Creating a New Data Item in SNMP Connector

You can add a new item or, specifically a new SNMP Tag, to a device in the Project Explorer on the SNMP Connector in the GENESIS64 Workbench.

To Add a New Item (SNMP Tag):

  1. Right-click on a device, then click Tag.

Adding a Tag

-OR-

Select a device in the Project Explorer, then click the ClosedAdd button in the Edit section of the Home ribbon, then click on Tag.

Adding a Tag

  1. Creating a new tag or clicking on an existing tag causes the following screen to appear.

Item (Tag) Properties in SNMPConnector in GENESIS64 Workbench

From here you can configure all the information about the SNMP tag:

  • Name: Enter the name of the SNMP Tag. The name of the tag is critical. For Scalar Values, Table Tags and Array Tags (see Exploring the Network), you can change the name of the tags, without limits. For array elements, it is dangerous to change the ending part of the name because it contains information about the Full OID itself.

Snmp Data

  • Full OID: The identifier for every SNMP tag is the Full OID. This information enables the retrieval of the associated data in the MIB dictionary tree (if it exists).

  • Syntax: Specifies the SNMP type of the tag. It can also be a table, but only if the SNMP item associated with the tag (which has the very same Full OID) is a table, too.

  • Override Update Rate: Check the Override Update Rate check box and then you can enter a device Update Rate only for the selected tag.

  • Use GetNext: Check this check box to retrieve values through a Get-next instead of the default Get. This field is disabled for Array Data, Table Data, and writable tags.

  • Data Type: Specifies the OLE data type, and is identical to the OPC data type. This field must be set to Array for SNMP tables.

  • Access: A tag can be readable, writable, both or none.

  • Update Rate:

MIB Data

The MIB Data section is automatically entered when the Snmp Data section is completed and the SNMP Tag is saved.

  • Name

  • Syntax

  • Access

  • Description

Example Tag Configuration in SNMP Configurator

In the example above, the name of the tag is composed by the SNMP Item name and the index of the Array (which is the IP Address 10.1.2.17). To retrieve in runtime the value of the tag, the Full OID "1.3.6.1.2.1.4.20.1.1" (which is the same Full OID of the SNMP Object ipAdEntAddr ) and the index of the Array "10.1.2.17"  are concatenated so that the real "address" of the information can be obtained: "1.3.6.1.2.1.4.20.1.1.10.1.2.17". If the index is changed or deleted, the data will not be retrievable anymore. However you can change the index coherently to obtain different elements of the array.

See also:

Data Items

SNMP Connector