| 摘要 |
<p>PURPOSE:To compare a check data previously created with a checked data created on the basis of a discriminating code, so that its fluctuation for whether provided or not can be known by whether both the data agree or not. CONSTITUTION:In a transmitter T, check data B0 to B3 previously produced from a check sum setting circuit 15 are output to an addition circuit part 13 of a CPU12. In the CPU12, the check data B0 to B3 are compared with a checked data created to be based on a transmission side ID code S read from an ID code memory 14. When both the data agree, an LED4 is lighted by the CPU12, simultaneously with feeding the transmission side ID code S to a decoder circuit 16, and next the code is converted into a modulation signal in a modulation circuit 18 and fed out by an infrared ray from a light emitting circuit 19. In the case of both the data not in agreement, since the LED is not lighted, voltage of a battery 17 is judged to drop. When door lock control is incapable even by lighting the LED, a transmitter T and a receiver R are judged in a trouble.</p> |
