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Altera_Forum
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15 years ago

Do you use LPMs for your LFSRs?

I want to implement an LFSR as a means of generating random numbers but I'm not sure whether to use an LPM or just code it in a process. I would be interested to hear how you choose to implement them...
Altera_Forum's avatar
Altera_Forum
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15 years ago

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It seems that the output sticks at whatever value I set the seed to be, i.e. a seed of 1111 resuts in a constant output of 15.

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The design is showing a perfect LFSR sequence of length 15 in simulation. I guess you missed to release the reset signal - or supplied no clock.

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according to xilinx doc a 4 bit shift register should have taps at 3,4

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This is a different form of the same sequence.