| 摘要 |
<p>In a remote control system having a transmitter (1) and a receiver (2), a rolling code (A) is ciphered to generate a ciphered rolling code by repeating, n times, an exclusive-OR operation on a constant code (X) in a rolling code table and the rolling code as well as a Maximum shift keying. A key code specific to each control system is used as a constant code (Xk) at the k-th exclusive-OR logic operation so that the k-th exclusive-OR logic operation becomes different from system to system resulting in different ciphering method for each system. The key code is set in an EEPROM (19) in the process of control system production so that the rolling code (A) may not be deciphered even by a design engineer as long as the key code is kept undisclosed. <IMAGE></p> |
