping (and subsequent servo lock) happens at a low frequency, it is the sound you hear.? Sometimes it takes a couple of times to get its act together, but it works well.? This was a machine that had been off for a bunch of years (over 10?) and it came back to life nicely.? I couldn't say much about the terminal I had attached as the dust that had accumulated made some keys not function so well, but I'll take some canned air and "blow it out" to get it working well. I note that the MFM interface does not have any "microstep" capability, only a simple step function.? I believe that the SMD interface did (it has been a few years, I never used it in my work), and the ESDI might (I never worked with that one). Soon I'll get the MFM drive simulator working and go "solid state".