Control Techniques Epsilon EP-P Reference Manual page 131

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.
Control Loop
Cyclic Program
User Program
Figure 127:
Control Loop
Cyclic Program
User Program
Figure 128:
Control Loop
Cyclic Program
User Program
Figure 129:
Epsilon EP-P Drive Reference Manual
Revision A4
Cyclic Program Utilization
set to 80%
T0 T0
Update Rate
Cyclic Update = 3x Update Rate
Diagram of User Program and a Cyclic Program
Cyclic Program Utilization
set to 50%
T0 T0
Update Rate
Cyclic Update = 3x Update Rate
Diagram of User Program and a Cyclic Program
Cyclic Program Utilization
set to 40%
T0 T0
Update Rate
Cyclic Update = 3x Update Rate
Diagram of User Program and a Cyclic Program
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Control Loop + Cyclic Prog + User Prog on one Task. Cyclic
Program Utilization set to 80% means cyclic program is suspended
after 80% of update is reached, then resumed next update
T0
T0
Same as above except Cyclic Program Utilization is set to 50%
instead of 80%. Note that Cyclic Program takes an extra update rate
cycle to complete
T0 T0
Same as above except Cyclic Program Utilization is set to 40%. In
this scenario, Cyclic Program cannot complete within 3 updates and
so Overrun Error occurs in next update. Need less code in Cyclic
Prog, higher Utilization setting, or Larger Cyclic Update Rate setting
Overrun Error
T0
T0
T0 T0
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