wire_geometry

Wire geometry classes for FABulous FPGA routing structures.

This module provides classes for representing wire geometries within FPGA tiles, including simple wires and complex stair-like wire structures for multi-tile routing. It supports CSV serialization for integration with geometry files.

Classes

StairWires	A data structure representing a stair-like collection of wires.
WireConstraints	Store information on where wires arrive at the border of a tile.
WireGeometry	A data structure representing the geometry of a wire within a tile.

Module Contents

StairWires

class StairWires(name)

A data structure representing a stair-like collection of wires.

Parameters:

name (str) – The name of the stair wire structure

Variables:

• name (str) – Name of the structure

• refX (int) – Reference point x coord of the stair structure

• refY (int) – Reference point y coord of the stair structure

• offset (int) – Offset of the wires

• direction (Direction) – Direction of the wires

• groupWires (int) – Amount of wires of a single “strand”

• tileWidth (int) – Width of the tile containing the wires

• tileHeight (int) – Height of the tile containing the wires

• wireGeoms (list[WireGeometry]) – List of the wires geometries

Notes

The (refX, refY) point refers to the following location(s) of the stair-like structure:

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Depending on the orientation of the structure, rotate right by 90° to get the image for the corresponding left-right stair-like wire structure. The right stair-like structure represents a north stair; the left one represents a south stair (these being the directions of the wires).

Methods

generateEastStairWires() → None

Generate stair-like wires for east direction routing.

Creates a series of L-shaped wire segments that form a stair-like pattern for routing connections eastward across multiple tiles. Each wire starts at the right edge, goes to a stair step, then continues to the left edge.

generateGeometry(refX, refY, offset, direction, groupWires, tileWidth, tileHeight) → None

Generate the stair wire geometry based on parameters and direction.

Creates the complete stair-like wire structure by calling the appropriate directional generation method based on the specified direction.

Parameters:

• refX (int) – Reference X coordinate for the stair structure

• refY (int) – Reference Y coordinate for the stair structure

• offset (int) – Wire offset distance

• direction (Direction) – Direction of the wire routing (NORTH, SOUTH, EAST, or WEST)

• groupWires (int) – Number of wires in each group or strand

• tileWidth (int) – Width of the containing tile

• tileHeight (int) – Height of the containing tile

Raises:

InvalidPortType – If the direction is invalid for stair wires.

generateNorthStairWires() → None

Generate stair-like wires for north direction routing.

Creates a series of L-shaped wire segments that form a stair-like pattern for routing connections northward across multiple tiles. Each wire starts at the bottom edge, goes to a stair step, then continues to the top edge.

generateSouthStairWires() → None

Generate stair-like wires for south direction routing.

Creates a series of L-shaped wire segments that form a stair-like pattern for routing connections southward across multiple tiles. Each wire starts at the bottom edge, goes to a stair step, then continues to the top edge.

generateWestStairWires() → None

Generate stair-like wires for west direction routing.

Creates a series of L-shaped wire segments that form a stair-like pattern for routing connections westward across multiple tiles. Each wire starts at the right edge, goes to a stair step, then continues to the left edge.

saveToCSV(writer) → None

Save all stair wire geometries to CSV format.

Writes all individual wire geometries in the stair structure to a CSV file using the provided writer.

Parameters:

writer (csvWriter) – The CSV writer object to use for output

WireConstraints

class WireConstraints

Store information on where wires arrive at the border of a tile.

Variables:

• northPositions (list[int]) – Positions where wires arrive at the north border

• southPositions (list[int]) – Positions where wires arrive at the south border

• eastPositions (list[int]) – Positions where wires arrive at the east border

• westPositions (list[int]) – Positions where wires arrive at the west border

Methods

addConstraintsOf(stairWires) → None

Add constraints from a stair wires structure.

Parameters:

stairWires (StairWires) – The stair wires structure to extract constraints from

WireGeometry

class WireGeometry(name)

A data structure representing the geometry of a wire within a tile.

Variables:

• name (str) – Name of the wire

• path (list[Location]) – Path of the wire

Parameters:

name (str) – Name of the wire

Methods

addPathLoc(pathLoc) → None

Add a location point to the wire path.

Parameters:

pathLoc (Location) – The location point to add to the wire path

saveToCSV(writer) → None

Save wire geometry data to CSV format.

Writes the wire name and all path points with their coordinates to a CSV file using the provided writer.

Parameters:

writer (csvWriter) – The CSV writer object to use for output