PROCESS INPUT/OUTPUT DEVICE

摘要

PROBLEM TO BE SOLVED: To enable flexible adaptation to the constitution of a process operation end and to flexibly cope with alterations of the constitution of the process operation end by providing an operation end drive module with a serial transmitting circuit for connecting with terminal board modules. SOLUTION: One or more PI/O's 3 are connected to a process controller 1 through a CPU bus 2. Further, each PI/O 3 consists of one operation end drive module 4 and one ore more operation board modules 6. The operation end drive module 4 and operation board modules 6 are connected by a serial transmission line 5. The terminal board modules 6 are connected to the process operation end 7. This PI/O system can be controlled by one operation end drive module by combining terminal board modules according to one group of process operation ends to be controlled, so interlocking between operation end drive modules is unnecessary.