Which instructions are best for passing and receiving specific parameters in a routine?

The JSR (Jump to SubRoutine) and SBR (SubRoutine) instructions are specifically designed for invoking routines and managing the execution of those routines within a ControlLogix program. Using JSR, you can call a subroutine, allowing you to pass parameters to that subroutine. This ability to receive specific parameters makes these instructions particularly effective for modular program design, where you want to compartmentalize functionality and reuse code efficiently.

When a JSR instruction is executed, it saves the current state of execution, including the instruction pointer, enabling the subroutine to run with its own parameters and logic without disrupting the main program flow. The SBR instruction serves as the destination for this call, where the passed parameters can directly influence its operations. This design simplifies programming and enhances readability and maintainability, as related functionality can be grouped together within a subroutine.

Other options refer to instructions that serve different purposes. MCR and JMP instructions focus on enabling/disabling specific sections of a program or jumping to specific labels rather than handling parameters. CTU and CTD instructions relate to counting operations and do not pertain to routine management. Similarly, TON (Timer On Delay) and TOF (Timer Off Delay) instructions are used for timing operations, not