Ed Logg used morse code in his code as fraud protection. When other vendors would copy their ROM they would usually remove Atari copyright attribution. This was not something they would notice and it was used by Atari against them in court.

This was used in a game called Centipede. Ed worked on it together with Dona Bailey (one of the few female game programmers at that time).

.BYTE 2, 0BB, 5A, 30 (where 0 is dot and 1 is dash and nothing for a space)
.BYTE 5F, 0EE, 7D, 0A8 ; Morse code for "COPYRIGHT 1980 ATARI"