This command imports PADS ASCII files from PowerPCB v5.0 or earlier. All database intelligence, such as layer names, layer structure, etc. is maintained. Reference Designators and Pin Numbers are assigned to User Data for each associated item. In addition, you have the option of automatically running a netlist comparison, to verify your artwork against your original netlist.
After importing the database, you can use VisualCAM to create and export an IPC-D-356/A netlist, export an ODB++ database, etc.
Select the File|Import|PADS ASCII command. The Import PADS ASCII File dialog box appears.
Select your desired .asc file and click Open. The Import PADS ASCII dialog box appears.
If you select the Assign Net Data To External Net Layer option, all netlist information will be imported onto a separate, External Net layer.
If you select Assign Net Data To External Net Layer, you have two additional options that allow you to automatically perform a netlist comparison: Generate New Netlist From Artwork creates a new Internal netlist from your artwork, and Run Netlist Compare automatically runs the Analysis|Netlist Compare function after you click OK.
If you do not select the Generate New Netlist From Artwork option, the original "Internal" netlist information will remain so that, if you later change your data and wish to compare against your original netlist, you can generate a new netlist and select the Preserve Existing Net Names option to more easily identify where the differences are.
Tip: If you select to generate a new netlist, the system automatically creates the netlist without presenting you with any options, such as including single point nets. If you have special requirements for generating the netlist, do not select the Generate New Netlist From Artwork option, and instead run the Tools|Netlist|Generate function after you have imported your database.
Click OK, and your database is imported. If you selected the Assign Net Data To External Net Layer option, an External Net layer is created in addition to your other layers. Viewed by itself, this layer appears to contain no data. However, this layer contains the external netlist information, and links the external net points to the appropriate top/inner/bottom layer net test points. To view the points, turn on the associated top, bottom, and inner layers, and the external net layer. The net points are displayed in four ways for easy reference:
If you selected the Run Netlist Compare option, VisualCAM automatically displays discrepancies in the Navigator, which you may use to view the errors in the workspace and print reports. If you need to change any data to fix errors, you should then re-run the Netlist Compare command to verify that the fix was accurate. Once no more errors exist, you can use the Tools|Netlist|Apply External Net Names command to apply the external net names to the database, if you wish.
