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easiest way to execute the Set Attribute Single service on a remote device 
is to use the NI-DNET 

ncSetDnetAttribute

 function.

For a given attribute of a DeviceNet device, you need the following 
information to use the 

ncGetDnetAttribute

 or 

ncSetDnetAttribute

 

function:

•

The class and instance identifiers for the object in which the attribute 
is located

•

The attribute identifier

•

The attribute’s DeviceNet data type

You can normally find this information from the object specifications 
contained in the DeviceNet Specification, but many DeviceNet device 
vendors also provide this information in the device’s documentation.

For the C programming language, the attribute’s DeviceNet data type 
determines the corresponding NI-DNET data type you use to declare a 
variable for the attribute’s value. For example, if the attribute’s DeviceNet 
data type is 

INT

 (16-bit signed integer), you should declare a C language 

variable of type 

NCTYPE_INT16

, then pass the address of that variable as 

the 

Attr

 parameter of the 

ncGetDnetAttribute

 or 

ncSetDnetAttribute

 function.

For LabVIEW, the attribute’s DeviceNet data type determines 
the corresponding LabVIEW data type to use with the 

ncConvertForDnetWrite

 or 

ncConvertFromDnetRead

 functions. The 

ncConvertFromDnetRead

 function converts a DeviceNet attribute read 

using 

ncGetDnetAttribute

 into an appropriate LabVIEW data type. The 

ncConvertForDnetWrite

 function converts a LabVIEW data type into an 

appropriate DeviceNet attribute to write using 

ncSetDnetAttribute

. For 

more information on these LabVIEW conversion functions, refer to the 

 section.

To execute services other than Get Attribute Single and Set Attribute Single, 
use the following sequence of function calls: 

ncWriteDnetExplMsg

, 

ncWaitForState

, 

ncReadDnetExplMsg

. The

ncWriteDnetExplMsg

 

function sends an explicit message request to a remote DeviceNet device. 
The 

ncWaitForState

 function waits for the explicit message response, 

and the 

ncReadDnetExplMsg

 function reads that response.

Use 

ncWriteDnetExplMsg

 for such DeviceNet services as Reset, Save, 

Restore, Get Attributes All, and Set Attributes All. Although the DeviceNet