>> What I'm really afraid of here is a known bug in the 68LC040 chip.
>> Apparently, the author of SoftwareFPU ran into this, and as a result,
>> SoftwareFPU doesn't work on 68LC040s. It's a known bug listed on Motorola's
>> errata sheet. As far as I know, there is no workaround.
>
>Hm, I downloaded 040 errata from Moto's web site, but it doesn't say
>anything of the kind...   Do you know, if it's on the Net, where I can
>find it?

Looks like Moto's trying to pull a fast one. The errata I saw on
www.mot.com don't list the bug either. You can download the SoftwareFPU
package for some limited info. I'll get back to you on this.

>
>> The nature of the bug is that the 68LC040 sometimes doesn't set the program
>> counter correctly when returning from an F-line exception. Normally, F-line
>> exceptions never return, so this isn't a problem.
>
>Not sure what you mean here.  F-line exception handler exits by RTE
>instruction, I think, and RTE means "ReTurn from Exception"...

Yep, as I remember, that's it... F-line exceptions can't be properly
returned from. Nobody noticed it because the MacOS just pops up a "Sorry, a
system error occurred. type 10 error" box.

Please don't ask too many technical questions of me... I program in C, not
680x0 assembly, and I'm just passing on details of this which I remember.
=) I know the basics of assembly language concepts, though, because I used
to do 65816 assembly.

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