Function Keys - Siemens SIMATIC TP 270 Operating Instructions Manual

5.2.2

Function keys

Function keys with global function assignment
A softkey with global function assignment always triggers the same action on the HMI device
or in the PLC. The action is independent of the screen currently selected. These actions
include:
• Activate screen
• Display current error alarms
• Start screen printout (hardcopy)
All softkeys can be configured with global assignments.
Note
Multiple key operation can trigger unintentional actions.
No more than two softkeys may be pressed simultaneously.
Softkeys with local function assignment
A softkey with local function assignment can trigger different actions on the HMI device or in
the PLC. The actions are dependent on the currently active screen (local significance of
current screen). A configuration engineer can configure an icon for each softkey. The icon is
then positioned at the edge of the screen.
The F-keys can be locally assigned.
Caution
If you press a function key after a screen change, the associated function in the new screen
may be initiated before the new screen is displayed.
LED control
The light-emitting diodes (LED) in the function keys can be controlled from the PLC. A
luminous or flashing LED can indicate to the operator which key to press according to
specific situations.
To trigger the LEDs, the configuration engineer must configure LED tags for the softkeys.
TP 270, OP 270, MP 270B (WinCC flexible)
Operating Instructions, Edition 03/2004, 6AV6691-1DD01-0AB0
Operating elements and indicators
5.2 MP 270B Keys and OP 270
5-5