19 Dec
1997
19 Dec
'97
11:28 p.m.
I've tried
some random settings, and in most of them it comes
up to speed okay, selects, and then after about three seconds
starts a probably unhealthy wobbling, sounding as if it is rapidly
seeking a million different tracks, one after the other.
Microprocessor-controlled MFM drives of this era often do something
like this to reassure the microcode that everything is kosher. How
long does it do this for - seconds, minutes, forever? In
at least one setting, it doesn't always recognize when it has
got up to speed, and continues ramping up to a frightening pitch.
Y'know, at least some of the jumpers are for "factory use only". I'll
bet this is one. With the jumpers set as they were in the XT, it
selects okay,
but I get error messages any time I try to read, write, or
format the thing. It still works okay in the XT though.
Can you do writes in the XT?
Have you tried DS0, in addition to the DS1 that the XT disk controller+cable
is undoubtedly insisting on? Are you using a straight-through 34-line
cable on the S/09, like a sane disk controller design would insist on?
Or are you using one of those hokey twist-in-the-middle PC-clone cable?
Tim. (shoppa(a)triumf.ca)
Jason D.