Design a sequential function chart
Rockwell Automation Publication 1756-PM006I-EN-P - February 2018 39
Use logic to clear data
Let the controller automatically clear data
Each option requires you to make these decisions.
• Choose a last scan option.
• Based on the last scan option, develop your logic so that the last scan returns
data to the correct values.
On the last scan of each step, you have these options. The option that you choose
applies to all the steps in all the SFCs in this controller.
If you want to And on the last scan of a step Then see
Control which data to clear Execute only P and P0 actions and use them to clear the
required data.
Use the don’t scan option on page 40
Execute all actions and use either of these options to clear the
required data.
• Status bits of the step or action to condition logic
• P and P0 actions
Use the programmatic reset option on page 41
Let the controller clear data ---------------------------------------------> Use the automatic reset option on page 43
The following table compares the different options for handling the last scan of a
step.
Choose a last scan option