[Info-vax] OT: For MAC Lovers Only :-)

[JF Mezei]

On 12-10-16 15:51, glen herrmannsfeldt wrote:

> No, the "read track" command, at least for the WD controllers,
> isn't that useful. You don't know where the sectors start!

Touché. I was erroneously  thinking "block" when reading "track".

Is it fair to state that sector = block in most cases ?

> I am not sure by now that Apple was first to use it, but at least
> first to popularize it. The format is pretty much the same as
> the Apple II format.

In Steve Job's biography, this is discussed.  Apple was first and it was
a brand new product and disk format that Sony was working on when Apple
was talking to Sony and others. Turns out Jobs didn't want it, but some
Apple employees quitly kept the channels open with Sony so that when
Jobs' idea failed, they were able to go back to Sony and use their drives.


> The drives convert transitions (0 to 1 or 1 to 0) into magnetic
> flux reversals, and the opposite on read. (At least for the
> usual floppy drives and ST506 style hard drives.) All the
> timing is done by the controller, including precompensation.


But surely the controller would have come from Sony ?