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Newsgroups: comp.sys.nsc.32k
Subject: Re: Running without an FPU
Message-ID: <9009180129.AA00655@virtech.UUCP>
Date: 18 Sep 90 01:29:19 GMT
References: <<9009180017.AA19520@Shiva.COM>>
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Bert:

> I've had to struggle a bit, but I've managed to get MINIX up on my pc532
> without an FPU. Some of the problems I encountered are:
> 
> * The ROM needed a fix to get RUN and STEP to work.
> * MINIX saves FPU registers on a task switch
> * _begsig also saves FPU registers, causing any process which intercepts
>   signals to dump core.
> * GCC uses floating point operations in global-alloc.c

ARGHHH!!!!!

> So far I've been able to fix these problems in an ad-hoc manner, but I'd 
> like to co-ordinate efforts with other FPU-less pc532 owners (if there are
> any).

Please post your changes!!!  I'll also be happy to help once I get my
to-be-FPU-less PC532 constructed.  (nearly finished)

> I have several questions for the NS32K wizards out there:
> 
> 1) Is there some way to reliably detect the physical presence or absence 
>    of an FPU?

yes, if the machine hangs on the setcfg instruction, you can be sure that
you don't have an FPU :-)

how about a jumper?

... etc.

(I consider my PC-532 to be "fpu-*FREE*" !)