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Forms Reference

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This chapter describes the forms in the Virtuoso Space-based Router.

• Power Routing Form
  • Power Routing - Pad Ring tab
  • Power Routing - Core Ring tab
  • Power Routing - Block Ring tab
  • Power Routing - Stripes tab
  • Power Routing - Cell Rows tab
  • Power Routing - Pin To Trunk tab
  • Power Routing - Vias tab
  • Power Routing - Tie Shield tab
• Power Routing Options Form
  • Power Routing Options - Pad Ring tab
  • Power Routing Options - Core Ring tab
  • Power Routing Options - Block Ring tab
  • Power Routing Options - Stripes tab
  • Power Routing Options - Cell Rows tab
  • Power Routing Options - Pin To Trunk tab
  • Power Routing Options - Vias tab
  • Power Routing Options - Setup tab
• Power Routing Scheme Manager
  • Power Routing Scheme Manager - File tab
  • Power Routing Scheme Manager - Compare tab
  • Power Routing Schemes Compare Result
• VSR Preset Forms
  • VSR Save Preset Form
  • VSR Delete Preset Form

Power Routing Form

The Power Routing form has tabs enabling you to set up options for each power routing operation.

Name - the scheme name for the power routing operation.

Edit - enables you to view or change the scheme definition.

Manager- displays the Power Routing Scheme Manager form.

Route - executes power routing with the options in the scheme.

Power Routing - Pad Ring tab

Pad Ring routing adds a ring between pad instances on the periphery of the design.

Related Topics

Using the Pad Ring Form

Pad Ring Environment Variables

Power Routing Options - Pad Ring tab

Power Routing - Core Ring tab

Core Ring routing adds a ring around the core of a design that is surrounded by pad instances.

Nets Ordering

Selected Nets - adds the select nets to the Nets Ordering section.

Related Topics

Using the Core Ring Form

Core Ring Environment Variables

Power Routing Options - Core Ring tab

Power Routing - Block Ring tab

Block Ring routing adds rings around block instances.

Nets Ordering - order the nets for the core rings.

Selected Nets - adds the selected nets to the Nets Ordering section.

Blocks

Style - block ring style.

	Adds separate rings around each block.
	Adds a shared ring around all blocks.

Related Topics

Using the Block Ring Form

Block Ring Environment Variables

Power Routing Options - Block Ring tab

Power Routing - Stripes tab

Stripes routing adds net stripes at regular intervals.

Nets Ordering - order the nets for the stripes.

Selected Nets - adds the selected nets to the Nets Ordering section.

Region - the region in which to add the stripes.

Entire Cell View - uses the current place and route boundary (prBoundary) for the design. If no routing regions are given, and core rings exist, the core rings become the bounds for the stripes. If no routing regions are given, and core rings do not exist, stripes will cover the entire design. More than one routing region can be given.

View Area Only - uses the current zoom area for routing. If the zoom area is outside the prBoundary, a warning is issued.

A Selected Boundary - uses a selected boundary for routing. The boundary can be either a cluster boundary or an area boundary. However, you can select only one boundary at a time for routing. If you select more than one boundary, a warning is issued. If the selected boundary is outside the prBoundary, a warning is issued.

Custom Area - allows you to specify the region by doing one of the following.

Enter the values using the spin boxes for the lower-left (xLo, yLo) and the upper-right (xHi, yHi) coordinates for the region.

Click Create. Then draw the region in the workspace by dragging a rectangle from a lower-left coordinate to an upper-right coordinate. The coordinate positions are automatically entered in the form.

Related Topics

Using the Stripes Form

Stripes Environment Variables

Power Routing Options - Stripes tab

Power Routing - Cell Rows tab

Cell Row routing adds straps along aligned pins of standard cells.

Region - area in which to add the standard cell straps.

Entire Cell View - use the current place and route boundary (prBoundary) for the design.

If no routing regions are given, and core rings exist, the core rings become the bounds for the cell rows. If no routing regions are given, and core rings do not exist, cell rows will cover the entire design. More than one routing region can be given.

View Area Only - use the current zoom area for routing. If the zoom area is outside the prBoundary, a warning is issued.

Selected Boundary - use a selected boundary for routing. The boundary can be either a cluster boundary or an area boundary. However, you can select only one boundary at a time for routing. If you select more than one boundary, a warning is issued.

