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10. Appendix D: DeviceNet Objects
Attributes of instances 16#01 to 16#04 of class 16#05
Service code Name of the service Need Description
16#0E Get_Attribute_Single Required This service allows to read the va lue of one of the attributes from
one of the instances of the “Connection Object.”
16#10 Set_Attribute_Single Optional This service allows to write the value of one of the attributes from
one of the instances of the “Connection Object.”
10.9. Acknowledge Handler Object (class 16#2B)The “Acknowledge Handler” object has only one instance (Instance ID = 16#01). This object is used by
connections whose producer needs to know whether its data has been received by its recipient(s) (consumers).
This object is described in chapter 6-31. of volume II of the DeviceNet specifications.
Attributes of class 16#2B
ID Access Name Need Type Value Description
16#01 Get Revision Optional UINT 1 Revision index of the “Acknowledge Handler Object”
class.
16#02 Get Max
instance
Optional UINT 1 Maximum number of any instance created within the
“Acknowledge Handler Object” class.
Services in class 16#2B
Service code Name of the service Need Description
16#0E Get_Attribute_Single Required This service allows to read the value of one of the attributes of the
class.
Attributes of instance 16#01 of class 16#2B
ID Access Name Need Type Value
16#01 Get / Set Acknowledge timer Required UINT 20 (unit: 1ms)
The value of this attribute determines the waiting time for acknowledgement of the message from a connection.
Once this time has elapsed, the gateway proceeds to re-transmit the message which has just failed to be
acknowledged. The value of this attribute ranges from 1 to 65,535, and its default va lue is 20.
16#02 Get / Set Retry limit Required USINT 1
This attribute determines the maximum number of times that the acknowledge timeout can be successively
triggered for the same message, and therefore the number of re-transmissions allowed for each message. The
value of this attribute ranges from 0 to 255, and its default value is 1.
16#03 Get / Set COS producing connection instance Required UINT 4
The value of this attribute is set to the instance number (Instance ID) of the “Connection Object” class
corresponding to the “Change-of-State” connection associated with the “Acknowledge Handler” object. This
association allows the latter to transmit the acknowledgements it receives to the corresponding connection if they
are addressed to it.
16#04 Get Ack list size Optional BYTE 1
This attribute represents the maximum number of members which can be placed in the ack list. If the value of this
attribute is null, the size of the list is dynamic, which is not the case with the LUFP9 gateway.
16#05 Get Ack list Optional BYTE , USINT […] 0 , (empty list)
This attribute corresponds to the list of active instances of the “Connection Object” class for which the receipt of
an acknowledgement is required. It is made up of two elements: The number of members (BYTE) and the list of
the associated instance numbers from the “Connection Object” class (USINT […]). The size of the list is set to the
value of the first element. By default, the list is empty (no term of the USINT type […]) and only the BYTE
element is created.
E.g. “1, 4“ for a list comprising a single instance of the “Connection Object” class. This instance (16#04)
corresponds to the “Change-of-State / Cyclic (Acknowledged) Connection”).