On Fri, 22 Oct 2010 08:25:17 +1000, David Eather
wrote:
On 22/10/2010 8:23 AM, Jim Thompson wrote:
On Fri, 22 Oct 2010 07:54:13 +1000, David
wrote:
On 21/10/2010 7:34 AM, Jim Thompson wrote:
I'd like to conjure up a random bit generator.
Just feed it a clock and have it generate random bits.
74HC... components preferred... I have most everything in that family
in my parts bin ;-)
Thanks!
...Jim Thompson
I posted some pages of Applied Cryptography he
http://www.filedropper.com/lfsr
The pages contain the information you need to build dozens of different
LFSR's of maximum period using a couple of 74... series. IIRC you can
replace the XOR function with NXOR and get a maximal period LSFR that
will self start (the all zero startup state becomes a valid state for
the LSFR)
Link times out :-(
...Jim Thompson
Send PM - I'll PM the zip file (0.5 Mb)
OK. Got it working. Repeats at 255.
What was confusing me was the double-talk about numbering the
shift-register stages. Must be Physics majors who still have their
direction of current reversed ;-)
Thanks again, David!
...Jim Thompson
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