| 摘要 |
<p>A control system for transferring messages between a programmable logic controller (21) and a host computer (25) over an Ethernet communications network (23) is disclosed. The messages include a routing address specifying an originating drop number and a destination drop number and a routing drop number. The system is responsive to the routing address for transferring the messages between the programmable logic controller (21) and the host computer (25).</p> |
