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> Related question:
> what shall an ATAPI device do
> if the host doesn't restrict itself
> to the given byte count and
> reads or writes the data register
> too many times in PIO

Last time I saw this, the software responsible was writing 12 "word"s of command 
packet out rather than 12 "byte"s.  Whoops.

> The smart thing would be to terminate the command
> and report an error (which one?).

To talk about handling stuff that shouldn't happen, to believe I know what do I have 
to have a theory about why it did happen.

For Pio I guess I think of this as a special case of how to respond to Pio r/w of the 
x1F0 Data register at times when DRQ is clear.

Personally I like to see xD0D0 read when DRQ is clear but BSY is set i.e. two copies 
of the status register.  Mostly I like to see this because I hear it's popular - 
whenever I do see xD0D0 in data, I guess that's what happened.

I don't know that I have an opinion about what writes, nor about reads when BSY:DRQ = 
0:0.

Pat LaVarre

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