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Entry type: FAQ, Entry ID: 18748365, Entry date: 07/11/2007

How do you implement the "Clean Screen" function for cleaning the touch screen on Mobile Panel 170?

  • Entry
  • Associated product(s)

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 170 does not support this standard function (see Entry ID: 14557829).

The sample program that is available in this entry for downloading contains a simulated Clean Screen function for the Mobile Panel 170.

Please note the following restrictions when implementing the sample program:

  • The simulated Clean Screen only disables the touch surface of the Mobile Panel 170. All other controls on the device remain active during the cleaning phase.
  • The permanent window can not be disabled with this function if you have configured the permanent window.

Implementing the "Clean Screen" function on Mobile Panel 170

No. Procedure
1 Configuration steps required in ProTool
  • In your ProTool project you add a screen entitled "Clean Screen".
  • The "Clean Screen" screen has no controls, only the lettering "Clean Screen".

Fig. 01

2 Tag declaration in ProTool
  • Add a Boolean tag (in a marker area or DB in the controller) to your project.
  • Configure the "Set_bit" function with this tag as parameter on a global key in order to trigger a program with it in the controller. The program in the controller enables selection of the clean screen on the panel.

Fig. 02

3 Set up the area pointer required in ProTool
  • Insert the "Job Mailbox" and "Screen Number" area pointers in your ProTool project in order to implement the "Clean Screen" function. The job mailbox is needed to be able execute control jobs like "Picture Selection" on the Mobile Panel 170. The "Screen Number" user-data area displays information about the screen just selected on the Mobile Panel 170 (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".

Fig. 03

More information on the "Screen Number" and "Job Mailbox" area pointers are available in the communication manual for Windows-based systems in Entry ID: 1405528.

4 Description of the STEP 7 program

The STEP 7 program consists of OB1, FB100 and its instance data block DB100.

  • FB100

If the Boolean tag created in ProTool is set, the current screen number and field number from the "Screen Number" interface area (ProTool area pointer) are stored in static tags. Then the parameters of the "Picture Selection" job (job number 51) are written to the job mailbox. Please note that as screen number for the job you must specify the screen number of the "Clean Screen" screen. As final parameter you enter the job number 51 in the area of the job mailbox provided so that the control job can be executed. The "Clean Screen" screen is displayed on the panel. You can set the display time of the "Clean Screen" screen with a timer. Once the timer time expires, the "Picture Selection" job is executed again with the static tags as parameters in order to activate the original screen.

  • DB100

In DB100 are the "Job Mailbox" and "Screen Number" area pointers, the static tags for storing the screen and field numbers and the Boolean tag for activating the "Clean Screen" screen.

  • OB1 

In OB1 a check is made whether the job mailbox is free (job number = 0) and then FB100 with instance DB is called.

The STEP 7 and ProTool project as download
The example contains a STEP 7 V5.2 project with a CPU 316-2DP and a MOBILE PANEL 170. It was created with STEP 7 V5.2 SP1 and ProTool/Pro CS V6.0 SP2. The example has the functionality described above.

MobilePanel170_clean.zip ( 310 KB )

Open and copy the "MobilePanel170_clean.zip" file into a separate directory. Unpack the STEP 7 project with integrated ProTool project with all the associated subdirectories. You can then use the SIMATIC Manager and integrated ProTool to open and process the extracted project.

MP170, ProTool/Lite, ProTool/Pro, Clean, Inoperable touch, Touch screen

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