Festo CMMT-ST-SW, Оригинальное руководство пользователя

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1
st
Slave
Clock Master
2
nd
Slave
Clock Slave
Master
Clock Slave
3
rd
Slave ... Slave
Clock Slave
Ref Time Ref Time
1)
Ref Time Ref Time
Ref Time
Ref Time
Ref Clock
Ref Time
DC Time DC Time DC Time DC Time
Offset Offset Offset Offset
Fig. 109 DC-topology and synchronisation of the EtherCAT network
11.7 Process data communication
With process data communication (Process data communication), process data (e.g. setpoint and
actual values) are exchanged cyclically between the CMMT and the network devices (e.g. controller
(Controller)). With every process data frame that is run through the output process data (Process data
output) are read from the frame and the input process data (Process data input) are written to the
frame. In the CMMT the controller for process data communication is assigned permanently to Sync
Managers 2 and 3 for transmission of mapped process data objects (PDO) (Process data objects). Max.
16 output/input objects (Sub: 0x01 … …0x10) with 64 bytes user data each can be assigned to the
process data objects (RxPDO/TxPDO).
Process data communication is active from the "Safe Operational" status. The CMMT transmits the
current actual values (TxPDO) to the controller from this status. After the "Operational" status is
reached, incoming setpoint values (RxPDO) are processed and executed by the CMMT.
Synchronisation of the CMMT can be controlled by the Distributed Clocks DC
è 11.6 Distributed clocks DC (Distributed Clocks).
Controller
RxPDO
TxPDO
CMMT
Process data output
Process data input
RxPDO Mapping
Object 0x1600
TxPDO Mapping
Object 0x1A00
cyclical
CoE
Object directory
Fig. 110 Access procedure via process data objects PDO
EtherCAT
531 Festo — CMMT-ST-SW — 2019-02