| Re: [hatari-devel] Small test to run on STE |
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On 12 Feb 2012 at 12:11, Nicolas Pomarède wrote:
> > I'm wondering if the video address on STE is masked depending on the RAM
> > size ; could someone with an STE runs this small program and tell me the
> > result of D0 and D1 (you need to be in supervisor mode) :
> >
> > stop $2300
> > stop $2300
> > move.b $ff8205,d0
> > move.b #$ff,$ff8205
> > move.b $ff8205,d1
> > move.b d0,$ff8205
> >
> > This will briefly modify the video address high byte and restore it.
> > But I'm wondering if you will read $ff after writing it to $ff8205, or
> > if it will be masked depending on the max size of 4 MB (and you would
> > read $03 for example).
> >
> Ping :)
>
> Anyone with an STE that would be able to run this small test from devpac
> or another asm ?
>
I wrapped it in some C code (I don't have Devpac on my STe) and ran it. It
returned a value of $3f. It's a 1040STe with 4MB of memory.
If you need the source & executable I actually used, to verify I didn't make a
stupid mistake, let me know.
Roger Burrows