| 摘要 |
<p>PURPOSE:To make the structure of an application program simple and to make program preparation easier by providing common memories for storing input and output values of connected remote I/O device and an I/O buffer to a central controller. CONSTITUTION:Common memories 12, 32, and 42 for storing input and output values from remote I/O devices 13, 33, and 43 respectively connected to a central and local controllers 1, 3, and 4 are provided in the controllers 1, 3, and 4 and output value data of the memories 12, 32, and 42 are respectively sent to the devices 13, 33, and 43 and, at the same time, input value data from the devices 13, 33, and 43 are written in the memories 12, 32, and 42. Therefore, the application program exclusively used for the central controller 1 which collectively controls the controllers 1, 3, and 4 can be prepared by taking into account the input and output value data of an I/O buffer in the center and the need of a local input-output interface process can be eliminated.</p> |
