A while back I was trying to bruteforce a remote control which sent a 12 bit binary ‘key’.
The device I made worked, but was very slow as it was trying every combination at about 50 bits per second (4096 codes = 49152 bits = ~16 minutes)
I opened the receiver and found it was using a shift register to check the codes and no delay was required between attempts. This meant that the receiver was simply looking at the last 12 bits to be received to see if they were a match to the key.
This meant that if the stream 111111111111000000000000 was sent through, it had effectively tried all of these codes.
111111111111 111111111110 111111111100 111111111000 111111110000 111111100000 111111000000 111110000000 111100000000 111000000000 110000000000 100000000000 000000000000 In this case, I have used 24 bits to try 13 12 bit combinations (>90% compression).
Does anyone know of an algorithm that could reduce my 49152 bits sent by taking advantage of this?
What you’re talking about is a de Bruijn sequence. If you don’t care about how it works, you just want the result, here it is.