How do you implement the "Clean Screen" function for cleaning the touch screen on Mobile Panels and OP 177B?
With Windows-based touch panels you have the option of using the "Clean Screen" function to disable the touch surface in order to clean it. Mobile Panel 17x, Mobile Panel 277 and OP 177B do not support this standard function (see Entry ID: 14557829).
The sample program that is available in this entry for downloading contains two versions for simulating the Clean Screen function for these panels.
Please note the following restrictions when implementing the sample program:
- The simulated Clean Screen only disables the touch surface of the panel. All other controls on the device remain active during the cleaning phase.
- The permanent window (see also: Notes on the permanent window) can not be disabled with this function if you have configured the permanent window.
Implementing the "Clean Screen" function on OP 177B without PLC job
|2||In "Cleanscreen", the global assignment of key "F2" is overwritten by a local assignment with "ActivatePreviousScreen".|
Implementing the "Clean Screen" function on OP 177B with PLC job
|2||Insert the "Job Mailbox" and "Screen Number" area pointers in your WinCC flexible project in order to implement the "Clean Screen" function. The job mailbox is needed to be able execute control jobs like "Screen Selection" on the OP 177B. The "Screen Number" user-data area displays information about the screen just selected on the OP 177B (e.g. current screen number, field number). This information is required to display the previous screen on the panel after the cleaning phase with the "Clean Screen".
|3||Description of the STEP 7 program|
The STEP 7 program consists of OB1, FB100 and its instance data block DB100.
The example includes a STEP 7 V5.4 project with a CPU 316-2DP and two OP 177Bs. It was created with STEP 7 V5.4 SP1 HF2 and WinCC flexible 2005 SP1 HF7. The example has the functionality described above.
OP177B_Cleanscreen.zip ( 4542 KB )
Open and copy the "OP177B_Cleanscreen.zip" file into a separate directory. Unpack the STEP 7 project with integrated WinCC flexible project with all the associated subdirectories. You can then use the SIMATIC Manager and WinCC flexible to open and process the extracted project.
Notes on the permanent window:
If you use a permanent window in which there are active elements (e.g. input fields, button), you can still use the clean screen. For this you must define a Boolean tag which needs no controller connection. Then this tag is assigned to the active objects in the permanent window under "Visible" and hidden with Value 1. In the clean screen, for this tag only the SetBit function has to be assigned in the "Set up" event, and the ResetBit function for the "Cleared down" event. This ensures that these objects are not operated inadvertently during cleaning.
MP170, MP177, MP277, OP177, Clean, Inoperable touch, Touch screen