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From: dewar@gnat.com (Robert Dewar)
Newsgroups: comp.lang.ada
Subject: Re: Bit_Order useful [was Query on portable bit extraction]
Date: 28 Oct 2001 17:23:19 -0800
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"Nick Roberts" <nickroberts@adaos.worldonline.co.uk> wrote in message news:<9rhlhr$u11j3$1@ID-25716.news.dfncis.de>...
> I know there are some big-endian machines (the more recent ones, perhaps)
> whose manufacturers' documentation number the LSB as 0 and the MSB as 31 or
> 63. 


This is highly confused if it happens. Bit numbering must
match byte ordering, or you get into a mess. The 68K
was notoriously messed up on this point (see the discussion
of this point in my book on microprocessors).

Certainly in Ada, the bit numbering should match the byte
ordering, or you will end up with non-contiguous fields
and a big mess.