176461 User Manual.book

MicroLogix 1500 Programmable Controllers User Manual

RET - Return from Subroutine

Instruction Type: output

Table 21-5: Execution Time for the RET Instruction

True

0.44

µ s

When Rung Is:

False

0.00

µ s

The RET instruction marks the end of subroutine execution or the end of the subroutine file. It causes the controller to resume execution at the instruction following the JSR instruction, user interrupt, or user fault routine that caused this subroutine to execute.

SUS - Suspend

Instruction Type: output

Table 21-6: Execution Time for the SUS Instruction

True

0.66

µ s

When Rung Is:

False

0.00

µ s

The SUS instruction is used to trap and identify specific conditions for program debugging and system troubleshooting. This instruction causes the processor to enter the suspend idle mode causing all outputs to be de-energized. The suspend ID and the suspend file (program file number or subroutine file number identifying where the suspend instruction resides) are placed in the status file (S:7 and S:8).

The immediate data range for the suspend ID is from -32768 to 32767.

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