| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent unrequired data input unrelated to an original message on a reception side by adding the index of a message length to a message to be transmitted, fetching a length portion equivalent to the index added to the message among the received message and abandoning the other part at the time of receiving the message. SOLUTION: The reception signals of an antenna 1 are demodulated in a demodulation circuit 2 and the demodulation signals are supplied to a control circuit 3. The control circuit 3 extracts the message from the demodulation signals and prepares the message for transmission to external equipment corresponding to a program inside a memory 4. The prepared message is modulated in a modulation circuit 5 and the modulation signals are transmitted from the antenna 7 to the outside together with power for an external equipment operation originated from a power driver 6. Communication is started by recognizing a header first, then the message length is recognized by reading the length, the contents of data are fetched for a prescribed length corresponding to the value of the length thereafter and the authenticity of the message is inspected by reading a check further.</p> |
