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Re: [avr-gcc-list] Initilizing complex const arrays : syntax ?

From: Vincent Trouilliez
Subject: Re: [avr-gcc-list] Initilizing complex const arrays : syntax ?
Date: Mon, 19 Sep 2005 06:11:05 +0200

On Sun, 2005-09-18 at 21:24 -0500, David Kelly wrote:
> On Sep 18, 2005, at 7:58 PM, Vincent Trouilliez wrote:
> >
> > ...compiles and runs fine, but my scope timed it at no less than
> > 13ms !!!!  I am running on the on-chip 1MHz RC oscillator, so that's
> > about 13,000 machine cycles then, ouch !
> Shame on you for actually *measuring* something! You could have been  
> dumb and happy had you not measured!
> Possibly you now understand why I said earlier that I don't use printf 
> ()? I didn't measure execution time, years ago I waded thru the  
> source code of other embedded printf()'s. Too much stuff for my  
> embedded tastes.

Okay, I got your dot_two() working (the another_dot_two() has one last
fatal error that I can't figure out yet).

I tested it in all fairness. That is, I modified the printf hack from 

printf ("%d.%03d", x / 1000, x % 1000), to 
printf ("%d.%02d", x / 100, x % 100)

So that the functionality is the same as dot_two().

Doing this, printf doesn't take 13ms anymore, but 10ms.

And your dot_two() takes... 6ms ! That's a whole 40% faster, not bad
indeed !!! :o)


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