18 Jun
2008
18 Jun
'08
6:21 a.m.
The 279x (1,3,7) series chips actualy had a working pll data seperator.
Here is a link to the 279x controller chip data sheet:
http://retrotechnology.com/herbs_stuff/fdc_datasheet.pdf
As I recall, the 179x series chips could not reliably do sector reads from disks formated
on a 177x controller. The 179x could do a track read of the disk. Morrow provided a
program with the Disk Jocky controller which would do track reads, then write the track
back out creating a disk which worked well with either the 177x or 179x series
controllers. It was not a common issue, as very few people used single density once
double density became available, and new single density disks worked well with either
controller.
Les