Re: Byte Addressability And Beyond

According to Lawrence D'Oliveiro  <ldo@nz.invalid>:

On Wed, 1 May 2024 01:49:56 -0000 (UTC), John Levine wrote:
>

Until the PDP-11, all byte addressed machines were bigendian. Despite a
lot of looking, I have never found an explanation of why DEC made the
PDP-11 littlendian.

>
As I previously mentioned, little-endian just makes more sense.

I happened to be looking at Blaauw and Brooks "Computer Architecture"
published in 1997, which has several pages on bit and byte numbering.
After noting that the Big- and Little- names come from Gulliver's
Travels, they say on page 100:

 "Unlike Swift's, the computer Endian controversy is not pointless. The
 Little Endian design has many complications in use; we much prefer the
 Big Endian. Having two active conventions is very painful. Several
 recent Big Endian RISC computers, including the MIPS, the Motorola
 88000, and the Intel i860 provide a data-movement operation that can
 perform the Big Endian-Little Endian permutation. We predict that
 Little Endian addressing will die out, just as decimal addressing
 did."

Really, people like what they are used to. They were just wrong about
the i860 which was little endian, but had a mode bit to make data
addressing big endian.
--
Regards,
John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
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