If the selected boundary is outside the prBoundary, a warning is issued.

Custom Area - allows you to specify the region by doing one of the following.

Enter the values using the spin boxes for the lower-left (xLo, yLo) and the upper-right (xHi, yHi) coordinates for the region.

Create - enables you to draw the region in the workspace by dragging a rectangle from a lower-left coordinate to an upper-right coordinate. The coordinate positions are automatically entered in the form.

Related Topics

Using the Cell Rows Form

Cell Row Environment Variables

Power Routing Options - Cell Rows tab

Power Routing - Pin To Trunk tab

Pin-To-Trunk routing allows you to add connections from the power pins of pad or macro instances to existing rings and rails. A macro instance is defined as any instance whose area is greater then 90 percent of the entire cell view area.

Related Topics

Using the Pin To Trunk Form

Pin To Trunk Environment Variables

Power Routing Options - Pin To Trunk tab

Power Routing - Vias tab

Vias routing adds vias for interlayer connection at intersections of rings, rails, stripes, straps, and cell rows, or between instance pins and stripes.

Via Locations - inter-layer connections can take place at one of the following.

Intersection of All Rings, Stripes, and Cell Rows - adds vias at the intersections of all rings, stripes and cell rows.

Selected Instances - adds vias between stripes and the pins of selected block instances.

Pin Layer - determines the layer to which the via should be inserted.

Related Topics

Using the Vias Form

Vias Environment Variables

Power Routing Options - Vias tab

Power Routing - Tie Shield tab

Ties shield wires to shield nets in the design.

Tie Frequency- distance between the ties.

Shield - the distance between the shield ties.

Coax - the distance between the coax shield ties.

Route - executes the tie shield operation.

Related Topics

Using the Tie Shield Form

Tie Shield Environment Variables

Power Routing Options Form

The Power Routing Options form has tabs enabling you to set up options for changing the scheme definition of each power routing operation.

Name - the scheme name you want to define.

Manager- displays the Power Routing Scheme Manager form.

Rename - renames the scheme to the name entered in Name field.

Copy - copies the scheme to a new name. The default name is the original scheme name with _n, where n is a number, automatically appended.

Delete - deletes the current scheme. You cannot delete the Default scheme.

Power Routing Options - Pad Ring tab

The Pad Ring tab of the Power Routing Options form lets you specify pin layers and pin types to which to connect pad rings for the scheme.

Specified Pin Layers - the pin layers you want to connect.

Deselecting the check box routes pad rings on all layers in the list. Environment variable: proutePadRingAllLayers

Selecting the check box routes pad rings on the layers you highlight in the list box. Environment variable: proutePadRingLayers

Pin Types - pin types to which you want the pad rings to connect.

Rail Pins - pins that traverse a pad. Environment variable: proutePadRingRailPins

Edge Pins - pins on the edge of the pads. Environment variable: proutePadRingEdgePins

Related Topics

Using the Pad Ring Form

Pad Ring Environment Variables

Power Routing - Pad Ring tab

Power Routing Options - Core Ring tab

The Core Ring section of the Power Routing Options form lets you specify the core ring location and configuration for the scheme.

Ring Location

Centered Between Core and Pads - creates a ring between the core area of the design and the surrounding pad instances. Environment variable: prouteCoreRingRingAtCenter

Relative To - route the core ring relative to one of the following. Environment variable: prouteCoreRingRelativeTo

Core (outside) places the core ring relative to the outside the core of the design. Environment variable: prouteCoreRingCoreClearance

I/O Pads (inside) places the core ring relative to the inside of the pads. Environment variable: prouteCoreRingPadClearance

Specified Region (inside) places the core ring inside the region. Environment variable: prouteCoreRingInAreaClearance

Specified Region (outside) places the core ring outside the region. Environment variable: prouteCoreRingOutAreaClearance

Coordinates - allows you to specify the region by either using the spin boxes for the lower-left (xLo, yLo) and the upper-right (xHi, yHi) coordinates for the region or dragging a rectangle around the region. Environment variables: prouteCoreRingRTXLo, prouteCoreRingRTYLo, prouteCoreRingRTXHi, prouteCoreRingRTYHi

Clearance - the clearance between the core ring and the boundary.

