| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problems wherein conventionally, a memory data signal of a CPU of a main system is snooped and is acquired by a CPU of a subordinate system via a matching bus, using a parallel bus, which is thus unsuitable for long-distance transmission because the parallel bus vulnerable to noise is used, data to be snooped are the data to be stored in the main system, and thus the subordinate system cannot be processed simultaneously with the main system, causing delays and resulting at the cost of the response speed of the system as a whole, and a separate function for running a plant, without stopping it at updating of a program is required and which makes the functions complicated. <P>SOLUTION: In a duplexed control system, data to be snooped by a CPU2 of the subordinate system as a stand-by system from a CPU1 of the main system as an execution system are set as control information from a control target to be acquired by the CPU of the main system, and further, advantageously, the phase of a control period of the subordinate system is made to advance more than the phase of the control period of the main system. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
