General Description: How can I assign attributes to parts and nets in my Xilinx design?
解决方案
Attributes may be assigned by adding user-defined properties to the design with values that are accepted by Xilinx.
To declare a net property and assign it a value:
1. In the schematic page editor, select a wire. Then click the right mouse button and choose Edit Properties. Express displays the Net Properties dialog box.
2. Choose User Properties. Express displays the User Properties dialog box.
3. Choose New. Express displays the New Property dialog box.
4. Specify the new property's name, and supply its value. Then choose the OK button. Express returns to the User Properties dialog box and displays the new property and its associated value in the Properties list.
A) If the user creates an XNF file from Express, the net property name may be any string you need to document the attribute. For example, use the following property name and associated value to place a timing name attribute on a net:
Name: my_time_name Value: TNM=group1
B) If the user creates an EDN file from Express, the net property name must be the name of the attribute. For example, use the following property name and associated value to define a pad location constraint:
Name: TNM Value: group1
5. Choose OK twice to exit the dialog boxes and return to the schematic page editor.
To assign a hierarchical block or part property value
1. In the schematic page editor, select a hierarchical block or part instance. Click the right mouse button and choose Edit Properties. Express displays the Edit Hierarchical Block dialog box or the Edit Part dialog box respectively.
2. Choose User Properties. Express displays the User Properties dialog box.
3. Choose New. Express displays the New Property dialog box.
4. Specify the new properties name, and supply its value. Then choose the OK button. Express returns to the User Properties dialog box and displays the new property and its associated value in the Properties list.
A) If the user creates an XNF file from Express, the net property name may be any string you need to document the attribute. For example, use the following property name and associated value to define a pin location constraint:
Name: pin_location Value: LOC=P41
B) If the user creates an EDN file from Express, the net property name must be the name of the attribute. For example, use the following property name and associated value to define a pin location constraint:
Name: LOC Value: P41
5. Choose OK twice to exit the dialog boxes and return to the schematic page editor.