Use the inline variant blocks Manual Variant Source and Manual Variant Sink. The Manual Variant Source Block provides variation on the source of a signal. The block is a switch that can have two or more input ports and one output port. Each input port is associated with a variant choice. Only one input port is active during simulation. The active input port determines the active variant region. Similarly, the Manual Variant Sink block provides variation on the destination of a signal. The block can have two or more output ports and one input port. Only one output port can be active during simulation, and the blocks connected to that port determine the active variant.

Consider the slexVariantSourceAndSink model containing two Variant Source blocks Variant Source1 and Variant Source2, and a Variant Sink block. The variant conditions at the inports and the outports of the Variant Source and the Variant Sink blocks determine the activation and deactivation of the blocks connected to them. V and W are the variant control variables and are defined in the PostLoadFcn callback of the model.