7 Dec
2010
7 Dec
'10
2:27 p.m.
On 7 Dec 2010 at 19:40, Tony Duell wrote:
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.
--Chuck