Emerson Process Management ControlWave EFM 3808 - Manual (Page 115)

CI-ControlWave EFM Installation & Operation / 2-63
If a shorter timeout of the display is needed for power savings, another timeout may be
implemented. The processor connected to the display will control the timeout. When the
timeout occurs the display will be blanked, but communications between the ARM and
display processor will still occur. The display processor will ignore posting the messages to
the screen when in the low power mode. When a key is pressed the display processor will
return to displaying information to the display.
Displays are organized into screens as follows:
Opening Screen:
User defined strings
List Selection Screen: List
Name
List Number
<Blank Line>
<Blank Line>
The List Selection screen is entered from the main opening screen by pressing the right
arrow. Once here the operator can select which list is to be viewed. The operator can
traverse though different list numbers by pressing the down arrow key. When the list to be
scrolled is shown on the display, pressing the right arrow key will bring the operator to the
Display Element screen.
Display Element Screen: <Blank
Line>
<Blank Line>
Variable Name
Variable Name
The Display Element screen is entered from the list selection screen by pressing the right
arrow. Once here the operator can view the variables in the list. Once entered the first
element of the list is displayed and then next element will be displayed after the scroll
timeout occurs. The scrolling will continue displaying the next element in the list and then
wrapping around to the beginning of the list. The down arrow key will toggle the display
through hold and scroll mode. Pressing the right arrow key will bring the operator to the
list selection screen.
Display/Keypad Assemblies are supported by Automatic Mode and Manual Mode.
In Automatic Mode a set of screens (based on the application load) are displayed. The
application programmer provides strings for the opening screen. From there the firmware is
responsible for displaying the screens and responding to key presses. Screens are fixed and
start off with an opening screen, which displays user information passed into the function
block. Users can view a list to select which list is to be scrolled. Once the list to be scrolled
has been selected, the user can scroll through the list by pressing the down arrow key. List
elements will be displayed automatically, scrolling at a predetermined rate (determined by
iiScrollTime). The user may pause on a variable by pressing the right arrow key. Pressing
the right arrow key again will cause the list to start scrolling again.
The essence of Automatic Mode is that the user can supply inputs into the function that
will determine which list can be displayed, but cannot change the menu or display. The
user is allowed to select a list and to start/stop scrolling.