8 Dec
2010
8 Dec
'10
11:48 a.m.
On 7 Dec 2010 at 19:40, Tony Duell wrote:
The advantage of using the hardware error line from the drive (if you
can) is that iy doesn't require the drive to be formatted in a way that
the controller understands.
-tony
I seem to remember that some/most/all
ST412-interfaced drives will
assert an error signal if you select a head that isn't present (e.g.
selecting head 6 on a 6-head (numbered 0 to 5) drice) or if you seek
heyond the maximum cylinder. I've worked on several systems that use
this to make sure the hard drive is the one they're xonfigured for and
complain if it isn't (even it it haas more heads/cyliunders than are
expected).
What most PC controllers return for a non-existent head is either
"time out" or "sector not found"--and that seems to work.