Siemens S7-200 System Manual page 86

Using the Text Display Wizard to Configure the S7-200 CPU for Your Text Display (TD) Device
4.4 Configuring the Screens for the Text Display Device
When you embed a string variable in a TD alarm or screen, the Text Display wizard shows
the embedded variable occupying 4 character spaces (or 2 Chinese characters) for the
variable. These 4 spaces are the right-most 4 characters of the text string. If you want to
have the text adjacent to other text, that is, to the left of the variable, the characters in the
string need to be left-justified and padded with spaces to place the text in the proper position
on the display.
For example: Assume that we want to show the pump status and that status is either "Pump
OK" or "Pump High Temp". The screen display shows the word "Pump" followed by a string
variable which is set to either "OK" or "High Temp". You set up the display in the Text
Display wizard like this:
Pump _ _ _ _ _ _
The underlines are blank spaces, and the squares are the embedded variable (which takes
up 4 character spaces). You can create 2 strings that you copy into the variable based on
the current pump status. These strings are "OK" and "High Temp". These strings are
displayed in the figure below.
Figure 4-20
The right-most character of the "OK" string is placed in the right-most position of the
embedded variable. Since the string is only 2 characters, it displays on the right side of the
display where the embedded variable is placed.
To make the "OK" string display next to "Pump", simply add blank spaces to the "OK" string
to match the length of the other string. The "OK" string would become "OK ". Now the string
is displayed in the figure below.
Figure 4-21
The figure below shows how to create the two strings using the STR_CPY command. Note
how the "OK" string is padded with blank spaces to left justify the characters on the TD
display.
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Embedded String Variable
Embedded String Variable with Blank Spaces
Text Display (TD) User Manual
System Manual, 08/2008, A5E00765548-03