recognize_vias

recognize_vias 
-lib s_libName 
[ -append {true | false} ] 
[ -cmd_file s_fileName ] 
[ -force ] 
[ -ignore_case ] 
[ -ignore_layers {s_layerName …} ]
[ -no_save ] 
[ -name_pattern s_viaExpr ] 
[ -remove_existing ] 
[ -view s_viewName ]

Description

Performs automatic via recognition by evaluating every cellview in the given library. A custom via definition is added to the technology file for each cellview that meets the via conditions listed below. If the cellview type is not a via cellview, the cell type is changed in the library.

Use of this command can change the data in your technology database file, tech.db, and should be used with caution because others in your group might also be using the file.

The recognize_vias command requires that layer definitions (change_layer) exist in the OpenAccess technology file to mark the material type and the mask number appropriately. In addition, the technology file may not already contain custom via definitions. Review and verify the technology information using the tech_info command before you load the design.

When you use this command, every cellview in the technology library is evaluated for the following conditions:

• The cellview contains three layer purpose pair headers.
• There is one cut layer.
• The other two layers are the above and below layers (based on their mask numbers) to the cut layer.
• The above layer is of material type "wire".
• The below layer is of material type "wire" or "poly".
• The above layer has one shape.
• The below layer has one shape.

The command has the following limitations:

• Does not check that the above and below shapes enclose the cut layer shapes.
• Does not define vias to P or N diffusion.

Arguments

-append {true|false}	If true, appends to a list of existing via definitions. If false, the command will check for existing via definitions in the technology library and will not run if via definitions already exist.
-cmd_file s_fileName	Writes a Tcl script of add_custom_via_def commands for each cellview that meets the via criteria instead of updating the technology file. This allows you to evaluate the vias found and remove any that have been improperly identified. You can source the script to add the via definitions.
-force	Forces vias to be recognized even when the cut layer is not completely within the two metal layers. By default, the via is only recognized when the cut layer is completely within the two metal layers.
-ignore_case	If name_pattern is set, then case is ignored when matching cellnames.
-ignore_layers {s_layerName …}
	Ignores the given layers during evaluation.
-lib s_libName	Specifies the library to scan.
-name_pattern s_viaExpr
	Automatically recognizes cellviews whose names match the given expression as via cells.
-no_save	Prevents custom via definitions and cellview changes from being saved to the library and the technology file. When you exit Space-based Router and Chip Optimizer, a dialog will appear that lets you save these changes.
-remove_existing	Removes all via definitions before starting.
-view s_viewName	Specifies the view name in the given library to scan for via cells. By default, the layout view is scanned.

Examples

The following command creates a file, via_def_cmds.tcl, of add_custom_via_def commands that can be sourced to create custom via definitions for the newTiny library.

recognize_vias -lib "newTiny" -cmd_file via_def_cmds.tcl

Related Topics

Technology Commands

add_custom_via_def

tech_info

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