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Re: [f-cpu] random number generator
hello
Yann Guidon a écrit :
The simplest thing is a LFSR but it is not adapted
because the correllations between the bits might
miss faults. Something a bit more complex is needed,
look at the table-based methods. Given an initial
set of 2^n integers, it will generate good quality bit streams.
Now here comes the critical question (i have faced it
when writing the random initialisation in VHDL) :
do we need to reset the counter everytime or do we want
a new bitstream each time ? I have chosen the second
solution for the VHDL case because a "static"
bit generator can miss errors.
A solution that can be practical is to manage a small
"entropy file" (just like under Linux). It contains
the 2^n numbers, can be exported/imported as text
with VHDL functions, and is read during each simulation
startup. If a test fails, the table is not written back
to the file and we can track where the error is.
how does this idea sound ?
why not i will try something right now
the sentence "This package cannot be sold or distributed for profit."
is not compatible with "pure GNU" philosophy.
well, it's an *implementation*, and what you do is use it,
through a defined interface. so you can use it as you want as long
as you don't distribute it. You can mention in the source
that you have downloaded this library at this address,
so whoever doesn't have IEEE at home can use it.
ok no problem i will not use it
btw, i have found a way to use Simili 2.3 under windows :
i'll be able to look at your work but i won't have much resources
(PII 300MHz + 64MB) so i hope that your testbenches don't
require too much CPU time :-)
in fact, the benchmark will be portable : windows/linux/other...
YG
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--
~~ Gaetan ~~
http://www.xeberon.net
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