I have and idea. A wild one. Get a reading off a
floating pin using the ADC. Use the value as a seed.
And reseed the generator after certain iteration.
Sound like an idea. Floating pins do not provide a
stable value and their values are within a limited
range. But when you keep on reseeding a value things
get pretty wild. 

John

--- Tony Smith <ajsmith@rivernet.com.au> wrote:

> > > Look carefully, and I think you'll figure out
> that the functions on 
> > > the page referenced ARE implementations of
> Galois LFSRs.
> > > Particularly clever implementations thereof that
> don't look 
> > like they 
> > > contain nearly enough instructions do so ...
> > 
> > The page also contains a few others that look a
> bit dodgy. I 
> > was mainly aiming at the one at the top, that
> claims to 
> > rotate with carry and to output that as random
> (AFAICT).
> 
> 
> The problem with the rotate & carry routines is they
> repeat, eg after 65k
> operations (16 bit register).  Not that you'd notice
> in most cases.
> 
> Also think about how to seed the routine, a way to
> cause the routine to jump
> to a different spot in the sequence.  In other
> words, start the register at
> a number, not 0.  Like in old BASIC games, where
> RANDOMIZE TIMER was used to
> seed the routine.  (And it always gave the same
> sequence too for the same
> seed.)
> 
> A typical method is that the routine always runs,
> and when the user presses
> a button it outputs the current value in the
> sequence.  Ok for a dice
> rolling app, not so good for something that doesn't
> have any inputs.
> 
> Tony
> 
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