MP 277 - Service, Support Download

Operating a project
8.2 Direct keys
Acoustic feedback from operating elements
An acoustic signal is generated as soon as the HMI device detects that the touch screen has
been touched or a key has been pressed. You can activate or deactivate this acoustic
operation feedback.
The acoustic feedback is only possible if you interact with the project directly on the touch
screen or press one of the keys of the HMI device. If you use an external mouse or keyboard
for interaction, no acoustic signal is issued.
Acoustic signal for inadvertent operations
If you try to enter an invalid character, the HMI device issues an acoustic signal in
accordance with the setting.
See also
Set the volume (Page 97)
Direct keys
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
Direct keys are still active when the HMI device is in "offline" mode.
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.
You can only use direct keys when there is a connection via PROFIBUS DP or
Direct keys result in additional basic load on the HMI device.
MP 277
Operating Instructions, 07/2014, A5E02479740-02