Andrew Warren wrote:
> Tony Smith <piclist@mit.edu> wrote:
> 
>> The problem with the rotate & carry routines is they repeat, eg after 65k
>> operations (16 bit register).
> 
> Tony:
> 
> That property is hardly unique to LFSRs.  Since pseudo-random number 
> generators are deterministic algorithms run on deterministic machines 
> with finite memory, they ALL repeat. 

Unless you are going to add in environmental noise, such as a noisy
diode or some other thing, you will be stuck with LFSRs or the like.

You can use more than one LFSR and do clever things by combining the
values in special ways, incrementing only one LFSR, or using one to
select how many values to skip in the other, etc.

They are still pseudorandom, though.

If all you are doing is choosing a color to display on a RGB LED, does
it really matter if it repeats?  Or how often?

--Michael
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