From: Petr Stehlik <>
Date: Sat, 20 Jun 1998 08:22:12 +0100


I have asked Jiri Richter to make the 8/10 MB modification of ST-RAM and
so he did it. However the Falcon didn't boot. So then I finally have
looked into TOS 4.04 - and couldn't believe what I saw there. The TOS 4.04
is so "clever" that it does _not_ probe for size of ST-RAM (TOS 1.0 -
TOS 2.06 did probe and were able to find every 128 kB memory bank so
you could have 384 or 1280 kB on ST, for example).

So, according to Compendium's memory map Falcon can have 8 or 2 MB of
RAM (i.e. half of usual size) if you have connected an original Atari
monitor (SM124 or SC1224) instead of VGA or TV. Sounds strange? We will
have to get a better memory map of Falcon's HW registers, it seems. I am
especially interested in $FF800x registers. Don't you know somebody with
better informations about them, please?

But as the 14 MB limit of ST-RAM is _hardcoded_ in TOS, I would probably
have to _modify_ TOS to get 8 or 10 MB RAM (for NOVA and other users).
So this is yet another reason to buy PROM, change TOS and burn it there.

E-mail:                        PARCP developer
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Received on lø. juni 20 1998 - 11:32:00 CEST

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