Lenze PLC Designer PLC Designer (R3-1) - Manual (Page 867)

L-force | PLC Designer
Device Editors

DMS 4.1 EN 03/2011 TD29 865
Implicit variables for forcing I/Os
During the commissioning of a plant or a machine it might be needed to force I/Os, for
example by a HMI visualization. For this purpose special "force variables" can be
generated for each I/O channel which is mapped on a variable in the I/O Mapping
dialog of the device editor.
As a precondition the setting Generate force variables for IO mapping must be
activated in the PLC settings dialog. Then at each build run of the application, for each
mapped IO channel, two variables will be generated according to the following syntax,
whereby any empty spaces in the channel name will be replaced by underscores:
• "devicename“_“channelname“_“IECaddress“_“Force" of type BOOL, for activating
and deactivating the forcing
• "devicename“_“channelname“_“IECaddress“_“Value" of datatype of the channel,
for defining the value to be forced on the channel
These variables will be available in the input assistant in category "Variables",
"IoConfig_Globals_Force_Variables". They can be used in any programming objects, in
visualizations, symbol configuration etc. within the programming system.
A rising edge at the "Force"-Variable activates the forcing of the respective IO with the
value define by the "Value"-Variable. A falling edge deactivates the forcing.
Deactivating by setting the force variable back to FALSE must be done before a new
value can be forced!
Regard the restrictions listed below.
Example
If the mapping is done like shown in figure "Device dialog, I/O Mapping, Example" (see
above), then at a build (F11) of the application the following variables will be
generated and be available in the input assistant:
- Digitax_ST_Control_word_QW0_Force : BOOL;
- Digitax_ST_Control_word_QW0_Value : UINT;
- Digitax_ST_Target_position_QD1_Force : BOOL;
- Digitax_ST_Target_position_QD1_Value : DINT;
- Digitax_ST_Status_word_IW0_Force : BOOL;
- Digitax_ST_Status_word_IW0_Value : UINT;
- Digitax_ST_Position_actual_value_ID1_Force : BOOL;
- Digitax_ST_Position_actual_value ID1_Value : DINT;