Routing Configuration

Horizontal Routing Layer - the horizontal routing layer for the core ring. Environment variable: prouteCoreRingHorizLayer

Vertical Routing Layer - the vertical routing layer for the core ring. Environment variable: prouteCoreRingVertLayer

Routing Style for multiple core rings. Environment variable: prouteBlockRingLattice

Ring Clearance - the minimum spacing between the power/ground nets in the core ring. Environment variable: prouteBlockRingNetClearance

Ring Width - the total width for each power/ground net. Environment variable: prouteBlockRingNetWidth

Related Topics

Using the Core Ring Form

Core Ring Environment Variables

Power Routing - Core Ring tab

Power Routing Options - Block Ring tab

The Block Ring section of the Power Routing Options form lets you specify the ring and routing configuration for block rings.

Ring Configuration

Routing Style for Single Ring Around Multiple Blocks Environment variables: prouteBlockRingContour, prouteBlockRingChannels

	Adds block rings in a rectangular shape around the group of blocks.
	Adds block rings contoured around the group of blocks.
	Adds block rings in a rectangular shape around the group of blocks with rails in the channels between blocks.
	Adds block rings contoured around the group of blocks with rails in the channels between blocks.

Block Clearance - clearance of the block rings to the prBoundary of the block. Environment variable: prouteBlockRingBlockClearance

Routing Configuration

Horizontal Routing Layer - for the block ring. Environment variable: prouteBlockRingHorizLayer

Vertical Routing Layer - for the block ring. Environment variable: prouteBlockRingVertLayer

Routing Style - the style for multiple block rings. Environment variable: prouteBlockRingLattice

The options are:

Ring Clearance - the minimum spacing between the power/ground nets in the ring. If the specified Ring Clearance value is greater than the indicated label, the label color is black; otherwise, the color is red. Environment variable: prouteBlockRingNetClearance

Ring Width - the total width for each power/ground net. If the specified Ring Clearance value is greater than the indicated label, the label color is black; otherwise, the color is red. Environment variable: prouteBlockRingNetWidth

Related Topics

Using the Block Ring Form

Block Ring Environment Variables

Power Routing - Block Ring tab

Power Routing Options - Stripes tab

The Stripes section of the Power Routing Options form lets you specify the placement and configuration of the horizontal and vertical stripes.

Horizontal Stripes - choose to create horizontal stripes.
Environment variable: prouteStripesHorizDir

Step Increment - value to separate the horizontal stripes. Environment variable: prouteStripesYStep

Routing Layers - horizontal stripes are routed on the highlighted layers. Environment variable: prouteStripesHorizLayers

Vertical Stripes - choose to create vertical stripes.
Environment variable: prouteStripesVertDir

Step Increment - value to separate the vertical stripes. Environment variable: prouteStripesXStep

Routing Layers - vertical stripes are routed on the highlighted layers. Environment variable: prouteStripesVertLayers

Stripe Configuration

Pin Clearance - the clearance required between signal pins and stripes. Environment variable: prouteStripesPinClearance

Net Clearance - the minimum spacing required between the power/ground nets within a stripe. Environment variable: prouteStripesNetClearance

Net Width - the total width for each routed net. Environment variable: prouteStripesNetWidth

Minimum Stripe Length - minimum length for the stripe. Environment variable: prouteStripesMinLength

Relative Start Location

Offset from either the Design Boundary, the design Origin, or the Routing Area (the Routing Regions given in the Power Router Stripes form). Environment variable: prouteStripesOffsetFrom

Left - the X location of the first vertical stripe. Environment variable: prouteStripesLeftOffset

Bottom - the Y location of the first horizontal stripe. Environment variable: prouteStripesBottomOffset

Relative To - stripes are measured relative to the Edge of Stripe (left edge for vertical stripes and bottom edge for horizontal stripes), or the Center Line of Stripe. Environment variable: prouteStripesCenterLine

Related Topics

Using the Stripes Form

Stripes Environment Variables

Power Routing - Stripes tab

Power Routing Options - Cell Rows tab

The Cell Rows section of the Power Routing Options form lets you specify routing layers, the cell row strap boundary, and whether the cell row straps should be extended to the nearest power rail.

Specified Routing Layers - the routing layers you want to connect.

