Micromod MOD: 30ML Functions Data Base Reference - Manual (Page 12)

MOD 30ML Functions
DISPLAY BLOCK
2.2.1 Display Block Operation
Moving Between and Within Displays
One option for moving between user displays is to press the tag key (the default action) to
advance to the next display, as defined by a list in the DIF (Display Interface) block. The
display list may also be accessed using a DIF block input for remote selection of a display.
Navigation within a display is defined within the scripts written for this block. User displays
can be exited to go to an alarm, other user, or device displays using the TAG key. In all
cases the current display state and display field assignments are preserved permitting you to
return to the display 'as left' unless the entry or exit display script changes it.
Display Inputs and Formats
Display block inputs can be given ASCII names for identification within the block and can be
assigned specific line (alphanumeric) and/or bar graph display formats for display purposes.
Display format information is configured separately and multiple inputs can be assigned the
same format. Inputs and local attributes not assigned a display format use default rules when
put on the display. Display block inputs provide input or output connections, local variables
for user scripts, calculated outputs, or recipe data for use elsewhere.
Basic Display Block Configuration
Initial values for local or remote data to each display field are pre-assigned. In the simplest
use of the display block, no further configuration is done (with the probable exception of
display formats), and different data would be viewed by navigating to a different display
block. In this case, (i.e. without a display format) no data can be changed from the faceplate.
If the data assigned to the bottom 8 character field is made writeable through a display format
using one of the standard entry methods ('immediate' or 'entry required'), the up and down
keys, and possibly the scroll key, are assigned to changing the values when the keys are
pressed.
Display State Scripting Language
The edit display scripts display uses a text editor to specify entry, exit and continuous
actions, the contents of each display field, and the function of each key using a scripting
language. This is useful where a variety of data must be available under one tag (such as the
typical pid loop display). The display can be thought of as always being in one of several user
defined states, with the current state number stored in the DSPSTATE attribute. For each
state, entry, exit and active (continuous) scripts as well as scripts for any key activity of
interest (pressed, held and released for each key) can be defined. All of these scripts are
optional, and only a subset will be appropriate for a given display state.
In addition to the 'per state' scripts, default scripts can be defined. For any condition or key
activity not covered by a script specific to the current display state, the default script will be
used. The default scripts are also optional, and any activity or condition not covered by either
a state specific or default script will generate system default action, if any, or be ignored. Any
such system default action is also optionally available in addition to a user defined script.
Active scripts are executed on each 50 msec tick as long as the display/display state is
active. Entry and exit scripts are executed only when entering or leaving a display state.
Power down and power up are special cases of entry and exit even if you end up on the
same display.
Access to tuning list blocks is provided via the TUNE statement, which when issued provides
a scroll list of the variables listed in the associated tuning list block. The TUNELIST attribute
is writeable, so that under script or host control a display block can reference any number of
tuning list blocks.
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