Lika H 58 Series, Руководство пользователя

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Hx58x EtherCAT®
Synchronous with SM3
In this mode data is sampled and then copied into Sync Manager buffer as soon
as previous data was read from the master (SM event); in this way new sampled
data is synchronous with master readings.
New data will be read by the master at next cycle (following SM3 event), so if
cycle time is too long, data could be relatively old for a real-time system.
The main advantage is that data is updated exactly when master is reading
(synchronous mode).
Description Min Typ Max
Jitter 0 7,2
µ
sec
Cycle Time 62,5 64000
µ
sec
Synchronous with DC
In this operating mode data is sampled and then copied into Sync Manager
buffer simultaneously at SYNC0 event generated by the ESC capture/compare
unit.
Time required for accomplishing these operations is set in object 1C33hex; in
particular object “Shift Time” (1C33hex, sub3) and object “Calc & Copy time”
(1C33hex, sub6).
In this operating mode “Jitter” is a fundamental parameter in the sampling of
two consecutive data. The main advantage of this mode is that there is a direct
relation between the sampling instant and the absolute time of the system; in
this way, if we know the shift times of the slaves, we can have an exact image
of the system at a given moment (with a tolerance equal to jitter).
Description Min Typ Max
Jitter 0 100 200
µ
sec
Cycle Time 62,5 64000
µ
sec
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0x1C33:02 (Cycle Time)
0x1C33:05 (Min Cycle Time)
0x1C33:03 (Shift Time) 0x1C33:06
(Calc & Copy)
Jitter
SM3 Event
Input Latch
SM3 Event
Frame N
Frame N+1
0x1C33:02 (Cycle Time)
0x1C33:05 (Min Cycle Time)
Sync0 Event
Frame N
Frame N+1
Sync0 Event
SM3 Event SM3 Event
0x1C33:03 (Shift Time) 0x1C33:06
(Calc & Copy)
Jitter
Input Latch