The DRC Menu contains commands which control checking of design rules. The menu is accessible only in physical mode, and design rule checking can only be applied in physical mode. Xic has the capability of checking for design rule violations as any object is created or modified, and for checking regions and cells interactively or in batch mode. The algorithm fully supports non-Manhattan geometry. Design rules are provided in the technology file, or interactively using the Edit Rules command.
The table below lists the commands found in the DRC Menu, and supplies the internal command name and a brief description.
| DRC Menu | |||
| Label | Name | Pop-up | Function |
|---|---|---|---|
| Setup | limit | DRC Parameter Setup | Set limits and other parameters |
| Set Skip Flags | sflag | none | Set skip flags |
| Enable Interactive | intr | none | Set interactive DRC |
| No Pop Up Errors | nopop | none | No interactive errors list |
| Batch Check | check | DRC Run Control | Initiate DRC run |
| Check In Region | point | none | Test rules in region |
| Clear Errors | clear | none | Erase error indicators |
| Query Errors | query | none | Print error messages |
| Dump Error File | erdmp | none | Dump errors to file |
| Update Highlighting | erupd | none | Update highlighting from file |
| Show Errors | next | sub-window | Sequentially display errors from file |
| Create Layer | erlyr | none | Write highlight error regions to objects on layer |
| Edit Rules | dredt | Design Rule Editor | Edit rules for layers |
After a check is performed, violating objects are shown on-screen with the border highlighted, and a highlighting border is drawn around the test region containing the error. These objects are not removed from the database. It is up to the user to fix or ignore errors as they are indicated.
Presently, the indication of a violation is not saved as the cell is written.
Design rules are specified in the technology file, or with the Design Rule Editor made visible with the Edit Rules button in the DRC Menu. The rules are specified by a keyword, followed by an optional source region specification, followed by parameters. In addition to the built-in rule primitives to be described, a capability exists for users to define specialized or more complex tests.