Rockwell Automation 1756-RIO ControlLogix Remote I/O Communication Interface Module User Manual - Manual (Page 99)

Publication 1756-UM534B-EN-P - November 2010 99
Monitor Remote I/O Chapter 5
Scan Mode and Monitor
Mode The 1756-RIO module can perform various scan functions depending on
whether it is a scanner or an adapter.
Scan Remote I/O in Scanner Mode
There are three scan modes of the ControlLogix controller. The following list
explains each mode and what the 1756-RIO module does in each mode:
• Run mode
• Program mode
• Test mode
In run mode, the 1756-RIO module scans remote racks, reads discrete inputs,
does not enable outputs to run on, and does not update block transfers.
In program mode, the 1756-RIO module scans remote racks, reads discrete
inputs, but does not write discrete outputs, or update block transfers.
In test mode, the 1756-RIO behaves the same as it does in program mode,
with the exception of the controller actively scanning the ladder logic.