31.15.3.6 System Variables Indicating Execution Results - RCL/RCLP

Program Example

RCL

  1. When a positive transition instruction turns ON, the RCL instruction is executed. When the RCL instruction is executed, the result from rotating 1 bit with carry over is stored in D1.

  2. When 1 bit is shifted to the left with carry over, you can use #L_CalcCarry to check the value of the most significant bit before the rotate operation.

    • When using a normally open instruction, the RCL instruction is always executed as long as the normally open bit is ON.

RCLP

The RCLP and RCL instructions have different ways of detecting when to execute. In the RCLP instruction, Even when using a normally open instruction, the RCLP instruction executes only when it detects the upward transition. Even if the bit of the normally open instruction remains ON, the RCLP instruction is executed only for one scan.