On Thursday 07 June 2001 13:07, you wrote:
> Cool... And if so, I assume it must also be possible to use all address
> lines for I/O ports higher than 0xff?
>
Yes,
but you will get conflicts because all programs (including bios/basic etc)
made up until now assumed that the hardware would only use the lower 8-bits
and the value of the heighest 8-bits isn't used, so the programmers just
ignored whatever value that could be in register B. This would mean that your
16-bit i/o address could be trigerred by accident. You have to consider the
highest bit as containing "random" values.
David Heremans
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