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Design Rule Checking

These variables are used by the design rule checking (DRC) system and are not generated by or recognized in the XicII or Xiv feature sets. Unless stated otherwise, these settings can be controlled from the DRC Defaults panel from the Set Defaults button in the DRC Menu.

Drc
Value: boolean.
This sets whether or not the interactive rule checking is applied to objects being added to the database, tracking the state of the Enable Interactive button in the DRC Menu.

DrcNoPopup
Value: boolean.
This variable determines whether errors generated in interactive DRC will be listed in a pop-up window. If set, the messages will not pop up automatically. This initializes the state of the No Pop Up Errors button in the DRC Menu.

DrcLevel
Value: integer 0-2.
This sets the error recording level for design rule checking. If set to zero (``0'') or not set, only one violation is recorded per object. If 1, one violation of each type is recorded per object. If 2, all violations found are recorded.

DrcMaxErrors
Value: integer 0-100000.
This variable sets the maximum number of design rule violations reported in batch mode, at which point checking terminates. If set to zero or not set, no limit is imposed.

DrcInterMaxObjs
Value: integer 0-100000.
In interactive design rule checking, this variable provides a limit on the number of objects checked, to minimize the pause after an operation. If set to 0, no limit is imposed. If not set, a limit of 1000 is taken.

DrcInterMaxTime
Value: integer 0-30000.
This variable limits the time of the interactive design rule checking performed after each operation. The value is given in milliseconds. If the value is 0, there is no time limit imposed. If the variable is not set a limit of 5000 (five seconds) is assumed.

DrcInterMaxErrors
Value: integer.
This variable limits the number of violations to record during interactive testing. When the limit is reached, testing stops and control returns to the user. If set to 0, there is no limit. If not set, a limit of 100 violations is imposed.

DrcInterSkipInst
Value: boolean.
If a subcell is copied, moved, or placed, by default the subcell is tested for design rule violations if in interactive mode. Setting this variable will cause this checking to be skipped. The checking may be redundant and time consuming.

DrcChdName
Value: string.
It is possible to use a Cell Hierarchy Digest (CHD) to specify a target layout for design rule checking. This can allow DRC testing of layouts that are too large to be read into Xic normally. This value mirrors the contents of the CHD reference name text entry area in the DRC Run Control panel from the Batch Check button in the DRC Menu.

DrcChdCell
Value: string.
This variable stores an optional cell name for use as the top-level cell when a CHD is used for DRC. It mirrors the contents of the CHD top cell text entry area in the DRC Run Control panel from the Batch Check button in the DRC Menu.

DrcLayerList
Value: string.
It is possible to use only rules on certain layers, or to skip rules on certain layers, when running DRC. This variable contains a space separated list of layer names for use in the layer filtering. It mirrors the contents of the Layer List text entry area in the DRC Parameter Setup panel from the Setup button in the DRC Menu.

DrcUseLayerList
Value: boolean or string.
If this variable is set to a word that starts with `n' (case insensitive) the layers listed in the DrcLayerList variable will be skipped during DRC runs, meaning that the rules defined on the skipped layers will not be evaluated. If DrcUseLayerList is set to anything else, including to an empty string (i.e., as a boolean), then only rules on layers listed in the DrcLayerList variable will be checked during DRC runs. In this case, if the DrcLayerList is not set or empty, the filtering is not done, and rules on all layers will be checked. This variable sets, and is set by, the Check listed layers only and Skip listed layers check boxes in the DRC Parameter Setup panel from the Setup button in the DRC Menu.

DrcRuleList
Value: string.
It is possible to use only certain rules, or to skip certain rules, when running DRC. This variable contains a space separated list of rule names (technology file rule keywords) for use in this filtering. It mirrors the contents of the Rule List text entry area in the DRC Parameter Setup panel from the Setup button in the DRC Menu. Rule name matching is case-insensitive.

DrcUseRuleList
Value: boolean or string.
If this variable is set to a word that starts with `n' (case insensitive) the rules listed in the DrcRuleList variable will be skipped during DRC runs. If DrcUseRuleList is set to anything else, including to an empty string (i.e., as a boolean), then only rules listed in the DrcRuleList variable will be checked during DRC runs. In this case, if the DrcRuleList is not set or empty, the filtering is not done, and all rules will be checked. This variable sets, and is set by, the Check listed rules only and Skip listed rules check boxes in the DRC Parameter Setup panel from the Setup button in the DRC Menu.

DrcPartitionSize
Value: real number.
When this variable is set to a real number larger than 0.0, batch mode DRC initiated from the DRC Run Control panel will use a square grid of the indicated size in microns. The DRC tests will be performed sequentially in each of the grid areas that overlap the overall test area. This variable mirrors the state of the Partition grisd size entry area and None button in the DRC Run Control panel.


next up previous contents index
Next: Extraction Tech Up: Xic Variables Previous: Custom Property Filtering   Contents   Index
Stephen R. Whiteley 2017-11-08