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Convert Menu -- Input and ASCII Output

The !set keywords below affect the format conversion when importing data from a file. Many of these variables have counterpart buttons in the Conversion - Import panel from the Convert Menu. The functionality also applies in many cases when input is being read in the Edit command and similar.

AutoRename
Value: boolean.
When set, when reading archive files and a cell is encountered with the same name as a cell already in memory, the new cell name is automatically changed to avoid a clash. Thus, the Merge Control pop-up never appears when this variable is set. The new name has an added suffix ``$N'' where N is an integer. When this is set, the alias file (if enabled) is never updated. A warning is added to the log file when a cell name is changed. This is part of a more general cell name mapping capability (see 9.1).

NoAskOverwrite (boolean)
Value: boolean.
If a disk file is opened which contains a cell with the same name as one already in memory, and AutoRename is not set, the default behavior is to produce a Merge Control pop-up which gives the user control over how to proceed. If this variable is set, then the pop-up will not appear, and the default action will be taken. The default action can be specified with the NoOverwritePhys and NoOverwriteElec variables.

$\textstyle \parbox{4in}{
{\sf NoOverwritePhys}\\
{\sf NoOverwriteElec}}$
Value: boolean.
These control the default behavior when a cell from a file being read conflicts with the name of a cell already in memory. The default behavior is for the cell from the file to overwrite the cell in memory. If NoOverwritePhys is set, the physical part of the cell in memory will not be overwritten, and the physical part of the cell in the file will be ignored. Similarly, if NoOverwriteElec is set, the electrical part of the cell in memory will be preserved, and the electrical part of the cell from the file will be ignored.

MergeInput
Value: boolean.
When this variable is set, boxes are merged together, if possible, as files are being read in. Overlapping boxes are clipped and/or merged. Objects (not subcells) that are coincident with an identical object will be deleted. This applies to all geometrical objects and not just boxes. Merging applies to conversions as well as cells being read with the Edit command.

The merging of boxes is suppressed if the NoMergeBoxes variable is set. Coincident boxes will still be deleted, however.

NoPolyCheck
Value: boolean.
When this boolean variable is set, the reentrancy test for polygons is skipped while an input file is being read. The default behavior is to check each polygon for potentially troublesome geometry specification while the polygon is being created.

NoCoincCheck
Value: boolean.
When set, testing for coincident objects (but not subcells) is skipped while reading input. Coincident subcells are always reported in the log file. This has no effect on the merging of coincident objects if the MergeInput variable is set.

NoCheckEmpties
Value: boolean.
When set, there is no checking for empty cells as an input file is being read, and the pop-up that normally appears when a file is opened for editing if there are empty symbols in the hierarchy is suppressed. An ``empty symbol'' is a symbol that contains no physical or electrical objects or subcells. It is possible to check for empty symbols at any time with the !empties command.

NoReadLabels
Value: boolean.
When this variable is set, text label elements will not be read from archive files in physical mode. This may improve efficiency if the user is concerned with physical layout data only. In multi-pass read operations, such as skeleton mode and when using the hierarchy context structure, the variable state should be the same when reading the initial context as when reading geometry, otherwise cell bounding boxes may not be accurate during the geometry read operation.

LayerList
Value: string.
This can be set to a space-separated list of layer names (see 9.3). These layers can be used for filtering when an archive file is being read or translated. Each name should be in a format which will match a layer in the file type being processed, with wildcarding allowed. This variable tracks the entry areas in the Conversion - Import and Conversion panels. Actual utilization of the layer list is controlled by the UseLayerList variable.

UseLayerList
Value: boolean or string.
This variable determines how and if the LayerList string is used when input is being read from an archive file. The layer list is used, if enabled by this variable, when

If UseLayerList in not set, the LayerList is ignored, and any layer found in the input file will be read or converted. If UseLayerList is set to a word starting with `n' or `N', layers that are listed in the LayerList will not be converted. If UseLayerList is set to a anything else (including no value) only the layers listed in the LayerList will be converted.

UseLayerAlias
Value: boolean.
When this variable is set, when reading an archive or native file, layers encountered are aliased according to entries in an internal table of aliases. This table is manipulated with the Layer Alias Editor available in the Conversion - Import and Conversion panels, or with script functions, or with the !lal command. Aliasing occurs on reading only, after the LayerList is processed, if this feature is used. Thus, a LayerList used for reading should contain the unaliased layer names. Layer aliasing applies to physical data only, under conditions equivalent to those listed for UseLayerList.

