Re: Why machine code is so much better....

From: C4D - Kim Madsen (kbm_at_components4developers.com)
Date: 01/19/05 

Date: Wed, 19 Jan 2005 22:32:03 +0100

Hi,

Assembler is actually a higher level language than machine code.... most often there is a one to one relation between
the assembler and the generated machine code, but not always.
And actually there (in most current CPU's) are even another layer underneath that, which people _could_ code in, but
tend not to...
microcode.
Many machine code instructions actually run small microcode programs containing multiple steps.
Thats by the way that the uP vendors have had a chance to correct some silicon and design bugs... by making alterations
to the microcode to circumvent a problem. Each time we start our PC's CPU specific microcode is loaded into the CPU from
the flash.
Hence its actually possible to make programs entirely in microcode if one chose to do so... not super practical, as the
microcode for an Intel processor is different from microcode from AMD etc.
In other words the machine code is an abstraction of the microcode, making it possible to run most applications on both
AMD and Intel CPU's etc.

But I bet you know all this already :) 

-- 
best regards
Kim Madsen
kbm@components4developers.com
www.components4developers.com
The best components for the best developers
kbmMW - kbmMemTable - kbmWABD - kbmX10

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