Chapter 3 Programming
3 – 15
3.4 I/O-update
Input data is read at the beginning of a task and output data is written at the end of a task. I/O-update settings are
configured in “PLC settings” in Device tab. Be noted that only used I/Os in program are updated.
Update IO while in stop
If this option is activated (default), the values of the input and output channels get also updated when the PLC is
stopped.
Behaviour for outputs in Stop
Keep current values: The current values will not be modified. If “Update IO while is stop” is deactivated,
output data is not updated at CPU stopping.
Set all outputs to default: The default values resulting from the mapping will be assigned. If this setting is
used, “Reset all outputs in STOP” of [Device]-[Configurtion] parameter must be set as “No”, otherwise default
value of TRUE is not valid. Refer to the next page for further information.
Execute program: You might determine the outputs behaviour by a program available within the project. Enter
the name of this program here and it will be executed when the PLC gets stopped. Via button [...] the input
Assistant can be used for this purpose.
Update all variables in all devices
If this option is activated, then for all devices of the current PLC configuration all I/O variables will get updated
in each cycle of the bus cycle task. This corresponds to option “Always update variables”, which can be set
separately for each device in the "I/O Mapping" dialog.
If all the following conditions are fulfilled and reset warm/cold is operated, the last status of output module remains
although monitored output status is reset.
- Update IO while in stop in PLC settings: Disabled
- Behavior for outputs in Stop in PLC settings: Keep current values
This is expected behaviour. If this setting combination is required, keep in mind this mismatching and
be careful to use.
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