22 Dec
2005
22 Dec
'05
6:30 p.m.
On 12/22/2005 at 6:10 PM a.carlini at ntlworld.com wrote:
That sounds like it would tell you the sector size and
the sector
numbers, but I read Tony's question as meaning "how can I tell
that immediately after the index hole there is sector #1,
followed by sector #2 etc." i.e. how can you determine the
sector layout?
Easy - first do a read of a non-existent sector--on a 765, the operation
will time out after seeing the index hole go around twice. So, now you
know that you're positioned right at the index hole (actually the leading
edge). Issue a bunch of Read IDs until you get the same ID twice. Do the
whole thing again to make sure.
What this won't get you are (a) sectors with no IDAM and (b) it won't tell
you if you're missing a sector (lost in the PLL sync up "blind spot") and
(c) if the same sector number occurs twice on the track.
But it's good enough for casual hobbyist-type work.
Cheers,
Chuck