MGC/PCB Files

MGC/PCB files are IFF files that are used exclusively for Mentor Graphics design transfers. This format is available from the Advanced Design System layout menu only, yet it enables the transfer of both schematic and layout information.

When you select the MGC/PCB export format from an Advanced Design System Layout window, both a layout and schematic IFF file are exported in a single step. The design data is exported into a standard directory tree contained in the program's project directory structure. The standard directory is called to_mgc.

The exported files are placed within this directory in a subdirectory that is named the same as the design being exported. This subdirectory contains an information file and the translated schematic and layout IFF files. Thus, if you were translating a design called test, the exported files (design_info, schematic.iff and layout .iff) would found in a directory called to_mgc/test.hpxfer.

From the Mentor Graphics Design Manager, a single command called import_hpeesof imports the schematic and layout data into Boardstation and Design Architect. This command automates to a single procedure the steps required to transfer both the schematic and the layout.

Mentor PCB products do not accept layout hierarchy, so the entire layout is flattened prior to building the Mentor layout.

Exporting MGC/PCB Files

This section outlines the procedure for translating designs into MGC/PCB format. For more information on transferring designs between the Advanced Design System and the Mentor Graphics Falcon Framework, contact your Agilent Technologies sales representative.

To export an MGC/PCB file:

1. Follow the steps as outlined in Exporting a Layout. For available options (accessed via More Options in the Export dialog box), see Export MGC/PCB Options.
2. If the option Prompt For User Message was selected, an Export MGC/PCB Options message dialog appears:
   
   Enter any messages to be included with the design transfer. This information is used only by the import_hpeesof utility (see MGC/PCB Files) and is not kept with the design.
   If you do not wish to include a message in the file, you may leave this window empty. If you want to print the message, click Print.
   To proceed with the transfer, click OK.
3. When the translation is completed, the following message window appears:
   
   Click OK to dismiss this window.
4. The IFF Export log appears:
   
   Review the log, searching for any warnings or error messages generated during export.
   The log file appears in the hpeesofeedit window by default. This window is provided as a means of viewing the file and is not intended for editing.
5. To dismiss the log window, choose File > Quit.
   

Export MGC/PCB Options

IFF File Overwrite Options

• Overwrite IFF File
  When writing to an existing file, the contents of that file are overwritten. This is the default setting.
• Append to IFF File
  When writing to an existing file, the new data is appended to the existing file.

Default Library Name For Library Parts

The name of the library to which the library parts are written. Design objectives are stored in a group that uses the same name as the project directory, but library parts are stored in either the default library hpeesoflib or a library that you specify.

Note The default library name can contain only alphabetic and numeric characters.

Output disabled instances to the IFF file

When this option is selected, if an instance is disabled in the schematic, it will still be output into the IFF file. If the checkbox is deselected (default), disabled instances will not be exported. This option can be utilized to omit certain components from being transferred to remote environments that might not support the components (e.g. disable the simulation components prior to creating an IFF file to send to Cadence, which does not have any definitions for the simulator components). Activate this option if you want to get everything. Deactivate this option if you want to filter out the unused/unwanted components.

Output ADS Item Definition properties

When this option is selected, ADS Item Definition properties are utilized to recreate the information necessary to simulate a component for ADS. For example, if you have parameters on a resistor, some Item Definition properties are created in the IFF file (e.g. R_ADS_UNIT=1), which allow the IFF importer to exactly recreate the component as it exists in ADS. However, other tools will not recognize the Item Definition parameters, and may misinterpret the properties as being separate. If library symbols are being exported to other environments that do not recognize the ADS Item Definition parameters, the option should be turned off. This option is deselected by default.

Put a space between numbers and the scalar/unit

When this option is selected, parameter values are exported as they normally appear in ADS (i.e. with a space between the number and the scalar, e.g. "1 pF"). If the checkbox is deactivated, the exporter converts the values into the IFF value specification, which is to have no space between a number and a scalar (e.g. "1pF"). Ideally, an IFF exporter should interpret either form of number, and set the value internally to whatever is normal for that environment. Some environments (e.g. Mentor Graphics) do not interpret the IFF property values in any way. For Mentor IC, this means the numbers need to have no space in them, because, when they are used within SPICE simulations, the space will cause syntax errors in the simulator. However, for Mentor Board, they require the ADS components to have a space in them, because the RF Architect ADS library is set up to expect values to have a space between a number and a scalar/unit.

Schematic Hierarchy Option

This establishes how much of the schematic hierarchy is exported:

• Current Design Only
  Write current level only. Complete design information for the current design is exported. Instance-specific information (parameter values and coordinates identifying position) is also exported. Detailed definitions of a referenced design are not exported.
• Current Design, Selected Projects and No Library Parts
  Complete design information for the current design is exported. Referenced designs that reside in a project selected for inclusion during export and are part of the current design's hierarchy are also exported. Library parts are not exported.
  This is the default setting.
• Current Design, Selected Projects and All Library Parts
  Complete design information for the current design is exported. Referenced designs that reside in a project selected for inclusion during export and are part of the current design's hierarchy are also exported. In addition, library parts are exported.

Project Hierarchy

Displays the current project. If hierarchical, all included projects are listed in the appropriate order.

Projects Included During Schematic Export

The projects for which design information will be exported. You may customize this list if the current project is hierarchical. (Note that complete layout hierarchy is always exported.)
To add a project to this list:

1. In the Project Hierarchy list, click the desired project.
2. Click the Include button. The project is added to the Projects Included list.

To include all projects, click Include All.

To Remove a project from the Projects Included list:

1. In the Projects Included list, click the entry you want to remove.
2. Click the Remove button. The project is removed from the list.

To remove all entries from the Projects Included list, click Remove All.

Prompt For User Message

When selected, a user message window appears before the transfer is initiated. This window enables you to enter any messages that you want included in the translated file. For more information about the user message, see Export MGC/PCB Options.

This option is selected as the default.