Rockwell Automation Allen-Bradley DriveLogix 5730, User Manual

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What is DriveLogix5730? 1-9
Each program has a main routine. This is the first routine to execute when
the controller triggers the associated task and calls the associated program.
Use logic, such as the Jump to Subroutine (JSR) instruction, to call other
routines.
You can also specify an optional program fault routine. The controller
executes this routine if it encounters an instruction-execution fault within
any of the routines in the associated program.
Selecting a System
Overhead Percentage The Controller Properties dialog lets you specify a percentage for system
overhead. This percentage specifies the percentage of controller time
(excluding the time for periodic tasks) that is devoted to communication and
background functions.
System overhead functions include:
•
communicating with programming and HMI devices (such as RSLogix
5000 software)
•
responding to messages
•
sending messages
The controller performs system overhead functions for up to 1 ms at a time.
If the controller completes the overhead functions in less than 1 ms, it
resumes the continuous task.
As the system overhead percentage increases, time allocated to executing
the continuous task decreases. If there are no communications for the
controller to manage, the controller uses the communications time to
1. View properties for the controller and select the Advanced