Since the development of first Programmable Controller, hereafter called as “PC”, in 1969, PCs have been growing up by computer and semiconductor technology and application needs from various industries.
However, in the last half of 1990's, changing of requirements to PCs have begun. Those requirements are higher degree of application needs, expansion of applicable fields such as process control, and economical system integration. In order to satisfy those requirements, improvements of functionality and performance of PCs with lower price are being accelerated.
Especially, expansion of PC's applicable field and use of network, improvements of functionality and performance, repletion of PC related equipment, down sizing, and adaptation to global trends are remarkable.