Customization is the need of the day. From picking an ice cream flavor to outfitting a premium car, we all want a product customized according to our needs and expectations.
Virtuoso users are no exception.
Yes, you can customize many features in the Virtuoso environment by changing values of variables that control these features. These variables stored across various .cdsenv files are shipped with each Virtuoso release and they determine how Virtuoso looks or behaves.
Traditional Methods of Setting Environment Values
Values of cdsenv variables can change during the course of using Virtuoso either through the forms with which these environment variables are associated or by updating them using the Virtuoso Command Interpreter Window (CIW).
If you want to ensure that certain values are loaded every time you launch Virtuoso, you can create a private .cdsenv file and save it in your home or work directory.
One of the biggest challenges of using these methods is the need to know and remember the names of all cdsenv variables associated with the Virtuoso tool you are using. Otherwise, you will have to look up the variable names from the default .cdsenv files shipped with Virtuoso. This can be a daunting task even for expert users, let alone the new or infrequent users.
Cdsenv Editor Changes the Picture
Introduced with the IC6.1.8 and ICADVM18.1 base releases, Cdsenv Editor lets you see a list of all Virtuoso tools and how they can be customized using cdsenv variables. You can expand each tool directory to view related cdsenv variables and edit these variables based on your needs.
To launch Cdsenv Editor, in CIW, choose Options – Cdsenv Editor or run startCdsenvEditor().
Notable Capabilities of Cdsenv Editor
Check name and value of variables
You can scroll through the tools listed in Cdsenv Editor to examine the cdsenv variables that are supported in Virtuoso.
Search for a variable name
Cdsenv Editor supports non-case-sensitive, substring search that lets you easily search for different types of cdsenv variables supported in the Virtuoso release being used. The tool is especially useful to look for a cdsenv variable when you only remember its partial name.
For example, if you want to look for a cdsenv variable that allows you to use right-click to zoom in the design, all you need to do is type mouse in the search field. All variables, values, and tool names that contain the substring mouse will be listed in the results.
Search for other information
In addition to searching for cdsenv variables by their names or by string within their name, you can perform search for all other information displayed in the editor, such as Type or Status . For example, if you search for the term modified, all modified environment variables will be listed. This information is useful in finding settings that are different from default settings in Virtuoso.
You can also search for different types of variables, such as boolean, string, or cyclic.
No need to remember valid values
If you are an expert Virtuoso user, you might already know valid values for cdsenv variables that you use frequently. However, even experts can be overwhelmed if there are several variables to update. This issue is easily taken care of in Cdsenv Editor that takes guess work out of variable settings. All valid values for the variables are visible in the editor and you can easily set the required value. The following screenshot shows valid values of a cyclic cdsenv variable.
Easily modify values
Being an editor, the main function of this tool is to let you modify the value of a selected cdsenv variable. For this, click in the Value column of the selected variable. The Value field will provide you with options to modify the values based on the type of variable. For example, if you are modifying the value of a boolean variable, the associated drop-down list lets you choose between t or nil. If the variable takes an integer value, you can either type in an integer within the valid range or use the spin box to increase or decrease the integer value. Similarly, a variable that takes string values provides a text box to let you type in a string.
Save to and load from files
Cdsenv Editor lets you save the modified variables into a .cdsenv file. You can also load the same file, or any other .cdsenv file that your CAD engineer asks you to load in the next Virtuoso session.
Revert to default values in a single click
For variables with numerical values, it is often difficult to remember the default values that were shipped with Virtuoso, especially after a long designing session. You can easily revert to default values by right-clicking a modified variable and selecting Set to default value.
Related Resource
Virtuoso Design Environment User Guide
For more information on Cadence circuit design products and services, visit www.cadence.com.
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Happy customizing.
Sucharita, Teng-Kiat Lee
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