The first PC-based controller in 1986 was already high-performance because, thanks to fast PC processors, it was already significantly more powerful and faster than the so-called hardware controllers at that time. Even then it was a challenge to bring this computing power “down to the ground,” i.e. to the sensors and actuators of the plant to be controlled. Although plug-in I/O cards were a solution, they coupled the maximum number of inputs and outputs to the number of free card slots and led by nature to the multi-wire, inflexible wiring of all peripheral devices up to the PC in the central control cabinet. As a result, a serial fieldbus was required – and there was still no convincing system at the close of the 1980s: Interbus, SERCOS and co. were still in their infancy and initially supported either I/Os or drives. PROFIBUS DP and CANopen hadn’t even been invented yet. Beckhoff made a virtue out of necessity and developed the Lightbus protocol that was the basis for the current real-time Ethernet fieldbus: EtherCAT.
|PC-Control: EtherCAT: High-performance control requires high-performance communication||EN||2011年8月1日||0,56 MB|
|PC-Control: EtherCAT: High-Performance-Steuerung erfordert High-Performance-Kommunikation||DE||2011年8月1日||0,40 MB|