| From: | Frank Wille |
| Date: | 07 Aug 2000 at 23:35:00 |
| Subject: | Re: Questions |
Bo Simmons wrote:
> 3) LR Bug (can only happen
> > for 233 MHz machines, in this case install the bugfix on Aminet)
>
> 233MHz 604 machines or all 233MHz PPC?
AFAIK only 604e/233 CPUs, because Phase5 used the old CyberstormPPC
board, which was only designed for the heat of 200MHz CPUs.
> I had a lot of problems when
> running my 603e@233MHz, but also now at 240MHz... how do I see if
> the LR bug is present on my computer? And what does the bug do?
The LR bug sets one of the two most significant bits in the LR
register (PPC bit 0 or 1), the rest of the register remains intact.
On a Cyberstorm system the Fast-RAM always resides at 0x08000000-
0x0fffffff, so it's easy to detect the problem, because the first
digit of LR will be different from '0' ('8' or '4' in most cases).
I don't know where Fast-RAM is on a BlizzardPPC, but I heard about
strange areas like 0x60000000 or something like that? This is more
difficult to detect, and maybe this is also the reason it doesn't
happen with BPPCs - the bit is already set! :)