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•

Execute the DeviceNet Set Attribute Single service on the remote 
device (

ncSetDnetAttribute

)

•

Send any other explicit message request to the remote device and 
receive the associated explicit message response 
(

ncWriteDnetExplMsg

, 

ncReadDnetExplMsg

)

•

Configure NI-DNET settings that apply to the entire remote device

The I/O Object represents an I/O connection to a remote DeviceNet device 
(physical device attached to your interface by a DeviceNet cable). The 
I/O Object usually represents I/O communication as a master with a remote 
slave device, but it can also be used for I/O communication as a slave.

The I/O Object supports as many master/slave I/O connections as currently 
allowed by the DeviceNet Specification. This means that you can use 
polled, strobed, and COS/cyclic I/O connections simultaneously for a given 
device. As specified by the DeviceNet Specification, only one master/slave 
I/O connection of a given type can be used for each device (MAC ID). For 
example, you cannot open two polled I/O connections for the same device.

Use the I/O Object to do the following:

•

Read data from the most recent message received on the 
I/O connection (

ncReadDnetIO

)

•

Write data for the next message produced on the I/O connection 
(

ncWriteDnetIO

)

Figure 1-2 shows an example of how NI-DNET objects can be used to 
communicate on a DeviceNet network. This example shows three 
DeviceNet devices. The first device (at MAC ID 1) is the National 
Instruments DeviceNet interface. The second device (at MAC ID 5) uses 
NI-DNET to access a polled and a COS I/O connection simultaneously. 
The third device (at MAC ID 8) uses NI-DNET to access an explicit 
messaging connection and a strobed I/O connection.