Oriental motor aSTEP AZ mini Driver, Руководство пользователя

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Communications specifications
40
3 E
therC
AT c
ommunica
tion
2-3 EtherCAT state machine (ESM)
The EtherCAT state machine (ESM) is controlled by the EtherCAT master.
Init
Pre-Operational
Safe-Operational
Operational
ESM State
SDO
communication
Transmit PDO
(TxPDO)
Receive PDO
(RxPDO)
Status
Init Not possible Not possible Not possible
During initialization. Communication
cannot be performed.
Pre-Operational Possible Not possible Not possible
The mailbox communication (SDO) can be
performed. The process data
communication (PDO) cannot be
performed.
Safe-Operational Possible Possible Not possible
The mailbox communication and the
transmit PDO can be performed. The status
of the driver can be sent to the EtherCAT
master by the transmit PDO.
Operational Possible Possible Possible
The mailbox communication, transmit
PDO, and receive PDO can be performed.
Commands can be sent from the EtherCAT
master to the driver by PDO
communication.
2-4 Process data object (PDO)
Process data object (PDO) is used in real-time data communication of EtherCAT communication.
There are two types of PDO: transmit PDO (TxPDO) and receive PDO (RxPDO). The transmit PDO (TxPDO) is to send
data from the driver to the EtherCAT master. The receive PDO (RxPDO) is to receive data from the EtherCAT master to
the driver.
Contents, which are sent and received using PDO, are set by the PDO mapping object and the Sync manager 2 and
Sync manager 3 PDO assignment objects.
The PDO mapping is to set the PDO mapping object.
Sync manager 2 PDO assignment and Sync manager 3 PDO assignment are to set the PDO mapping object that
performs communication actually.
The PDO mapping object is consisted of 4 bytes that are indexes of assigned object (Index), sub-index (Sub-index),
and data length (Length). Only data of 08h (1 byte), 10h (2 bytes), and 20h (4 bytes) can be set in the data length.
Index Sub-index Data length
(2 bytes) (1 byte) (1 byte)