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Re: CYGNUM_HAL_RTC_PERIOD / floating point


Jonathan Larmour <jifl@eCosCentric.com> writes:

> David N. Welton wrote:
> > Jonathan Larmour <jifl@eCosCentric.com> writes:
> >>386DX? 386SX has no FPU. Does FPU work outside of cyg_start in threads?
> > This machine is a - what's the term you folks use ? - "bog standard"
> > modern desktop PC.

> It should say the processor model when you boot, I'd hope.

It's a PIII, and no, I don't have any of the Pentium stuff turned on
in the conf file.

>  >  I thought of trying it in a variety of places in
> > the code, and it doesn't seem to work in threads, either.
> > When I run it under bochs with debug logs turned on, it tells me:
> > 00005904485d[CPU  ] exception(07 h)
> > 00005904485d[CPU  ] interrupt(): vector = 7, INT = 0, EXT = 1
> > 00005904485d[CPU  ] int_trap_gate286(): INTERRUPT TO SAME PRIVILEGE

> And this is with the lazy FPU switching off even?

Yes.

> There should be no interrupt if the FPU is there and the lazy FPU
> switching is off. Unless you haven't got an FPU.

Hrm.  I'm stumped.  There is most certainly an FPU. I've double
checked everything by running it in the real PC instead of bochs, just
to be sure, but it doesn't do anything.

Infact, turning it off seems to generate a lot of the same message as
above, and the program no longer works.

Out of time for today... thankyou very much for your time.  Reading
this list has been a great learning experience.

-- 
David N. Welton
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