Rockwell Automation 20-COMM-R Remote I/O Adapter - Manual (Page 37)

20-COMM-R Remote I/O Adapter User Manual
Publication 20COMM-UM004D-EN-P
Chapter 4
Using Discrete and Block Transfer I/O
This chapter provides information and examples about using I/O to control
a connected PowerFlex drive.
About I/O I/O is used to transfer the data which can control the PowerFlex drive and its
speed. It is also used for transmitting data through Datalinks.
The Remote I/O adapter uses Discrete I/O and Block Transfer I/O to
transfer I/O data. The ‘Discrete I/O’ is either 1/4 rack (two 16-bit words) or
1/2 rack (four 16-bit words). The rack size is set using Configuration DIP
Switch SW4 or, if the hardware switches have been disabled, adapter
Parameter 27 - [Rack Size]. The ‘Block Transfer I/O’ includes all Block
Transfer Read or Block Transfer Write messages that are 18 words or fewer.
The type of I/O that is transmitted between the drive and controller is set in
Parameter 12 - [DPI I/O Cfg]. When you set up your I/O, note the
following:
• The Logic Command/Status is always transmitted in the discrete I/O.
• The Reference is transmitted in the Discrete I/O if you are using a 1/2
rack, or in the Block Transfer I/O if you are using a 1/4 rack.
• Datalinks are always transmitted in the Block Transfer I/O.
Topic Page
About I/O 4-1
Understanding the I/O Image 4-2
Discrete I/O Image 4-4
Block Transfer I/O Image 4-7
Example Ladder Logic Program Information 4-11
ControlLogix Controller Example 4-12
PLC-5 Controller Example 4-15
SLC 500 Controller Examples 4-17