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from: ED BEROSET
date: 1997-12-28 07:00:00
subject: Re: Moving things in ASM

From: Ed Beroset 
Subject: Re: Moving things in ASM
At 01:45 12/27/97, you wrote:
>I agree this is a big problem for folx who do not understand the Intel
>architecture; I do personally think, however, that little-endian processors
>are more "natural" than big-endian ones, since the lowest order bits of any
>object, no matter what size, are stored in lower order bits in memory. 
Here's a quote from an article from December 1995 issue of the Proceedings
of the IEEE written by Stan Mazor, one of the Intel engineers involved with
the early microprocessors:
"Some have wondered why the addresses in the 8008 were stored 'backward'
with the little end first, e.g., the low order byte of a two byte address
is stored in the lower addressed memory location. I (regrettably) specified
this ordering as part of the JUMP instruction format in the spirit of
compatibility with the Datapoint 2200. Recall that their original processor
was bit serial; the addresses would be stored low to high bit in the
machine code (bit-backward). Other computer makers organize the addresses
with the 'big end' first. The lack of standardization has been a problem in
the industry."
The "Datapoint 2200" Mazor refers to was the calculator for which the 4004
(Intel's first CPU) was designed.  I think it's fascinating that "backwards
compatibility" was an Intel concern even for the 8008!
Ed
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