Cpu Stop Modes - GE PACSystems RXi User Manual

5.5.1

CPU Stop Modes

The CPU has two modes of operation while it is in Stop mode:
■
I/O Scan Enabled - the Input and Output scans are performed each sweep
■
I/O Scan Disabled - the Input and Output scans are skipped
When the CPU is in Stop mode, it does not execute the application program. You can
configure whether the I/O is scanned during Stop mode. Communications with the
programmer and intelligent option modules continue in Stop mode.
In both Stop modes, the Controller Communications and Backplane Communications
windows run in Run-to-Completion mode and the Background window runs in Limited mode
with a 10 millisecond limit.
The number of last scans can be configured in the hardware configuration. Last scans are
completed after the CPU has received an indication that a transition from Run to Stop or Stop
Faulted mode should occur. The default is 0.
The application program can use SVC_REQ13 to stop the CPU after a specified number of
scans. All I/O will go to their configured default states, and a diagnostic message will be
placed in the Controller Fault Table.
GFK-2816F
CPU Sweep in Stop- I/O Disabled and Stop- I/O Enabled Modes
August 2015
Chapter 5. CPU Operation
81