Sample Program For Using The Edit-Notification Bit - Siemens SIMATIC TD 200 User Manual

Caution
!
The edited (new) value that the user enters in an embedded message can be overwritten
by the value that was displayed in the message before the edit.
This could cause you to lose the newly edited value.
If you allow an embedded value to be edited, you must design your program to check the
edit-notification bit and to move and/or save the edited (new) value each time there is an
edit.
If a value is set to allow editing, you can move the cursor to the embedded value and
increment or decrement the value by using the UP and DOWN arrows. The
SHIFT-UP/DOWN arrow keys allow you to move to specific characters within the variable.
The longer you press the arrow key, the faster the value changes.
After you have changed the embedded value to the desired value, you must press ENTER.
Pressing ENTER causes the TD 200 to send the edited value to the S7-200 CPU and sets
the edit-notification bit in the format word preceding the embedded value.
Figure D-15 shows an example of how you can use the edit-notification bit. For this example,
VB21 is assumed to be the most significant byte of the first format word of the message, and
the embedded value is a word-sized value immediately following the format word (located in
VW23).
Ladder Logic
Network #
V21.2
EN
IN
VW23
Network #
SM 0.0
EN
IN
VW250
Figure D-15 Sample Program for Using the Edit-Notification Bit
SIMATIC TD 200 Operator Interface
C79000-G7076-C205-04
V21.2 1
R
LD V21.2
MOV_W R V21.2, 1
MOVWVW23,VW250 // value to the variable location.
LD SM0.0
OUT
VW250
MOVWVW250,VW23 // copy the variable to the location of the
MOV_W
OUT
VW23
TD 200 Parameters and Messages
Statement List
//Using the edit-notification bit to copy
// the edited value, and then resetting
// the notification bit.
//
// When the operator edits the embedded
// value, reset the bit and copy the edited
//
// On each scan ...
// embedded value.
D-15