6 Feb
2000
6 Feb
'00
10:19 a.m.
In RT-11, full MSCP support post-dates even 5.1. 5.1
works with RQDX1/2,
but not RQDX3, for example; because whoever wrote the DU: handler ignored
the MSCP documentation and made an unwarranted assumption about the
contents of the SA register during initialisation. It took me ages to
trace the problem and fix it :-).
MSCP support was added in V5.0 -- but there were some problems, not
the least of which was the fact that it setup the interface such that
if you didn't do any disk access for a minute, the disk would go off
line. This was corrected in a patch for V5.0 and in the distributed
V5.1, at which time it also worked with RQDX2... support for RQDX3
and other similar interfaces wasn't out until V5.2...
Megan Gentry
Former RT-11 Developer
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| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
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