Cycle time Section 1-6
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1-6 Cycle time
All processes in the Trajexia system are based on the cycle time. The cycle
time is divided into four CPU tasks:
•250 µs time intervals for a SERVO_PERIOD of 0.5 and 1.0 ms
•500 µs time intervals for a SERVO_PERIOD of 2.0 ms
• 1 ms time intervals for a SERVO_PERIOD of 4.0 ms
The processes that can be carried out in each time interval depends on the
SERVO_PERIOD that is set.
The operations executed in each CPU task are:
1-6-1 Servo period
The SERVO_PERIOD can be set at 0.5, 1, 2 or 4 ms. The processes that take
place within the cycle time depend on the setting of the SERVO_PERIOD
parameter. The SERVO_PERIOD parameter is a Trajexia parameter that must
be set according to the system configuration.
The factory setting is 1ms (SERVO_PERIOD=1000). A change is set only
after a restart of the CJ1W-MCH72.
CPU task Operation
First CPU task Motion Sequence
Low priority process
Second CPU task High priority process
Third CPU task Motion Sequence (only if SERVO_PERIOD=0.5ms)
LED Update.
High priority process
Fourth CPU task External Communications
Cycle time = 1ms
250µs
1
2
3
4
Cycle time = 2 ms
500 µs
1
2
3
4
Cycle time = 4 ms
1 ms
1
2
3
4
Note The Motion sequence execution depends on setting of the SERVO_PERIOD parame-
ter.