Bob Ammerman wrote:
>
> > PS. The preferred way to generate good psuedo random
> > numbers is to generate numbers between 0 and 255 (for
> > eaxample) and place in a 256 unit lookup table where
> > there is only ONE of each number, but the postions
> > are random. Then you can read 256 random numbers
> > in sequence and have perfect weighting.
>
> This is really unneeded.
>
> A well designed PRNG (say one based on a shift register with feedback) _
> will, _by its very design_, generate every possible code in its range.
>
> Bob Ammerman


Hi Bob, maybe I misunderstand you, but I still think
the point was valid. If you generate a random number
every time you update the pwm and the number is TRULY
random it could be a disaster. You could generate the
same number every time for an unknown amount of times.
This is the real problem with truly random numbers.

A psuedo random system (like I suggested) cannot generate
the same number twice, nor can it generate the same
number at all until all possible numbers have been read.
This gives an equal weighting to all numbers IN ANY
GIVEN TIME PERIOD which is never achieved with a true
random number. A truly random system could generate
any number at any time, it could generate the same number
X times in a row and then not again for millions of
generations. Very bad if it is controlling your pwm. :o)
-Roman

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