Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Introduction to Experiment 5Programmable PRNGDQenaDQenaD QenaD Qena0123addressdatawritereset24444488seedcoeffPRNG2outputclk loadPRNG 3..0PRNG 7..4coeff(7..4)="0000"10PRNG2outputcoeff(7..4)seed(7..4)seed(3..0)coeff(3..0)clk loadclk loadLinear Feedback Shift Register (LFSR) L, C(D) Connection polynomial, C(D)C(D) = 1 + c1D + c2D2 + . . . + cLDLLengthEach stage = D flip-flopInitial state[sL-1, sL-2, . . . , s1, s0]LSFR recursion:sj = c1sj-1 c2sj-2 . . . cL-1sj-(L-1) cLsj-L for j LSj-1Sj-2Sj-(L-1)Sj-L 4, 1+D+D4Connection polynomial, C(D)LengthExample of LFSRc1=1 c2=0c3=0c4=1C(D) = 1 + 1D + 0D2 + 0D3 + 1D4LFSR State Sequences4 = c1s3 c2s2 c3s1 c4s0 = s3 s0
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