ABB RECA-01, User Manual

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Communication
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Format of the PDO mapping (example for drive parameter 12.02)
Note: The maximum number of I/O parameters that can be
simultaneously mapped for cyclic communication depends on the
drive type and application. For example, ACS800 supports 12
inputs and 12 outputs and ACS550 supports 15 outputs and 15
inputs.
Service Data Objects (SDOs)
Service Data Objects are mainly used for transferring non time-
critical data, e.g. parameter values. EtherCAT® specifies both
SDO services and SDO Information services: SDO services
provide read/write access to the entries in the device CoE Object
Dictionary. SDO Information services allow the Object Dictionary
itself to be read. The services supported by RECA-01 are
described in table
Supported SDO and SDO Information services
below.
Supported SDO and SDO Information services
Type MSB LSB
UNIT 32 31 16 15 8 7 0
Description Index
e.g 0×400C (hex)
Drive parameter
group 12 (16 bits)
Sub index
e.g 2 Drive
parameter group 12
(8 bits) Object length in bits
e.g 0×10 (hex) =
16 bits
(8 bits)
Service Function
SDO Download Expedited Writes up to four octets to the slave.
SDO Download Normal Writes up to a negotiated number of octets to the
slave.
Download SDO Segment Writes additional data if the object size is greater than
the negotiated number of octets.
SDO Upload Expedited Reads up to four octets from the slave.
SDO Upload Normal Reads up to a negotiated number of octets from the
slave.
Upload SDO Segment Reads additional data if the object size is greater than
the negotiated number of octets.
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