On 11/23/2017 07:02 PM, Paul Berger via cctalk wrote: > I have managed to get 2 PC type drives working in a 9122C they are two > different versions of the YE Data YD-702D. The important thing is the > drive needs to provide a ready signal, diskette change and density. > Most drives provide the last two but do not have a ready signal. You > also need to leave pin 1 unconnected this is a signal from the > controller to reset the diskette changed signal. One of the drive the > YD-702D-6037 can also be altered by moving jumpers to get power from the > cable. The other a YD-702D-6537D does not and it unfortunately seems to > be the more common drive. I changed the drives so that ready is on Pin > 34, diskette change on pin 2 and density on pin 4, the same as the Sony > drive in the 9122C. I did encounter one problem where if I tried to CAT > a diskette it would always report that the diskette was changed or > missing and I recall encountering this previously, it may be related to > how the diskette changed signal gets reset. On most "standard" 3.5" > drives the diskette changed signal gets reset as soon as the drive is > selected and receives a step pulse. On the Sony drives used in the 9122C > reset the diskette changed signal by a pulse on pin 1 from the > controller. What I think is happening is when media is changed, the > controller thinks it does not have to move the head so the diskette > changed never gets reset so the controller continues to think the > diskette has been changed, I will do more testing to verify. I thought > that booting with the drive empty provoked this but that is not the > case. I can post details of the modifications to the drives if anyone > is interested.
In cases like this, I fall back to my favorite--the Samsung SFD-321B: http://www.techtravels.org/wp-content/uploads/pefiles/SAMSUNG-SFD321B-070103.pdf Plenty of them in the wild and very configurable. In most of my cases, pin 34 is ready, pin 2 is Disk changed, DS0 is assumed and the spindle speed is 360 RPM. You can get them readily in black or white faceplates or even faceplate-less. FWIW, Chuck
