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[STDS-802-16] Reed-Solomon example in 802.16 standard

Hi

I'm having a problem extracting the same results as the FEC example in
section 8.3.3.5 of the standard on page 444 using Xilinx IP block for RS
encoder. The first test vector refers to full bandwidth (16 subchannels)
using QPSK and overall coding rate 3/4. The RS code you use is
(40,36,2). According to the test vectors, if the input to the RS coder
is "D4 BA A1 12 F2 74 96 30 27 D4 88 9C 96 E3 A9 52 B3 15 AB FD 92 53 07
32 C0 62 48 F0 19 22 E0 91 62 1A C1 00" (where the last 00 is added
manually as specified), the spec says the first 4 bytes of the parity
should "49 31 40 BF". However, I get "33 11 0A 51". I am definately
using the correct RS parameters, am zero pre-padding correctly and
believe I'm using the correct byte ordering (although I've tried just
about all permutation of bit and byte ordering I can think of). I have
also tried to encode the data using MATLAB "rsenc" fuction which is
giving a totally different answer. Has anyone else had this problem? Or
I am doing something insanely wrong here.

Thanks for the help!
AM