Re: __LITTLE_ENDIAN vs. __LITTLE_ENDIAN_BITFIELD

[Krzysztof Halasa <khc@pm.waw.pl>]

Jeremy Fitzhardinge <jeremy@goop.org> writes:

> but the gist is that IBM has
> traditionally bit 0 for MSB and x for LSB.  It's a pain to work with:
> for one, bits in the same place in a word (say, control register) are
> renumbered in 32 vs 64.

I wasn't aware of that, but it doesn't really change the bit order,
only bit names (numbers actually). Extremely weird BTW but I guess
these things weren't that obvious to everyone some 50 years ago.

> And I've worked on at least one piece of
> hardware in which the hardware designer had a brain-fart and first board
> had bit 0 on the CPU wired to bit 0 on the northbridge - should have
> been 31 -> 0, 30 -> 1, etc...

I suspect the board wasn't able to run any OS, was it? :-)
Would make a real example of the different order of bits, though.
-- 
Krzysztof Halasa
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