02-16-2018, 06:13 AM
I agree about the drive or power problem, but in both cases I eliminated those theories as I checked power while the drive was engaged and stepping, and used a logic probe to determine if trk0 is active and in both cases it is. I believe that this drive (1980 vintage) requires a nearly 20ms step rate when moving to random tracks - something the 8" drives can overcome by virtue that they require 24vdc to overcome inertia and seek times are not speced that low - 8ms track to track, but the r0, r1 values in the 17XX can be set for:
r1,r0 = head track-to-track stepping rates. (all)
r1 r0 1770/3 1772
0 0 6 ms 6 ms
0 1 12 ms 12 ms
1 0 20 ms 2 ms
1 1 30 ms 3 ms
so the SA8XX drive would have to use the 12ms. This BASF with a mere 12v stepper of not high specs says it needs 12ms track to track.
Not a show stopper because the SuperCard does what it is supposed to do. Just an observation, Jim. Appreciate your input.
W1ARQ Howard :-)
r1,r0 = head track-to-track stepping rates. (all)
r1 r0 1770/3 1772
0 0 6 ms 6 ms
0 1 12 ms 12 ms
1 0 20 ms 2 ms
1 1 30 ms 3 ms
so the SA8XX drive would have to use the 12ms. This BASF with a mere 12v stepper of not high specs says it needs 12ms track to track.
Not a show stopper because the SuperCard does what it is supposed to do. Just an observation, Jim. Appreciate your input.
W1ARQ Howard :-)