User manual

Configuration 3-17

DeviceNet I/O Configuration

I/O Mapping

The DeviceNet I/O configuration defines the format of the Input and Output tables

in the PassageWay, or the mapping of DeviceNet slaves’ I/O data to the I/O

tables. See “Theory of Operation” on page 1-2 for a discussion on the Passage-

Way and the use of I/O tables in the BridgeWay. As slaves are added to the

BridgeWay’s DeviceNet scanner configuration, the location in the I/O tables of

each part of the slave’s I/O data is determined and stored.

Note: The organization of the I/O tables is very important. This defines the format

of the data that will be exposed to the EtherNet/IP or Modbus/TCP scanner. The

Input and Output table formats should be planned and documented to ensure the

Ethernet scanner is working with the correct data from the DeviceNet network.

I/O Size Limitations

The size of the I/O data that can be exchanged with the EtherNet/IP or Modbus/

TCP scanner and, hence, the size of the I/O tables is restricted as explained below.

• The Input table (data coming from DeviceNet devices) size cannot be

larger than 496 bytes.

• The Output table (data being sent to DeviceNet devices) size cannot be

larger than 492 bytes.

• Either table may be empty (size of 0 bytes).

DeviceNet Configuration Tools

The DeviceNet I/O configuration is set using a DeviceNet configuration tool. This

manual is not intended to replace the user manual for the configuration tool; hence

it will not provide details on using the tool.

The next chapter provides an example application, and provides an overview of

the use of Rockwell Software’s RSNetWorx for DeviceNet and HMS’ NetTool-

DN-D.