| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a data communication system that can surely detect collision of data on a communication path without the use of an dedicated hardware. SOLUTION: A navigation device 2 adds collision detection data to a head of a frame at the transmission of a frame. Specific contents are set to the collision detection data by each device connected to a bus 5, and on the occurrence of two frames or over on the bus 5, the contents are destroyed without fail. A frame collision discrimination section 68 corresponding to a data transmission source compares added data actually sent/received on the bus 5 with additional data corresponding to its own device to detect collision of frames on the bus 5 in the case of dissidence. The frame collision discrimination section 86 corresponding to the data transmission destination compares additional data corresponding to each device connected to the bus 5 with additional data actually sent/received on the bus 5 to detect collision of frames on the bus 5 when they are dissident.</p> |
