Should anyone in the future be looking for such a code: I eventually sampled the PN9 output of a Rohde & Schwarz SMIQ3 vector signal generator. The procedure was as follows:
- I defined a trigger output indicating the start of a new PN9 sequence,
- I used a parallel bus decode on an oscilloscope to sample the PRBS code as well as the trigger output,
- I captured a total of eight 511-bit sequences to ensure they were each time identical to each other (and they were).
So, the sequence I found is:
0,0,1,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,1,1,0,0,0,0,1,0,0,1,1,1,0,0,1,0,1,0,1,0,1,1,0,0,0,0,1,1,0,1,1,1,1,0,1,0,0,1,1,0,1,1,1,0,0,1,0,0,0,1,0,1,0,0,0,0,1,0,1,0,1,1,0,1,0,0,1,1,1,1,1,1,0,1,1,0,0,1,0,0,1,0,0,1,0,1,1,0,1,1,1,1,1,1,0,0,1,0,0,1,1,0,1,0,1,0,0,1,1,0,0,1,1,0,0,0,0,0,0,0,1,1,0,0,0,1,1,0,0,1,0,1,0,0,0,1,1,0,1,0,0,1,0,1,1,1,1,1,1,1,0,1,0,0,0,1,0,1,1,0,0,0,1,1,1,0,1,0,1,1,0,0,1,0,1,1,0,0,1,1,1,1,0,0,0,1,1,1,1,1,0,1,1,1,0,1,0,0,0,0,0,1,1,0,1,0,1,1,0,1,1,0,1,1,1,0,1,1,0,0,0,0,0,1,0,1,1,0,1,0,1,1,1,1,1,0,1,0,1,0,1,0,1,0,0,0,0,0,0,1,0,1,0,0,1,0,1,0,1,1,1,1,0,0,1,0,1,1,1,0,1,1,1,0,0,0,0,0,0,1,1,1,0,0,1,1,1,0,1,0,0,1,0,0,1,1,1,1,0,1,0,1,1,1,0,1,0,1,0,0,0,1,0,0,1,0,0,0,0,1,1,0,0,1,1,1,0,0,0,0,1,0,1,1,1,1,0,1,1,0,1,1,0,0,1,1,0,1,0,0,0,0,1,1,1,0,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,1,1,1,1,0,1,1,1,1,1,0,0,0,1,0,1,1,1,0,0,1,1,0,0,1,0,0,0,0,0,1,0,0,1,0,1,0,0,1,1,1,0,1,1,0,1,0,0,0,1,1,1,1,0,0,1,1,1,1,1,0,0,1,1,0,1,1,0,0,0,1,0,1,0,1,0,0,1,0,0,0,1,1,1,0,0,0,1,1,0,1,1,0,1,0,1,0,1,1,1,0,0,0,1,0,0,1,1,0,0,0,1,0
The found PN9 code features a maximum of 8 subsequent 0’s and a maximum of 9 subsequent 1’s.
Note that I show the code as individual bits, not hex codes. The reason is that the PN codes repeat themselves in 2^n-1 bits, so the PN9 code repeats itself in 2^9-1=511 bits. That does not translate nicely into a discrete number of hex codes. In other words, should you express, say, 10 subsequent PN9 sequences into HEX values, you do not see the HEX code repeating itself.