Subject: Re: '040
To: None <>
From: Ken Nakata <>
List: macbsd-general
Date: 09/06/1994 09:43:13
   From: (grantham)
   Date: Mon, 5 Sep 1994 14:42:11 -36507155 (GMT-0800)
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   > > Just for clarification, are there any chance for MacBSD to run on
   > > machines that are currently supported, with an 040 accelerator?
   > > If it is the case, I might consider buying a 68LC040 accelerator
   > > (no, not 68040, I mean LC...)
   > There is a _chance_.  I wouldn't give it very high odds at this point,
   > though, as the '040 code is known to work only well enough to get me to
   > the SCSI bus probe.  As for the LC, I forget--is that the FPU-less?
   > How is it crippled?

   I think an LC has no FPU.  You'd basically be facing three issues:
	   1) the 68LC040 has no FPU.  If you take out the FP context
	    save and restore code in the kernel and used binaries compiled
	    with -msoft-float (or is it -f?), you might get by.

I mean, I want to use FPU-less accelerator for FPU emulator
development.  I can use my SE/30 while I'm writing the emulator and
test it with the accelerator, at least I thought.  But an 030
accelerator w/o FPU is better suited for that purpose, I guess.
Does anyone know a cheap 030 accelerator for SE/30?

	   2) Your accelerator may have on-board memory.  It probably uses
	    an extension in macOS to map that memory to logical 0, so it
	    looks like normal RAM.  MacBSD will not be compatible with this
	    because it does not know how to map that memory.  If it's just
	    a drop-in replacement board for the CPU, it would probably work
	    (barring cache issues), much like Mike's DayStar '030.
	   3) The '040 code in the kernel has not been thoroughly tested.

Okay, thanks for the clarification.