NAiS GT10, Technical Manual

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GT10/GT30 7.1 Switching Screens
116
7.1 Switching Screens
There are three ways to switch screens registered in the GT main unit.
7.1.1 Switching the Screen from the PLC
GT main unit screens can be switched from the PLC ladder program, by writing the
number of the screen to be displayed in hexadecimal format to the initial word of the
word device in the basic communication area.
At the same time that the screen is switched, the GT main unit writes the number of the
screen to which the display was switched in the first to third words of the basic
communication area, in hexadecimal format.
How communication is carried out between the GT main unit and the PLC (screen
switching)
GT main unit
PLC
Basic communication area / word device
First word (specifies screen no. from PLC)
Second word (usage prohibited area)
Third word (no. of screen currently displayed)
Internal PLC device
Ongoing
communication
How screens are switched
GT main unit
PLC
GT main unit
PLC
Screen No. 1
Screen No. 2
When Screen No. 2
is specified by the
PLC
the screen
switches to
No. 2
and the PLC is noti-
fied that the screen
has been switched.
Basic communication area / word device
First word, HEX 2
Second word (usage prohibited area)
Third word, HEX 1
Basic communication area / word device
First word, HEX 2
Second word (usage prohibited area)
Third word, HEX 2
Example of ladder programs
Following are basic screen display programs in FPWIN Pro and FPWIN GR.
When the PLC directs the display unit to switch screens, indicate as shown in the
programs both:
the screen to be displayed using a hexadecimal number
the destination of the screen as defined in the basic
communication area