Subject: Re: stability?
To: Colin Wood <cwood@ichips.intel.com>
From: Michael R Zucca <mrz5149@cs.rit.edu>
List: port-mac68k
Date: 08/07/1997 13:36:54
> That's a very good question, actually.  I don't really know the answer,
> though.  I thought that any use of the internal video automatically sucked
> up 1MB of RAM as VRAM.  However, I don't know how the mappings might
> differ between the two modes.

Well, if I recall from the last time I used a IIsi there was an option
in the Memory control panel or Monitors that allowed you to allocate
a certain amount of RAM to video.

> I use a NuBus video card, so this doesn't really effect me.  This could be
> a legitimate problem, tho, I guess.  As a IIci user, if there is anything
> I could do that would really help. please let me know.

I was thinkinbg at first that perhaps the kernel should be relocated at
memory outside of bank 0, kind of like when people turn up their cache
all the way in MacOS to make their programs run out of the other banks.

Nice idea but the jump table for all the interrupts is located way down
in low memory at around 0. You can't move those since that's where the
680x0 chips expect the interrupt jump table to be.

Oh well, just another bad design trade-off by Apple I guess.