Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual page 433

Error Processing
Intentionally Creating
Errors to Switch Operation
With a Duplex CPU System, a hot standby method is used, which means that
the standby CPU Unit executes the same program as the active CPU Unit.
Thus, if FALS(007) is executed with the same conditions on both the CPU
Units, FALS(007) will be executed at the same time in both CPU Units and
operation will not switch to the standby, causing the CPU STATUS indicators
on the Duplex Unit to flash red for both CPU Units. This is true for other errors
causing operation to switch.
To cause the active CPU Unit to switch during debugging operations, either
use the USE/NO USE switch on the Duplex Unit or use the following type of
programming for FALS(007).
A32808
Duplex/Simplex
Mode Flag
ON: Duplex
OFF: Simplex
Active CPU Unit
Location Flag
ON: Right side
OFF: Left side
Note If the right and left CPU Units are made to perform different operation, they
will not longer be synchronized and a duplex bus error or other error may
occur. Do not use the above type of programming with A32515 (This CPU Unit
Location Flag) for any other application.
A32809 A32515
A32809 A32515
This CPU Unit
Location Flag
ON: Right side
OFF: Left side
Section 10-2
Bit used to switch
operation
FALS
001
#0
397