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Altera_Forum's avatar
Altera_Forum
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17 years ago

What is the PRBS sequence

Hi. Could anybody tell me how to re-generate in Matlab/C the same PRBS 7 sequence used in the SIIGX_SI_Kit demos? The polynomial is X^7 + X^6 + 1. Thanks for the help!

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Is your question specifically how to implement the polynomial? This is typically done using shift registers (which you can fake in C). The exponents in the polynomial indicate which bits get XOR'd with the input bit.

    Jake
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Thank you for the reply.

    Before generating the sequence don't I have to know the seed as well? I can't find this information.

    I just want to know the exact PRBS generated by the demos
  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    Altera only provides .sof files. Is it possible to tell from these? Sorry, I am new to all this stuff and there is a lot of things I am just learning.

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    I was assuming, that HDL design files are available for the project. If this isn't the case, you have to find the seed from data analysis. But that's pretty easy, if the polynomial is known.

  • Altera_Forum's avatar
    Altera_Forum
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    17 years ago

    the PRBS sequence that you need is for single bus line? if this is the case, then you can set your seed to be 7'b1111111.