WAGO 765-1205/100-000, Product Manual

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765-1205/100-000 Appendix
114 Product manual | Version: 2.0.0
8DIO FLD EC DC 24V 2.0A
14 Appendix
14.1 ISDU Services via AoE
The IO-Link ISDU (Indexed Service Data Unit) service enables reading and writing from
EtherCAT of the parameters of the IO-Link devices connected to the IO-Link master
ports.
The AoE (ADS over EtherCAT) mailbox protocol is used for the connection to EtherCAT.
A mailbox protocol is a protocol whose frames are transferred packaged in the mailbox of
the EtherCAT packet (see
8
AoE – Transfer of ADS Data in the Mailbox of the Ether-
CATFrame [
}
115] ).
The ISDU read and write commands are transferred to and from the IO-Link gateway in
AoE frames via the ADS protocol (ADS = Automation Device Specification).
This approach maps EtherCAT services to IO-Link services and makes the IO-Link ser-
vices available for EtherCAT.
ISDU Read Service
During reading, the user data from the IO-Link device is transferred to the EtherCAT mas-
ter via the ISDU mechanism and the AoE protocol.
ISDU Write Service
During writing, the user data is transferred from the EtherCAT master to the IO-Link de-
vice via the AoE protocol and the ISDU mechanism.
Transferred IO-Link Data
The following IO-Link parameters (ISDU request) are transferred between EtherCAT and
IO-Link via AoE frames:
• The
Port parameter addresses the IO-Link port to which the IO-Link device is con-
nected.
• The Index and Subindex parameters address the object of the IO-Link device. The
documentation of the manufacturer of the IO-Link device used describes the objects
and parameters.
14.1.1 Addressing and Device Identification in AoE
14.1.1.1 Device Identification
An AoE device is identified through two parameters:
• Port Number
• AoE NetId
Port Number
AoE devices are uniquely identified by a fixed port number.