Pseudo-Random Binary Sequence (PRBS) by a Linear-Feedback Shift Register (LFSR) with a (2N-1) Period

Brief User' Guide

  • Set N (defaut N=8), the number of stages in the register
  • Click "Find Coefficients" button will cause the applet to find a set of feedback coefficients
    • The set of coefficient correspond to a primitive polynomial. However, there may be other valid sets.
    • The user can decide to enter his own set of coefficients by
      • Check "Coefficients Editable"
      • Enter "c5 c2 ..." as the customized values in the text area for coefficients.
  • Enter a initial bit sequence which has exactly N [0/1] values under "Initial data vector"
  • Enter an integer under "Sequence length i_max"
  • Enter a value, Nw, for "Displayed width". The output will be rendered in lines of Nw values
  • Click "Simulate" button to see a bit sequence at the register's output (right-most stage)
  • Read result in the text area window, which is also presented in a plot below
  • The plot can be zoomed in by dragging the mouse to form a rectange, and the region will be updated to fill the whole plot. A click on the "fill" button cause the plot to resume its initial scale.

Reference

Paul H. Bardell, William H. McAnney, and Jacob Savir, "Built-In Test for VLSI: Pseudorandom Techniques", John Wiley & Sons, New York, 1987.

Copyright © 2000 - 2011 EE Circle Solutions. All rights reserved.