In Ladder Diagram, the controller is a top organisational unit that typically consists of task and controller tags. There can be a single task or multiple tasks. All the tasks inside a controller are executed in parallel. There are two types of controller blocks available in Simulink® PLC Coder™:
PLC Controller Suite
PLC controller suite is a block hierarchy that models a simple complete Ladder Logic Controller structure whereas a PLC controller block consists of ladder semantics. The controller tags store the information of global variables such as DataType, Mapping type, Port, Address etc. The global variables defined for a ladder diagram form the input and output ports of the controller.