Adding Attributes

Attributes are instructions placed on symbols or nets in an FPGA or CPLD schematic to indicate their placement, implementation, naming, directionality, and so forth. You can find the list of attributes that you can place on the components in your Viewlogic schematic in the Libraries Guide.

To assign attributes to nets, buses, components, or pins, complete the following steps. You must open the Net Properties, Component Properties, or Pin Properties dialog box, represented in the “Adding Attributes to a Pin” figure.

1. Open the Properties dialog boxes by either double-clicking the left mouse button on the item or single-clicking the right mouse button on the item and selecting Properties.
   
   
2. Under the Attributes tab, fill in the Name and Value fields. For example, an attribute on a symbol pin would be as follows.
   
   Name: PINTYPE
   
   Type: IN
   
   
3. To make this attribute invisible, change the Visibility field to Invisible. Click on Set to accept the attribute.
   
   
4. After you have added all the needed attributes, click on OK.
   
   

   Figure 3.13 Adding Attributes to a Pin

5. To reposition visible attributes, select the attribute only with a single left mouse button click. Click and drag with the left mouse button to the desired location.