Emerson EZMotion User Manual page 165

programs. The user programs are assigned to tasks, and the tasks are handled in ascending order starting with task 0. If a
task has been assigned, but not initiated, then that task can be skipped. When the next interrupt occurs, the task is stopped,
and the process is repeated using the next available task. Once each task has been processed (depends on how many have
been assigned by the user), the whole process starts over at the first task. This process description is accurate as long as no
program is blocked. The following figure shows examples of user programs and task numbers and how the ezmotion
processes them.
Control Loop
User Program
Control Loop
User Program
Control Loop
User Program
Control Loop
User Program
Figure 159:
The following three figures are timing diagrams of a cyclic program with different utilization values (showing the effect) and a
user program initiated to run on a single task.
EZMotion User/Programming Guide
Revision A8
T0 T0
Update Rate
T0 T1
Update Rate
T0 T1
Update Rate
T0
T0
Update Rate
Diagram of User Programs with Multiple Tasks
www.controltechniques.com
Control Loop + User Program on one Task
T0 T0
Control Loop + User Programs on two Tasks
T0 T1
Control Loop + User Programs on three Tasks
T2 T0
Control Loop + User Programs on two large Tasks
T0 T1
T0 T0
T0 T1
T1 T2
T1 T0
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