Re: [hatari-devel] Microwire register value on Falcon

[Laurent Sallafranque <laurent.sallafranque@xxxxxxx>]

Hi,

I'm totally OK for $ff8922 from your test program, but I'd like another 
test for $ff8924.w

You're testing the mask with $7ff (which is the "most common value".).

But what is the result for a $7ff0 mask ? (or any rolled value).
Does it still neg the value you entered and then neg it again, or does 
it return a fix $07ff anyway the value you give it ?

Regards

Laurent



Le 01/02/2012 23:56, Laurent Sallafranque a écrit :
> Another thought,
>
> Thomas, would it be possible to modifiy your bus error program to test :
> 1) is this address is a buss error one ?
> 2) if not, try to write a value into the address, then read it 2 or 3 
> times with some time between and repeat the write/read with a few 
> different values ?
>
> Like this, on the real Falcon, we could detect if some other addresses 
> behave like the microwire one.
>
> Regards
>
> Laurent
>
>
>
> Le 01/02/2012 23:52, Laurent Sallafranque a écrit :
> > Hi,
> >
> > Thanks a lot too for the tests.
> >
> > So, it seems that $ff8922 always return 0 and $ff8924 returns $7ff 
> > except the first time (a change, then the mask value).
> >
> > I think it could be OK to just return $7ff, but a program may test if 
> > the value is different and then equal.
> > As I've never encountered this before, I think we can just return 
> > $7ff and add a comment in iomemtabfalcon for this $f800 value, for 
> > later if needed.
> >
> > Thomas, instead of a return0 function, wouldn't it be better to have 
> > a returnFixValue (thevalue) one ?
> >
> > we could do : returnFixValue(0) for $ff8922 and returnFixValue($7ff) 
> > for $ff8924
> >
> > Regards
> >
> > Laurent
> >
> >
> >
> >
> >
> > 01/02/2012 22:09, Thomas Huth a écrit :
> > > Am Wed, 1 Feb 2012 20:45:06 +0000
> > > schrieb "Konador, Cyprian"<cyprian.konador@xxxxxx>:
> > > [...]
> > > > Below you can find result in TXT
> > > >
> > > > CPU - Microwire Data read:
> > > > pass 1    pass 2    pass 3    pass 4
> > > > $0000    $0000    $0000    $0000
> > > > $0000    $0000    $0000    $0000
> > > > $0000    $0000    $0000    $0000
> > > > $0000    $0000    $0000    $0000
> > > > [...]
> > > >
> > > > CPU - Microwire Mask read:
> > > > pass 1    pass 2    pass 3    pass 4
> > > > $f800    $f800    $f800    $f800
> > > > $07ff    $07ff    $07ff    $07ff
> > > > $07ff    $07ff    $07ff    $07ff
> > > > $07ff    $07ff    $07ff    $07ff
> > > > [...]
> > > Ok, thanks a lot to everybody involved for the fast help here! I'm not
> > > quite sure how to interpret the $f800 in the mask register here
> > > (anybody got an idea why the Falcon would return the inverted value
> > > here?), but I think for the most programs, it should be enough to 
> > > simply
> > > return the value that has been written to the register. What do you
> > > think?
> > >
> > >   Thomas