Topic
All data is tagged with a topic string. The topic is a unique identifier used to route publications to its subscribers when they are published by a certain device to the broker.
The topic is either set by the host application, by responding to the Get_Publish_Configuration command that is sent to the MQTT Host Object (E2h), or generated by the Anybus CompactCom with help of metadata of the ADIs that are being published.
The generated topic string has the following format:
<base topic>/<dataset type>/<dataset identifier>
Each entry of the generated topic format can consist of several levels separated by “/” characters. The base topic level is retrieved from the Network Configuration Object (04h), instance #55. The other topic levels are specific to each dataset, according to the table below.
Dataset | Dataset Type | Dataset Identifier |
|---|---|---|
Single ADI | “Parameter” | ADI name as given by attribute #1 of the ADI instance in the Application Data Object (FEh). If this attribute is not implemented, the default value will be used. Max 32 characters Default value: “Param<ADI number>” |
Assembly mapping instance | “Assembly” | Assembly mapping instance name as given by attribute #13 of the assembly mapping instance in the Assembly Mapping Object (EBh). If this attribute is not implemented, the default value will be used. Max 32 characters Default value: “Asm<assembly mapping instance number>” |
Transparent network payload | “Transparent” | The dataset identifier in decimal format without leading zeroes. Vendor specific. |