Each input or output instruction is assigned an address (shown below the instructions in Fig. 1, on page 22) indicating the location in the PLC memory where the state of that instruction is stored.

THE use of function blocks for programming of programmable logic controllers (PLCs) is gaining wider acceptance. Rather than the classic “contact and coil” representation of ladder diagram or relay ...

The differences among and preferences for Instruction List, Structured Text, Ladder Diagram, Function Block Diagram, and Sequential Function Chart PLC programming languages, as ...