tirb45e1 (2019-02) CDGxxxDxx.cp 37
5 Object Structure CDG045Dhs, CDG100Dhs, CDG160Dhs, CDG200Dhs
This chapter describes the CANopen over EtherCAT (CoE) Object Dictionary.
The objects in the CoE Object Dictionary can be accessed with SDO services, and
many of the dictionary objects can be mapped for cyclic communication in PDO's.
Each object is addressed using a 16-bit index and an 8-bit subindex.
The following table presents the overall layout of the standard Object Dictionary.
Communication profile area
Manufacturer-specific profile area
Profile Specific Area
Explanations for the abbreviations in the columns of the tables are given below:
Access SDO read/write access
• RO: object can only be read by the SDO service
•
RW: object can be both read and written by the SDO service
CAN application protocol over EtherCAT
Object Index (hex.) (address of an object)
Nonvolatile; attribute value is maintained through power cycles
Object Abstract representation of a particular component within a device,
which consists of data, parameters, and methods.
PDO Process Data Object. Structure described by mapping parameters
containing one or several process data entities.
PM PDO mapping
• Rx: object can be mapped into an Rx PDO
•
Tx : object can be mapped into a Tx PDO
Receive PDO. A Process Data Object received by an EtherCAT slave.
SDO Service Data Objects. CoE asynchronous mailbox communications
where all objects in the Object Dictionary can be read and written.
Subindex (hex.) (sub-address of an object)
Type Data Type
• BOOL, BIT = 1 bit. Boolean (0 = false, 1 = true)
• USINT, BYTE = 8 bit. Unsigned Byte
• UINT = 16 bit. Unsigned integer value
• UDINT = 32 bit. Unsigned integer value
• ULINT = 64 bit. Unsigned integer value
• REAL = 32 bit. Floating point
•
V_STRING = 8×n bit. Visible string (1 byte for character)
Transmit PDO. A Process Data Object sent from an EtherCAT slave.
5.1 Object Dictionary