Section 4:
Screen Triggering
Page 16
COVER:
If the screen is configured as cover, it will be written on top of the screen previously triggered from
the other trigger word. Any parts of the display that are not used by the new screen will remain as
they were (again, kind of like Windows). Note however, that any variable fields that show through
from the previous screen cannot be accessed using the
Select
key. Only those variable fields on the
cover screen can be accessed.
OVERLAY:
This is identical to COVER with one exception. Any variable fields that completely show through
from the other screen can also be accessed using the
Select
key.
Methods of Screen Triggering
Triggering screens to the 2800 display can be done in three different ways. The choice is up to the system
engineer developing the application. Any of these methods can be used alone or in any combination to create a
user friendly application.
Method 1: Screen Triggering via the Next and Prev keys
The
Next
and
Prev
keys can be used to link screens together in a predefined sequence. When a screen is
created using ScreenMaker 2000K software, two linking screen numbers can be attached, one to the
Next
key
and one to the
Prev
key.
!
If a value of zero is set for the link number then the key will be ignored.
!
If a legal screen number is set then pressing the key will cause the link number to be written to screen
Trigger Word 1 resulting in the screen being displayed.
Method 2: Screen Triggering via Data Set field
As discussed previously, the 2800 will continuously monitor both screen trigger words. The Data Set field can be
used to trigger a screen by placing the desired screen number into a trigger word. This allows for a simple way to
create menu screens.
Method 3: Screen Triggering via the Function keys
The four function keys can be independently configured within each screen to control a particular bit or word in the
Drive. Function keys can also be configured to act as a screen trigger that can control either or both screen trigger
words. When a configured function key is pressed it can:
!
close a screen by writing a zero to the appropriate screen trigger word.
!
open a new screen by writing the screen number to the appropriate screen trigger word.
!
leave either screen trigger word unaffected.
Note:
This feature is available only when the CLEAR or COVER screen attribute is selected. The function keys
are not operable when the OVERLAY screen attribute is selected.
PM2800U3K Revision 4
