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#1383
Originally Posted by pichlo View Post
Not necessarily. Substituting x for "same as previous", 11111 can be transcoded as:
  • 1,1,1,1,1
  • 1,x,x,x,x
  • 1,x,1,x,1
The same for a line of zeroes of course
Ah, well, the document I'd read (although extremely weak on specifics, sadly) seemed to indicate that the B&O protocol demanded that there never be a consecutive pair of 0s or of 1s. But I don't recall it demanding that there never be a consecutive pair of the third value...

Still, as you say, that would be logical, if there were any value in never seeing consecutive values. (I still don't really understand how beneficial that is; these particular values are "space encoded", meaning that they are sent by turning on the LED for a fixed amount of time, and then turning it off for a variable amount of time. If I recall correctly, a 0 is the shortest off-time, a 1 is the longest off-time, and the third value has a duration between the 0 and 1 times. You can't really get away without having some timing mechanism on either end, I think...)
 

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