Topic: DMD0272
Cross Reference View
The Cross Reference View provides a table of element and instruction usage information. The Cross Reference View can be opened by selecting the Tools-> Cross Reference... menu selection, or by clicking the Xref button on the Tools bar, or by the Ctrl+Y keyboard combination.
The Cross Reference View operates in one of the following modes (each
of which is discussed in more detail below):
Cross Reference mode - which operates like a database query in that the toolbar buttons define a 'query' that generates a list of elements and instructions that meet the requirements of that query.
Element Usage mode - displays ranges of elements and indicates which elements within those ranges are currently being used in the project.
Cross Reference Mode
When in Cross Reference Mode the toolbar buttons define the scope of the query and the element type constraints that will be used. The toolbar buttons are 'sticky' meaning that, to enable that button's function, left-click it once and the button will remain in the 'pressed state, left-click again to disable that button's function.
The Cross Reference Mode toolbar buttons are (from left to right) :
Cross Reference Mode enable - sets the current mode of the Cross Reference View to Cross Reference Mode
Element Usage Mode enable - sets the current mode of the Cross Reference View to Element Usage mode (see description below)
Follow Ladder Cursor - if enabled, only the topmost element in the cross reference table will follow the Ladder Edit cursor as it is moved around the Ladder View. If disabled, the cross reference table can be navigated with its cursor keys and the scroll bars.
The next group of four buttons determine
how much of the project's ladder logic will be looked at to generate the
set of cross referenced points which will then be displayed in the cross
reference table.
XRef Point Scope - limits the set of cross referenced points to the active Ladder View’s edit cursor
XRef Rung Scope - limits the set of cross referenced points to all of the instructions on the rung where the active Ladder View’s edit cursor is currently positioned.
XRef Block Scope - limits the set of cross referenced points to all of the rungs in the active Ladder View.
XRef Full Scope - the cross reference query looks at all of the code-blocks in the project.
The next set of 4 buttons are used to further refine the set of cross referenced points by filtering elements out of the list based on the element’s data-type. Left-clicking one of the buttons will enable the inclusion of that data type in the set of cross referenced points.
XRef Include BITs - include only BIT data types in the cross reference table
XRef Include NUMERICs - include only NUMERIC data types in the cross reference table
XRef Include STRUCTs - include only STRUCT data types in the cross reference table
XRef Include DEVICEs - include only DEVICE data types in the cross reference table
The final set of 2 buttons are used to further refine the set of cross referenced points by filtering elements out of the list based on the element’s access type. Left-clicking one of the buttons will enable the inclusion of elements that are used in instructions as that access type in the set of cross referenced points.
XRef Include INPUTs - include ONLY points used as INPUTS to instructions in the cross reference table
XRef Include OUTPUTs - include ONLY points used as OUTPUTS to instructions in the cross reference table
Cross Reference Mode Column Headers
Element - The element id or nickname that has been referenced in the program Note: double-click on the Element to invoke the Element Browser.
Extended info - Casting and Structure Member information are shown in the new Extended Info column.
Access Type
- along with the Input or Output or Input/Output Access Type for that
specific parameter.
Address
- The Instruction Address is a fully qualified <code-block>@<address>
string.
Instruction
- Type of instruction that contains the element
Parameter - Other additional information includes the element’s Parameter Info (where appropriate) Note: double-clicking on the entries of the Extended Info, Access Type, Address, Instruction, or Parameter fields moves the Ladder View's edit cursor to the location in the program where the element is used.
Element Usage Mode
The Element Usage Mode provides an efficient view of the memory elements that are being referenced, which are free, and whether or not they are being used in a ranged instruction. The elements are shown in groups of 8, 10, or 16 bits as determined by the current Usage Field Size setting.
The Element Usage Mode toolbar buttons are (from left to right) :
Cross Reference Mode enable - sets the current mode of the Cross Reference View to Cross Reference Mode (see description above)
Element Usage Mode enable - sets the current mode of the Cross Reference View to Element Usage mode
Follow Ladder Cursor - if enabled, only the topmost element in the cross reference table will follow the Ladder Edit cursor as it is moved around the Ladder View. If disabled, the cross reference table can be navigated with its cursor keys and the scroll bars.
Reverse Usage - toggles the display order of the elements in the range, from MSB is the left-most element -to- MSB is the right-most element.
The final set of 3 buttons are used to define the number of elements to display in each range
8 - set of usage field display to 8 elements
10 - set of usage field display to 10 elements
16 - set of usage field display to 16 elements
Element Usage Mode Display
Element - The range of elements
Range Displays - the following icons can be shown in a cell for a given element:
X - the point is used explicitly in the project
[ - the point is used at the beginning of a range of contiguous points
&emdash; - the point is implicitly used within a range, but is not referenced explicitly in the project
] - the point is used at the end of a range of contiguous points
I - the point is used both as the beginning of a range and at the end of a range.
See Also: