5.12 Operating modes
5.12.1
Overview
The CPU can be in one of 4 operating modes:
n
Operating mode STOP
n
Operating mode START-UP
n
Operating mode RUN
n
Operating mode HALT
Certain conditions in the operating modes START-UP and RUN
require a specific reaction from the system program. In this case the
application interface is often provided by a call to an organization
block that was included specifically for this event.
n
The application program is not processed.
n
If there has been a processing before, the values of counters,
timers, flags and the process image are retained during the transi-
tion to the STOP mode.
n
Outputs are inhibited, i.e. all digital outputs are disabled.
n
RUN-LED off
n
STOP-LED on
n
During the transition from STOP to RUN a call is issued to the
start-up organization block OB 100. The processing time for this
OB is not monitored. The START-UP OB may issue calls to other
blocks.
n
All digital outputs are disabled during the START-UP, i.e. outputs
are inhibited.
n
RUN-LED
blinks as soon as the OB 100 is operated and for at least 3s, even
if the start-up time is shorter or the CPU gets to STOP due to an
error. This indicates the start-up.
n
STOP-LED off
When the CPU has completed the START-UP OB, it assumes the
operating mode RUN.
n
The application program in OB 1 is processed in a cycle. Under
the control of alarms other program sections can be included in
the cycle.
n
All timers and counters being started by the program are active
and the process image is updated with every cycle.
n
The BASP-signal (outputs inhibited) is deactivated, i.e. all digital
outputs are enabled.
n
RUN-LED on
n
STOP-LED off
The CPU offers up to 3 breakpoints to be defined for program diag-
nosis. Setting and deletion of breakpoints happens in your program-
ming environment. As soon as a breakpoint is reached, you may
process your program step by step.
For the usage of breakpoints, the following preconditions have to be
fulfilled:
Operating mode STOP
Operating mode
START-UP
Operating mode RUN
Operating mode HOLD
Precondition
VIPA System 300S CPU
Deployment CPU 315-2AG13
Operating modes > Overview
HB140 | CPU | 315-2AG13 | GB | Rev. 14-40
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