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Entry type: FAQ Entry ID: 21334782, Entry date: 05/17/2005

TD200/TD200C 3.0/1.0 -- Working with the status byte

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Localizing/Evaluating status information of function keys




Troubleshooting and Handling Instructions

T1 How can I evaluate the function keys of TD200/TD200C in my program?

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Answer T1
How can I evaluate the function keys of TD200/TD200C in my program?

The status byte for the TD200 as from version V3.0 and TD200C as from version 1.0 includes the status of the function keys:

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This byte follows the enable bits for the alarms. The address of the parameterization can be defined using the TD200 wizard. The default setting is the range from VB0 to VB63. Here VB46 to VB55 is reserved for alarm enable bits. Subsequently the start address of the status byte is VB56.

Structure of the status byte of the function key statuses:

Key function Symbolic addressing Absolute addressing (status byte VB56)
X X VB 56.7
X X VB 56.6
X X VB 56.5
Arrow Left TD_Left_Arrow_Key_0 VB 56.4
Arrow Right TD_Right_Arrow_Key_0 VB 56.3
Enter TD_Enter_0 VB 56.2
Arrow Down TD_Down_Arrow_Key_0 VB 56.1
Arrow Up TD_Up_Arrow_Key_0 VB 56.0

Open the TD200 configuration in the data block of your S7-200 project file. Here you will find the memory areas you selected for the alarm enable bits and can now use them in your user program.

You can use the following Micro/WIN V4 SP1 project file to test the function keys of a connected TD200 or TD200C. For this you open the status table contained in the Micro/WIN V4 SP1 project file. After activating the table status (start test/table) you can evaluate the status of the TD200/TD200C function keys.

Attachment T1-1: T1_attachment_01.zip ( 8 KB )  

The addresses of the memory areas for alarm enable bits can be different depending on the TD200 wizard configuration.

The sample program (Attachment T1-1) is configured for Micro/WIN V4.0 SP1. The entries in the symbol table under the USER2 table were entered manually. As from Micro/WIN V4.0 SP2 the status bits of the function keys are automatically addressed symbolically by the TD-200 wizard. The entry is then in the TD_SYM_0 table. In this sample program the assignment of names for the symbolic addressing and for the status table is compatible with Micro/WIN V4.0 SP2.

The requirement for using the above-mentioned test file is that STEP 7 Micro/Win V4.0 Service Pack 1 is installed. More information on the update is available at the following link:

Topic Entry ID
STEP7 Micro/WIN V4.0 Service Pack 1 Update (V4.0.0 to V4.0.1)     19835315
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FAQ History

Change Date
FAQ revised.
Changes in the project file, new table
April 14, 2005
FAQ created March 31, 2005
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S7-200, TD200, TD200C, STEP 7 Micro/WIN V4, TD200 wizard, Wizard 

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