Siemens SIMATIC TD 200, Руководство пользователя

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D-16
SIMATIC TD 200 Operator Interface
C79000-G7076-C272-01
If an embedded value is set to allow editing, you must design your S7-200 program
to check the edit-notification bit. When the embedded value is modified by the
user, your program must read the value and take any necessary action with it.
!
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 Statement List
//Using the edit-notification bit to copy
// the edited value, and then resetting
// the notification bit.
//
LD V21.2 // When the operator edits the embedded
R V21.2, 1 // value, reset the bit and copy the edited
MOVWVW23,VW250 // value to the variable location.
//
LD SM0.0 // On each scan ...
MOVWVW250,VW23 // copy the variable to the location of the
// embedded value.
SM 0.0
MOV_W
EN
OUT
VW23 VW250
IN
Network #
MOV_W
EN
OUT
VW250 VW23
IN
V21.2 V21.2 1
R
Network #
Figure D-15 Sample Program for Using the Edit-Notification Bit
TD 200 Parameters and Messages