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02/2020 | ID 443025.06
Changing the cycle sequence
For cycle times < 1ms, change the cycle sequence of the application to RxPDO, TxPDO, graphical programming (A149 = 1). The following example shows a synchronization with a changed
cycle sequence. The frame jitter (controller) and application jitter (drive controller) are separated and synchronization is stable.
Beckhoff CX2030
Frame
SYNC Shift Time
Shift Time User Defined
Data ready
SYNC 0
PLL phase offset
AR1
Cycle time Cycle time
NC+PLC NC+PLC NC+PLC
APPAPP
= Jitter
Cycle time
Fig.19: TwinCAT 3: DC-Sync – Stable synchronization, cycle time < 1ms