Deselecting the check box routes pad rings on all layers in the list.

Selecting the check box routes pad rings on the layers you highlight in the list box. Environment variable: prouteCellRowLayers

Boundary Rule

End of Row - routes cell row straps to the end of the defined rows. Environment variable: prouteCellRowRowEnd

Last Cell in Row - routes cell row straps to the last cell in the row.

Extend Straps to Rails - extends the cell row straps to the nearest power rail.
Environment variable: prouteCellRowExtend

Related Topics

Using the Cell Rows Form

Cell Row Environment Variables

Power Routing - Cell Rows tab

Power Routing Options - Pin To Trunk tab

The Pin To Trunk section of the Power Routing Options form lets you specify pin layers, trunk layers and connection rules.

Specified Pin Layers - the pin layers you want to connect.

Deselecting the check box routes pad rings on all layers in the list. Environment variable: proutePinToTrunkAllLayers

Selecting the check box routes pad rings on the layers you highlight in the list box. Environment variable: proutePinToTrunkLayers

Specified Trunk Layer

Deselecting the check box connects all trunk layers. Environment variable: proutePinToTrunkSpecTLayer

Selecting the check box restricts pin-to-trunk connections to the trunk layer you choose in the pull down layer list. Environment variable: proutePinToTrunkTrunkLayer

Connection Rules

Minimum Trunk Width - specifies the minimum trunk width for a trunk to be connected to a pin. Environment variable: proutePinToTrunkMinTrunkWidth

Minimum Wire Width - specifies the minimum wire width for a wire to connect from a pin to a trunk. Environment variable: proutePinToTrunkMinWireWidth

If you did not specify a trunk layer, the numbers to the right of the spin boxes are the largest minWidth of all the Specified Pin Layers. If you then set a Minimum Wire Width value that is smaller than the number to the right of the spin box, you are likely to violate the minWidth on layers with smaller minimums. Best practice is to set a value greater than or equal to this number, in which case the number is black.

Maximum Wire Width - specifies the maximum wire width for a wire to connect from a pin to a trunk. Environment variable: proutePinToTrunkMaxWireWidth

Pin-to-Trunk uses the largest wire width that does not exceed the Maximum Wire Width or the width of the pin.

If you did not specify a trunk layer, the number to the right of the spin box is the smallest maxWidth of all the Specified Pin Layers. If you then set a Maximum Wire Width that is larger than this number, you are likely to violate the maxWidth on layers with smaller maximums. Best practice is to set a value less than or equal to this number, in which case the number is black.

Related Topics

Using the Pin To Trunk Form

Pin To Trunk Environment Variables

Power Routing - Pin To Trunk tab

Power Routing Options - Vias tab

The Vias section of the Power Routing Options form lets you specify layers and cut array types.

Layers - that you want to connect.

Layer Range - deselecting the check box inserts vias to connect all layers.

Selecting the check box inserts vias to connect a range of metal layers. Environment variable: prouteViaInsertionLayerRange

Minimum and Maximum - pull down menus enable you to choose the bottom and top layers, respectively, to connect. Environment variables: prouteViaInsertionMinLayer, prouteViaInsertionMaxLayer

Cut Array - the type of cut array.

Square - specifies a square cut array for each via, with an equal number of rows and the number of columns. However, the cut array might not be square in size, depending on spacing rules. If the minAdjacentViaSpacing rule is set, then the spacing of the cuts can be different in the X and Y directions, producing a cut array that is rectangular in dimension.

Rectangular - specifies that the maximum number of rows and columns for the cuts be used for the available space.

Specified Array Size - inserts vias with cut arrays of a specific dimension. If the cut array with these dimensions cannot fit within a via area, no via is created for that metal intersection.

Environment variable: prouteViaInsertionCutArray

Rows and Columns - for the specified array size. Environment variables: prouteViaInsertionRows, prouteViaInsertionColumns

Related Topics

Using the Vias Form

Vias Environment Variables

Power Routing - Vias tab

Power Routing Options - Setup tab

Determines the packages available in the scheme.

Scheme Packages - the packages included in the named scheme.

Pad Ring

Core Ring

Block Ring

Stripes

Cell Rows

Pin To Trunk

Vias

Related Topics

Setting the Packages for the Scheme

Power Routing Scheme Manager

The Power Routing Scheme Manager enables you to load, save, and compare schemes.

