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