Rockwell Automation RECOMM-CNET ControlNet Communications Module - Manual (Page 52)

6-2 ControlNet Communications Module
6.2 Understanding the I/O Image
The terms input and output are defined from the scanner’s point of
view. Therefore, output I/O is data that is output from the scanner
and consumed by the ControlNet module. Input I/O is status data
that is produced by the module and consumed as input by the
scanner.
The I/O image table will vary based on the following:
• Size (either 16-bit or 32-bit) of the Reference/Feedback (Ref/Fdbk
Size (07)) words and Datalink words used by the drive.
• Size (either 16-bit or 32-bit) of the Datalink words (Datalink Size
(08)). If all I/O is not enabled, the image table is truncated. The
image table always uses consecutive words starting at word 0.
Figure 6.1 illustrates an example of an I/O image with 16-bit
words.The configuration is shown to illustrate utilizing 10 words of
inputs and 10 words of outputs. Depending on your application
needs, this may vary.