Rockwell Automation 20-COMM-D DeviceNet Adapter Series B FRN 2.xxx - Manual (Page 162)

6-34 Using Explicit Messaging
20-COMM-D DeviceNet Adapter User Manual
Publication 20COMM-UM002G-EN-P
SLC 500 Controller – Formatting a DEM Instruction Message to Write a Single
Parameter
Figure 6.39 Generic Set Attribute Single DEM Message Configuration Screen
The following table identifies the data that is required in each box to
configure a message to write 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 (2)
1
2
5
1 (Dec.)
Generic Set Attribute Single
93 (Hex.)
140 (Dec.)
9 or 10 (Dec.)
The chassis slot occupied by the scanner.
Number of bytes to be sent (written). Two bytes equal a 16-bit integer (word).
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).
(2) Setting the Attribute value to ‘9’ will write the parameter value to the drive’s Nonvolatile Storage (EEPROM) memory, which retains the parameter value even
after the drive is power cycled. Important: When set to ‘9’, the EEPROM may quickly exceed its life cycle and cause the drive to malfunction. Setting the
Attribute value to ‘A’ (10 decimal) will write the parameter value to temporary memory, which deletes the parameter value after the drive is power cycled.
When frequent write messages are required, we recommend using the ‘A’ (10 decimal) setting.