InToLower
Value: boolean.
When set, symbol names found in archive files being read that are entirely upper case will be mapped to lower case. A name that is mixed-case will not be changed. This mapping occurs for names which are not aliased in an enabled alias file. This is part of a more general cell name mapping facility (see 9.1).

InToUpper
Value: boolean.
When set, symbol names found in archive files being read that are entirely lower case will be mapped to upper case. A name that is mixed-case will not be changed. This mapping occurs for names which are not aliased in an enabled alias file. This is part of a more general cell name mapping facility (see 9.1).

InUseAlias
Value: boolean or string.
This variable enables utilization of the alias file (see 9.2) when reading from an archive file. If simply set as a boolean, i.e., to no value, the alias file will be read before the operation, and created or updated if necessary after the operation. If the variable is set to a word starting with `r' (case insensitive), then the alias file will be read before the operation and used during the operation (if it exists), but will not be created or updated after the operation. If the variable is set to a word starting with `w' or `s' (case insensitive), the alias file will not be read before an operation, but will be created or updated after the operation completes. This is part of a more general cell name mapping facility (see 9.1).

InCellNamePrefix, InCellNameSuffix
Value: string.
These variables are most simply set to a text token that is added to the beginning or end of cell name strings as archive files are being read. Modifications will not be made to cell names found in an enabled alias file. The strings can also be given in the form
/str/sub/
where str and sub are text tokens, separated by forward slash characters as shown. In this case if the characters at the beginning/end of the cell name (for prefix/suffix) match the str, they are replaced by sub. This is the same action as is used in the !rename command. The string token must match exactly -- there is no wildcarding. Either the prefix or suffix, or both, can be defined. The suffix substitution occurs after the prefix substitution. Either can match the whole cell name if one wants to change the name of a single cell. This is part of a more general cell name mapping facility (see 9.1).

NoMapDatatypes
Value: boolean.
This variable affects only the creation of new layers when a GDSII or OASIS file is read. The default behavior is to create a separate new Xic layer for each GDSII layer/datatype encountered that is not mapped in the technology file. With the variable set, all datatypes on the new GDSII layer are mapped to the same (new) Xic layer.

CifLayerMode
Value: integer 0-2.
This variable determines how Xic interprets layer directives while reading CIF files. This is the same as the layer resolution option menu in the Conversion - Import panel. Setting to 0 is the default Try Both option, 1 is the By Name option, and 2 is the By Index option.

SkeletonMode
Value: boolean.
When set, archive files will be read in ``skeleton'' mode. In this mode, the cell hierarchy but not the geometry is saved in memory. Geometry is accessed directly from the file (and cached) when needed. Skeleton mode is described in 9.12.

SkelSaveNum
Value: integer >= 0.
This controls a feature in skeleton mode that can improve processing speed. If a cell contains this many geometrical objects or fewer, it is retained in memory. The assumption is that there are small cells that are instantiated in many places, and it is more efficient to cache these cells rather than having to update from the file each time the content is needed. This variable should be set to some small number. If set to 0, this feature is effectively disabled.

NumToTxtCells
Value: integer.
When converting GDSII or CGX to a text-mode representation file, writing will stop after the number of cells given in this variable have been processed. Setting to zero will show only the file header records. If negative or the variable is unset, the entire file will be written. In the case of GDSII, such files are not back-convertible to GDSII.

OasReadNoChecksum
Value: boolean.
When set, the reader will ignore a checksum found in the OASIS file, if any. When not set, if a checksum is found, it will be compared with a computed checksum, using the method (CRC or summation) indicated in the file, and the conversion will fail if the checksums are not equal.

OasPrintNoWrap
Value: boolean.
This applies when converting OASIS input to ascii text. When set, the text output for a single record will occupy one (arbitrarily long) line. When not set, lines are broken and continued with indentation.

This variable has a corresponding check box in the Converson panel.

OasPrintOffset
Value: boolean.
This applies when converting OASIS input to ascii text. When set, the first token for each record output gives the offset in the file or containing CBLOCK. When not set, file offsets are not printed.

This variable has a corresponding check box in the Converson panel.


next up previous contents index
Next: Convert Menu Up: Xic Variables Previous: Convert Menu   Contents   Index
Stephen R. Whiteley 2006-10-23