Switch Case — Private/Subsystem Components

Switch Case

Control Systems / Ports And Subsystems

Chooses, each step, which one of the action subsystems it drives runs: the case whose values hold the input truncated toward zero, else the default output, else none. Simulink’s Switch Case block (BlockType=SwitchCase). Each subsystem it drives holds an Action Port; the library’s Subsystem Templates hold a ready-made Switch Case Action Subsystem.

Ports

• Inputs – one, a scalar.
• Outputs – one per case, and one more for default while Show default case is On. Each drives the Action input of one action subsystem.

Parameters

• Case conditions – a cell of 32-bit integers or integer vectors, one output each: {1,[2 3]}. {1} (default). No value may appear twice.
• Show default case – On (default) gives the default output.

Notes

• Each output drives exactly one action subsystem, through its Action input. The port counts are checked against the parameters before a run, by name.
• It runs: each step the input is truncated toward zero, as Simulink does (−2.5 is −2, not −3), and the first case listing that value runs its subsystem; the default runs when none does and Show default case is On. NaN runs the default. The input is one number; a vector is refused.

Code export

All ten targets. The generated code compares the input, truncated toward zero, with each case's values and writes 1 on the output it chooses and 0 on the rest; NaN and anything past the cases reach the default. VHDL, Verilog, SystemVerilog and PLC-ST test the range of inputs a case value covers, which is exact in their fixed-point and LREAL carriers.

Simulink bridge

Both directions, as simulink/Ports & Subsystems/Switch Case. Case conditions goes to CaseConditions and Show default case to ShowDefaultCase (On and Off to on and off). No parameter carries a port count: Simulink derives the outputs from these two, and an import does the same. "Sampling Time (s)" goes to SampleTime, as on every block.