Rockwell Automation 20-COMM-D DeviceNet Adapter Series B FRN 2.xxx - Manual (Page 160)

6-32 Using Explicit Messaging
20-COMM-D DeviceNet Adapter User Manual
Publication 20COMM-UM002G-EN-P
SLC 500 Controller Explicit Messaging Using the Generic Get/Set
Attribute Service
SLC 500 Controller Example DEM Instruction Ladder Logic Program to Read a
Single Parameter
A Generic Get Attribute Single message is used to read a single parameter.
This read message example reads the value of parameter 003 - [Output
Current] in a PowerFlex 7-Class drive.
Figure 6.35 Example Ladder Logic to Read a Single Parameter
SLC 500 Controller – Formatting a DEM Instruction Message to Read a Single
Parameter
Figure 6.36 Generic Get Attribute Single DEM Message Configuration Screen
The following table identifies the data that is required in each box to
configure a message to read a single parameter.
General Tab Example Value Description
1747-SDN Slot
Size of Send Data (Bytes)
Message Timeout
DeviceNet Addr
Service (1)
Class
Instance
Attribute
1
0
5
1 (Dec.)
Generic Get Attribute Single
93 (Hex.)
3 (Dec.)
9 (Dec.)
The chassis slot occupied by the scanner.
Number of bytes to be sent. For a read message, always set to zero (0).
The time (in seconds) that the message must be completed.
The node address of the adapter connected to the drive.
Code for the requested service.
Class ID for the DPI Parameter Object.
Instance number is the same as the parameter number.
Attribute number for the Parameter Value attribute.
(1) The default setting for Service is ‘Custom’, enabling entry of a Service Code not available from the Service pull-down menu. When choosing a Service
other than ‘Custom’ from the pull-down menu, an appropriate Hex. value is automatically assigned to the Service Code box which is dimmed
(unavailable).