Andre Nuendel wrote:
> 
> My LCII is now working with the card, but only if I switch off the cache.
> (The former problem was that the Extensions Manager switched off the
> Memory Control Panel  --> 24 bit addressing, my fault.)

Doh! :-)
 
> When I boot into NetBSD with the cache switched on I get this messages:
> 
> [snip]
> 
> fpu0 at mainbus (emulator)
> Data modified at freelist word 0 of object 0x6b95a00 size 164 previous
> 	type free (0x0 != 0xdeadbeef)
> [snip]
> 
> root file system type: ffs
> trap: type 0x3, code 0x0, v 0x0
> kernel: zero divide trap
> pid = 0, pc = 00056DFE, ps = 2002, sfc = 1, dfc = 1

I've gotten similar errors when I played with the writeback portion of my
IIci's Daystar PowerCache accelerator.  I think that something isn't
getting flushed at the right spot.

> Are these messages (and debugger messages) logged somewhere? I looked
> around, but couldn't find them.

No, sorry.  The machine is usually hosed at this point.  Outputting to
disk risks serious filesystem damage and further screwing things up.

> Is there any use in trying to get the cache to work?

Maybe.  You basically need to figure out how to flush the external cache,
and then put the necessary glue in locore.s to do this at the appropriate
times.  Do you know if this is a physically or virtually addressed cache?
If the former, it should almost "just work".  If the latter....ewwww...
that'd be a pain :-)  Anyway, unless you can get some documentation on the
card, it might take some disassembly of the card's control panel.

Later.

-- 
Colin Wood                                 cwood@ichips.intel.com
Component Design Engineer - MD6                 Intel Corporation
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I speak only on my own behalf, not for my employer.