Re: [hatari-devel] move.w $ffff8908.w,d0 returns $ff in high byte?

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Miro Kropáček schrieb:

first I thought this is a clear bug but then looking into ioMem.c I see that this is deliberate? Is this how real hardware (STE in this case) behaves, i.e. that I can't read current DMA counter value as a word?

Just to clarify, I'd expect

move.w $ffff8908.w,d0

return d0.w = $00HH

See attachment for the result on a real STE. I don't think the data bus is actively driven for the high byte; so it's just "bus noise". Hence, Hatari's choice of 0xFF is as good as every byte.

Regards
Christian
--
Christian Zietz  -  CHZ-Soft  -  czietz@xxxxxxx
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