Rockwell Automation 25-COMM-D PowerFlex 525 DeviceNet Adapter - Manual (Page 43)

Rockwell Automation Publication 520COM-UM002A-EN-E - April 2013 43
Configuring the I/O Chapter 4
b. Enter the number of bytes that are required for your I/O in the Input
Size and Output Size boxes.
For the example in this manual, all four [Opt DL Out 1...4] and all
four [Opt DL In 1...4] are used, resulting in an Input size of “12” and
an Output size of “12”. To determine the byte size for your application,
either view adapter Diagnostic Items 23 (Input Size) and 24 (Output
Size) or calculate them.
View Diagnostic Items 23 and 24 for Input/Output Byte Sizes
Use the PowerFlex 4-Class HIM (22-HIM-A3 or 22-HIM-C2S), or another
drive configuration tool such as Connected Components Workbench to view
Diagnostic Items 23 and 24. The adapter automatically calculates the number of
bytes for the Input Size and Output Size based on the values of
Device parameters
02 [DLs From Net Cfg] and 04 [DLs To Net Cfg] configured in Using Master-
Slave Hierarchy (Optional) on page 26 .
Calculate the Input/Output Byte Sizes
You can easily calculate the number of bytes for the Input size and Output Size.
Since the option module always uses the 16-bit Logic Command, 16-bit
Feedback, 16-bit Logic Status, and 16-bit Reference, at least four bytes must be
set for both the Input Size and Output Size. (A 16-bit word is two bytes).) If any
or all of the drives eight 16-bit Datalinks are used (see
Using Master-Slave
Hierarchy (Optional) on page 26 ), increase the Input and Output Size settings
accordingly.
• Input Size: Multiply the number of Datalinks used to write data (value
of
Device parameter 02 [DLs From Net Cfg]) by two bytes, and add
this result to the minimum four bytes. For example, if
Device parameter
02 has a value of ‘3’, add ‘6’ bytes (3 x 2 bytes) to the required minimum
four bytes for a total of 10 bytes.
• Output Size: Multiply the number of Datalinks used to read data (value
of
Device parameter 04 [DLs To Net Cfg]) by two bytes, and add this
result to the minimum four bytes. For example, if
Device parameter 04
has a value of ‘2’, add ‘4’ bytes (2 x 2 bytes) to the required minimum
four bytes for a total of 8 bytes.
18. Set the scan rate for the selected data exchange method.
For more information about scan rates, see RSNetWorx for DeviceNet
software online help.
19. Click OK.
Data Exchange Method Rate Field Pull-down Setting
Polled Poll Rate
Change of State Heartbeat Rate
Cyclic Send Rate