Operating instructions

Operating a project
6.2 Function keys
Comfort Panels
156 Operating Instructions, 03/2012, A5E03404994-02
6.2 Function keys
Function keys
Function key assignment is defined during configuration. The configuration engineer can
assign function keys globally and locally.
Function keys are available only on key HMI devices.
Function keys with global function assignment
A globally assigned function key always triggers the same action on the HMI device or in the
PLC irrespective of the screen displayed. Such an action could be, for example, the
activation of a screen or the closure of an alarm window.
Function keys with local function assignment
A function key with local function assignment is screen-specific and is therefore only
effective within the active screen.
The function assigned locally to a function key can vary from screen to screen.
The function key of a screen can be assigned one function only, either a global or local one.
The local assignment function takes priority over the global setting.
The configuration engineer can assign function keys in such a way that you can manipulate
operating elements with function keys, for example, the alarm view, trend view, recipe view
or status/force.
6.3 Direct keys
Introduction
Direct keys on the HMI device are used to set bits in the I/O area of a SIMATIC S7.
Direct keys enable operations with short reaction times that are, for example, a jog mode
requirement.
NOTICE
Direct keys are still active when the HMI device is in "offline" mode.
NOTICE
If you operate a function key with direct key functionality in a running project, the direct key
function is always executed, independent of the current screen contents.
Note
You can only use direct keys when there is a connection via PROFIBUS DP or
PROFINET IO.
Direct keys result in additional basic load on the HMI device.