Rockwell Automation 5370-CVIM2 Module - Manual (Page 466)

5 Chapter Chapter 9
Discrete I/O Assignments
9–3
•
Cancel –– Use the button to exit to the main menu bar without
saving any of the additions or changes in the I/O panel.
•
Module I/O –– Use the button to select the I/O Device panel,
from which you can select the other I/O panels: the System I/O panel,
the LED Outputs panel, and the Remote I/O panel. The current selection
appears in this button.
•
Goto –– Use the button to access the second half (rows 8 through
15) of the Module I/O or System I/O panels when you are using an
Allen–Bradley Catalog No. 2801–N8 color monitor, or equivalent
RS–170 monitor in the panel.
When you are using a VGA monitor, the button is active only when the
Remote I/O panel is selected. In this case, the button selects the
keyboard, which you can use to access a specific remote I/O address.
Note that the Discrete I/O Editor panel appears in four formats, according to
the selection that you make in the I/O Device panel: Module I/O , System
I/O , LED Outputs and Remote I/O . The differences between these four
panels are described in the remaining sections of this chapter.
Relation of Discrete I/O Assignments to Configuration File
Discrete I/O assignments are described in files whose file type name is
“
Discrete I/O ” in the EE or other filer. The Discrete I/O files are created
(named) in the Config Files panel, using the same methods that are used to
create the configuration, message, and acquisition configuration files, and
described in Chapter 4, Inspection Configuration under the Configuration
Process heading on page 4–2.
Multiple files can be named under the “ Discrete I/O ” file type name;
however, only one can be selected for a particular configuration file and
“saved” as part of that file. The effect is that when an existing configuration
file name is selected, the associated discrete I/O file is automatically
accessed.
Discrete Inputs: Interrupt Processing vs Poll Processing
The CVIM2 system uses two methods to process input signals: interrupt,
and polling. The main difference is that the interrupt method is faster than
the polling method; thus, this method is preferable for inputs that generally
require immediate response, such as triggers. The polling method is adequate
for inputs that are less time–critical, such as bank switching.