8 Apr
2003
8 Apr
'03
10:19 a.m.
At 10:47 PM 4/7/03 -0700, Don wrote:
All that means is the drive is capable of handling RLL encoding
(basically, it can correctly reproduce pulses at half-multiples of the
MFM spacing (although they won't ever be closer together than
the MFM encoder would produce). Such a drive will, of course, work
correctly with an MFM controller, but will have a lower capacity when so
used (in this case 21 Mbytes).
Remember that with the ST506/ST412 interface, it's the _controller_, not
the drive that handles the data encoding/decoding. The 'data cable'
carries the raw data stream to/from the disk.
-tony
Interesting question is whether it is being used as a 21mb MFM
drive or as a 33mb RLL. My guess would be 21mb.
It's an RLL drive and is 32 Mb according to my sources.