Power Routing Scheme Manager - File tab

Name - the name of the file containing the schemes in the Name field.

Browse - alternatively, you can use this button to select the file containing the schemes.

Load - loads all the schemes in the file into the power routing scheme database

Save - saves the selected schemes to the given file name. If you save schemes to an existing file, the original contents of the file are removed and replaced by the newly saved schemes.

Power Routing Scheme Manager - Compare tab

Schemes - the schemes you select to compare from the drop down boxes. Click to compare specific packages within the schemes.

Compare - displays the Power Routing Compare Result form.

Power Routing Schemes Compare Result

The first column lists the package options that have different values in the two packages. The Total number of Differences for the two packages also displays.

The second column lists the option data for the indicated scheme.

The third column lists the option data for the indicated scheme, so you can compare the two schemes side by side.

Related Topics

Managing Schemes

VSR Preset Forms

This section describes the field descriptions of the following VSR Preset forms:

• VSR Save Preset Form
• VSR Delete Preset Form

VSR Save Preset Form

• Label in Toolbar
  Lets you specify a label for the preset file. You can also select a preset file from the drop-down list. When a preset file is selected, all other fields of the VSR Save Preset form are automatically populated with the keywords information available in the selected preset file. This is a mandatory field.
• File Name
  Lets you specify a name for the preset file to save all override constraints and environment variable values to a single file. This is also a mandatory field.
• Directory
  Lets you select the location where you want to save the preset file. You can select one of the following locations:
  • Current Virtuoso Invoking directory (./.cadence/dfII/ia/presets)
  • $HOME (~/.cadence/dfII/ia/presets)
  • $CDS_PROJECT ($CDS_PROJECT/dfII/ia/presets)
• Create Toolbar Icon
  Adds an icon on the Virtuoso Space-based Router Preset toolbar when the Create Toolbar Icon is selected. When deselected, the preset is added as a menu item in the VSR Load Preset drop-down menu.
• Optional Settings
  Hides or displays all the optional settings in the VSR Save Preset form. These optional settings are not mandatory and can be left blank.
• Icon File Name
  Uses the icon from the specified file name and associates it with the preset file. The associated icon is then displayed on the VSR Preset toolbar. This option is relevant only when the Create Toolbar Icon check box is selected.
• Icon Text
  Lets you specify the text that gets displayed on the toolbar icon. If icon text is not provided, the first five characters of the Label in Toolbar field are used as the text that gets displayed on the created icon.
  
  The Icon Text field has significance only when the Create Toolbar Icon check box is selected and the Icon File Name is left blank. However, if Create Toolbar Icon is deselected, the text specified in the Icon Text field is listed as a menu option in the VSR Load Preset drop-down list.
• Tooltip
  Lets you specify the text that appears as a tooltip when the mouse pointer is placed on the preset icon on the toolbar.
• Save
  Saves the current settings to a preset file for future use.
• Clear
  Clears all the fields in the VSR Save Preset form.

Related Topics

The Routing Scripts command also keep up with the values specified in the Override Constraints section of the Wire Assistant. For example, in the Wire Assistant, if you have specified the Bottom layer as M1, Top layer as M2, and have specified the Min Num Cuts value to 2, and then run the customized Tcl script using Route – Routing Scripts, the routing layers and minNumCuts values are overriden.

VSR Workspace

Preset File

VSR Delete Preset Form

• Preset Label
  Lists all the presets that are currently loaded. The presets listed in the Preset Label drop-down list correspond to the values that you specify for the preset files in the Label in Toolbar field in the VSR Save Preset form.
• File
  Displays the filename of the selected preset.
• Directory
  Displays the path to the location where the selected preset is saved.
• Active
  Displays Yes if the selected preset file is the one that was loaded last; otherwise, displays No.
  
  You can only delete a preset file for which the value in the Active field is Yes. A warning message is displayed stating that a deleted preset file cannot be restored in the current Virtuoso session.
  
  However, if you do not have the appropriate permissions to delete the selected preset file, the value in the Active field is shown as No. Also, a message is displayed stating that the preset file cannot be deleted and the Delete button is disabled, as shown in the following figure.
  
  

Related Topics

Deleting a Preset File

VSR Workspace

Preset File

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