FM 456-2 Functions and Technical Data
4-4
FM 456-2 Application Function Module Installation, Hardware, and Startup
C79000-G7076-C458-01
4.3
Mode Selector
Mode Selector
The mode selector on the FM 456-2 is in the form of a key switch.
The following illustration shows the location and positions of the mode selector.
MRES
STOP
RUN
RUN-P
Figure 4-2
FM 456-2 Mode Selector
The settings of the mode selector can be examined by the software. The
significance of the individual switch positions can thus vary depending on the
program.
Mode Selector Positions
Table 4-3
FM 456-2 Mode Selector Positions
Mode Selector
Position
Explanation
RUN-P
The FM 456-2 processes the user program. Write and read access
to the CPU are possible.
The key cannot be removed when in this position.
RUN
The FM 456-2 processes the user program. Read access only to
the CPU is possible.
The key can be removed in this position to prevent unauthorized
change of mode.