[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: >>questions

In article <1992Nov3.181609.15595@galileo.cc.rochester.edu> mh001b@uhura.cc.rochester.edu (Matthew W. Hacker) writes:
> 
> Thanks for tracking that down Dave.  I guess I just have to make
> that chunk of memory nonactive for the first xxseconds of the computer
> boot up time.

You can't tell when the IIgs is doing this scan - if the computer got
reset at a later point, you would have no way to tell - the RESET
signal doesn't go to the memory expansion connector.

Apart from hardware reset, it is feasible that a software reset could
be done (by forcing RAM disk resize on reset, invalidating the powerup
byte, and jumping indirect through $FFFC).

It just isn't safe to put something that 'looks like' memory in banks
$02-$7F, or you'll confuse the memory manager at some point.

You might have to use bank $80 or higher.  The memory manager will not
try to allocate memory past bank $7F.
-- 
David Empson

Internet: David.Empson@bbs.actrix.gen.nz    EMPSON_D@kosmos.wcc.govt.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand