ViewDraw for Actel Schematics Tips

Adding and Removing Ports from an Existing Schematic

You may wish to add or remove ports from an existing schematic. To do so:

1. From the Libero Project Manager, right-click the symbol and select Delete from Disk and Project.

2. In ViewDraw, open your schematic and select Add/remove ports.

3. Click Save and Check.

4. Re-create the symbol from within the Libero Project Manager.

5. Update the schematics, instantiating the modified symbol.

Naming Conventions

• Project names must be less than 8 characters. For example: my_top

• Do not use spaces in:

• Project names

• Instance names

• Net names

• Port names

• Do not use any special characters in any of your naming, such as: ~ ! @ # $ % ^ & * ( ) = + { } | \ / < > ? ` ‘ “ “, .  or spaces.

• The tool does not support “inverted” net property.

• If you want to rip out scalar bits from a bus, use [] for scalar bit naming. For example, Bus[15], Bus[14], …, Bus[0].

• Do not use numbers at the beginning or the end of any names.
  Scalar bit Bus1[15] of Bus1[15:0] can be confused with Scalar bit Bus11[5] of Bus11[15:0] during netlist generation.

• If you want to use numbers to distinguish related nets, use numbers followed by letters at the end, for example: NET1N, or Bus1A[15:0].

• Do not use naming “Bus[0:3][0:3]” to implement scalar bits. The second bus dimension is not supported. Instead use: Bus[00], Bus[01]…, Bus[10], Bus[11]….

Using Connectors and I/O Pads

• Use hierarchy connectors in any schematic design for any external ports and any ports of sub-modules.

• You can insert I/O pads automatically by running Synthesis or Optimize & Insert Pads from Libero IDE. For schematic designs, which only use Actel primitives (no HDL blocks), you can manually insert all I/O pads. This is in case you do not want to go through the synthesis flow.

Hierarchical Connectors with I/O Pads

Design Flow

• To recreate a symbol for a specific block:

1. Delete all the symbol instantiations from the block’s parent level

2. In the File Manager, delete the symbol from the Block Symbol Files folder

3. Delete the symbol file from your hard disk in the \viewdraw\sym folder

4. Make the desired modifications to the block

5. In ViewDraw for Actel, from the File menu, choose Save + Check

6. From Libero IDE, select the Design Hierarchy tab. Right-click the symbol and select Create Symbol from the menu

• Check the basic connectivity of your schematic from Libero IDE. Right-click the schematic file in the File Manager, and select Check Schematic.