TRANSMITTING SYSTEM OF PLANT INFORMATION

摘要

PURPOSE:To realize the fetching the process signal of a high frequency and a high-speed transmission of the plant information, by providing a processor exclusive for transmission and a memory exclusive for transmission at a transmission control part of a local station, and reducing a load of a main processor. CONSTITUTION:A plant information transmitting system comprises a master station MS and plural local stations LS which are connected to each other via the party lines. A transfer data is transmitted and received between the stations MS and LS in a DMA transfer mode via a processor 17 and a memory 18 exclusive for transmission provided at a transmission control part 8 within the LS plus the MS. Accordingly the DMA transfer is possible regardless of the execution or nonexecution of an input/output instruction through a main processor 7 to an input/output part 10. Thus a high-speed transfer of data is possible with no queuing time required. In addition, the processor 7 is reduced for its load since the processor 17 performs an arithmetic of address comparison between the MS and the LS, and then a complicated input/output process is possible for the process signal. Thus the processing performance can be greatly increased for the plant information transmitting system.