B.5 Object Properties

Object properties are properties that can be attached to objects in the timing diagram and accessed by Waveperl scripts. An object property consists of two text strings, a name (spaces not allowed) and a value (spaces allowed). Object properties allow the user to represent and store information needed by export scripts that WaveFormer Pro was not programmed to handle (e.g., data type information for signals being exported to a VHDL testbench).

To add a property to an object in the timing diagram:

•Select the Import/Export > Edit Object Properties menu option. This opens the Object Properties dialog box.

•Choose the type of object that you want to work with from the Object Type drop-down list box at the top of the dialog. This causes the names of all objects of that type to be displayed in the Object Name list box.

•Select the object to which the property is to be added.

•Type the name of the new property into the Property edit box and its value into the value edit box. An example property for a signal object might have the name VhdlType and a value of integer.

•Click the ADD button to add it to the signal.

•Click the OK button to close the dialog.

The VHDL wait script (wvhdl.epl) demonstrates how property-value pairs can be used to extend the capabilities of WaveFormer Pro. The script uses the signal properties, VHDLType, to define the type (integer, bit_vector, etc.) of stimulus signals. The user can set this property directly by choosing the the Import/Export > Edit Object Properties menu which opens a dialog with the property (it is also set indirectly when a VHDL type is selected in the Edit Signal dialog). If the VhdlType property is defined for a signal then the script assumes a type of std_logic.

NOTE: Object properties associated with a timing diagram object are supplemental to the normal state of the object. WaveFormer does not attempt to interpret object property information. It only saves the information and provides an interface for adding and changing the information. Waveperl scripts have access to object property information, and it is the script writer's job to define the meaning of object property information within a particular script.

Future versions of WaveFormer Pro will likely make use of some property names. These property names will begin with a ‘$’ to distinguish properties that are interpreted by WaveFormer Pro. For this reason, we recommend that you do NOT use property names that begin with a ‘$’ (e.g., $INTERNAL).