Configuring the Mobile Panel   
6.5 Controlling and evaluating operator controls and display elements 
  Mobile Panels 2nd Generation 
184  Operating Instructions, 09/2018, A5E33876626-AC 
 
Controlling and evaluating operator controls and display elements 
6.5.1
 
The following information can be transferred between the HMI device and the PLC 
depending on the configuration of your HMI device:  
●  Status of the function keys 
●  Status of the keyswitch 
●  State of the illuminated pushbuttons 
●  Status of the LEDs of function keys and illuminated pushbuttons 
 
Note 
The status of the function keys and corresponding LEDs is communicated as soon as a 
corresponding project has started on the HMI device.
 
The status of the keyswitch, illuminated pushbuttons and corresponding LEDs is 
communicated as s
oon as the HMI device is connected to a connection box. 
The options for transmitting information are as follows: 
●  Direct keys 
These are described in "Evaluating operator controls as direct keys (Page 184)". 
●  System functions of WinCC 
These are described in  
"Controlling the LEDs of the function keys by means of system functions (Page 187)". 
 
Evaluating operator controls as direct keys 
You can configure the operator controls of the HMI device as direct keys. The states of the 
following operator controls are available directly in the I/O area of the PLC: 
●  The switching state of the function keys 
●  The switching state of the keyswitch 
●  The switching state of the illuminated pushbuttons 
The tables below show the assignment of the key inputs and LED outputs to the bytes in the 
PLC process image. Refer to your plant documentation for additional information.