> What I've done in the past, is to implement something like a 24 bit 
> LFSR, and only use 8 bits of it.
> So, you get the advantage that the next state is not readily apparent 
> from the current state.
> You don't have to take the 8 bits from the same byte either, and you 
> can invert some of them, or even use an LUT to translate them to 
> something else entirely, so that the left-shifting isn't apparent.

When you use the LFSR properly (shift at least the same number of steps
as you take bits) the shifting will not be visible.

Wouter van Ooijen

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Van Ooijen Technische Informatica: www.voti.nl
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docent Hogeschool van Utrecht: www.voti.nl/hvu
 

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