Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 130

Number of Active Steps Register
This register is a device or label in which the number of active steps of a block is to be stored.
The number of active steps stored in the number of active steps register includes the following steps.
• Normal active step
• Coil HOLD step [SC] that holds the operation
• Operation HOLD step (with transition check) [ST] that holds the operation
• Operation HOLD step (without transition check) [SE] that holds the operation
• Steps that stop each operation
■ Precautions
• When a block ends, the number of active steps register becomes 0.
• The register does not become 0 when the SFC program ends but becomes 0 when the program starts.
8 SFC PROGRAM
128
8.4 SFC Information Devices