Rockwell Automation 193 Drives and Motion Accelerator Toolkit Quick Start - Manual (Page 84)

84 Rockwell Automation Publication IASIMP-QS019E-EN-P - August 2013
Chapter 4 Logic Configuration
The run sequence is initiated by a machine START command via the start logic in the R03_Control routine of
the application module. By default, the run sequence is initiated by placing a value of 1 in the RunSEQ[0] tag.
When the RunSEQ[0] tag is set to 1, the first step in the run sequence is executed, starting the run sequence.
Each of the rungs in the run sequence provides a placeholder where you can insert application-specific step logic.
The Run-sequence logic may include, for example, motion instructions, drive commands, and/or other
conditional diagnostic logic.
The move (MOV) instruction is a placeholder to advance the run sequence to the next step by incrementing the
RunSEQ[0] tag. Each step in the run sequence requires a unique value assigned in ascending order. The steps
typically increase by multiples of five or ten. By default, the run-sequence template steps 1…10…20…30, and so
on. Before moving to the next step, a predetermined condition must normally be met to make sure the current
step is complete.
First Run Sequential Step Example
This Widg-O-matic application code first-run step (RunSEQ[0] = 1) example includes a motion axis move
(MAM) instruction, an instruction error detection check, and an process complete (PC) check. Before the
MOV instruction indexes to the next sequence step (for example, value 5 into RunSEQ[0] tag), the PC check
must be met indicating that the move is complete. The instruction error detection check is used to detect a
module fault in the application, preventing the run sequence from inadvertently hanging on a step.