tira85e1-a (2014-10) PxG55x.cp 13
4 Object Structure
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 PDOs.
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.
Index (hex.) Object dictionary area
1000 – 1FFF Communication profile area
2000 – 5FFF Manufacturer-specific profile area
6000 – 6FFF Input area
7000 – 7FFF Output area
8000 – 8FFF Configuration area
9000 – 9FFF Information area
A000 – AFFF Diagnosis area
B000 – BFFF Service Transfer area
C000 – EFFF Reserved area
F000 – FFFF
Profile Specific Area
Device area
Explanations for the abbreviations in the columns of the tables are given below:
Abbr. Description
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
CoE CAN application protocol over EtherCAT
Index Object Index (hex.) (address of an object)
NV 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
RxPDO 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.
SI 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)
TxPDO Transmit PDO. A Process Data Object sent from an EtherCAT slave.
4.1 Object Dictionary
structure
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