PCB-Tools¶
Contents:
About PCB Tools¶
PCB Tools provides a set of utilities for visualizing and working with PCB design files in a variety of formats. The design files are generally referred to as Gerber files. This is a generic term that may refer to RS-274X (Gerber), ODB++ , or Excellon files. These file formats are used by the CNC equipment used to manufacutre PCBs.
PCB Tools currently supports the following file formats:
- Gerber (RS-274X)
- Excellon
with planned support for IPC-2581, ODB++ and more.
Image Rendering¶
The PCB Tools module provides tools to visualize PCBs and export images in a variety of formats, including SVG and PNG.
Future Plans¶
We are working on adding the following features to PCB Tools:
- Design Rules Checking
- Editing
- Panelization
Feature Suppport¶
Currently supported features are as follows:
| File Format | Parsing | Rendering | Unit Conversion | Scale | Offset | Rotate |
|---|---|---|---|---|---|---|
| RS274-X | Yes | Yes | Yes | No | Yes | No |
| Excellon | Yes | Yes | Yes | No | Yes | No |
| ODB++ | No | No | No | No | No | No |
PCB Tools Reference¶
rs274x — RS-274X file handling¶
The RS-274X (Gerber) format is the most common format for exporting PCB artwork. The Specification is published by Ucamco and is available here. The rs274x submodule implements calsses to read and write RS-274X files without having to know the precise details of the format.
The rs274x submodule’s read() function serves as a simple interface for parsing gerber files. The GerberFile class stores all the information contained in a gerber file allowing the file to be analyzed, modified, and updated. The GerberParser class is used in the background for parsing RS-274X files.
Functions¶
The rs274x module defines the following functions:
- read(filename)¶
Read data from filename and return a GerberFile
Parameters: filename : string
Filename of file to parse
Returns: file : gerber.rs274x.GerberFile
A GerberFile created from the specified file.
Classes¶
The rs274x module defines the following classes:
- class GerberFile(statements, settings, primitives, apertures, filename=None)¶
A class representing a single gerber file
The GerberFile class represents a single gerber file.
Parameters: statements : list
list of gerber file statements
settings : dict
Dictionary of gerber file settings
filename : string
Filename of the source gerber file
Attributes
comments: list of strings List of comments contained in the gerber file. size (tuple, (<float>, <float>)) Size in [self.units] of the layer described by the gerber file. bounds: tuple, ((<float>, <float>), (<float>, <float>)) boundaries of the layer described by the gerber file. bounds is stored as ((min x, max x), (min y, max y)) Methods
offset render to_inch to_metric write - write(filename, settings=None)¶
Write data out to a gerber file.
- class GerberParser¶
GerberParser
Methods
dump_json dump_str evaluate parse parse_raw - evaluate(stmt)¶
Evaluate Gerber statement and update image accordingly.
This method is called once for each statement in the file as it is parsed.
Parameters: statement : Statement
Gerber/Excellon statement to evaluate.
excellon — Excellon file handling¶
The Excellon format is the most common format for exporting PCB drill information. The Excellon format is used to program CNC drilling macines for drilling holes in PCBs. As such, excellon files are sometimes refererred to as NC-drill files. The Excellon format reference is available here. The excellon submodule implements calsses to read and write excellon files without having to know the precise details of the format.
The excellon submodule’s read() function serves as a simple interface for parsing excellon files. The ExcellonFile class stores all the information contained in an Excellon file allowing the file to be analyzed, modified, and updated. The ExcellonParser class is used in the background for parsing RS-274X files.
Functions¶
The excellon module defines the following functions:
- read(filename)¶
Read data from filename and return an ExcellonFile Parameters
- filename : string
- Filename of file to parse
Returns: file : gerber.excellon.ExcellonFile
An ExcellonFile created from the specified file.
Classes¶
The excellon module defines the following classes:
- class ExcellonFile(statements, tools, hits, settings, filename=None)¶
A class representing a single excellon file
The ExcellonFile class represents a single excellon file.
http://www.excellon.com/manuals/program.htm (archived version at https://web.archive.org/web/20150920001043/http://www.excellon.com/manuals/program.htm)
Parameters: tools : list
list of gerber file statements
hits : list of tuples
list of drill hits as (<Tool>, (x, y))
settings : dict
Dictionary of gerber file settings
filename : string
Filename of the source gerber file
Attributes
units (string) either ‘inch’ or ‘metric’. Methods
hit_count offset path_length render report to_inch to_metric update_tool write - path_length(tool_number=None)¶
Return the path length for a given tool
- primitives¶
Gets the primitives. Note that unlike Gerber, this generates new objects
- report(filename=None)¶
Print or save drill report
- to_inch()¶
Convert units to inches
- to_metric()¶
Convert units to metric
- update_tool(tool_number, **kwargs)¶
Change parameters of a tool
- class ExcellonParser(settings=None, ext_tools=None)¶
Excellon File Parser
Parameters: settings : FileSettings or dict-like
Excellon file settings to use when interpreting the excellon file.
Attributes
bounds coordinates hole_count hole_sizes Methods
parse parse_raw
operations — Cam File operations¶
The operations module provides functions which modify gerber.cam.CamFile objects. All of the functions in this module return a modified copy of the supplied file.
Functions¶
The operations module defines the following functions:
- to_inch(cam_file)¶
Convert Gerber or Excellon file units to imperial
Parameters: cam_file : gerber.cam.CamFile subclass
Gerber or Excellon file to convert
Returns: cam_file : gerber.cam.CamFile subclass
A deep copy of the source file with units converted to imperial.
- to_metric(cam_file)¶
Convert Gerber or Excellon file units to metric
Parameters: cam_file : gerber.cam.CamFile subclass
Gerber or Excellon file to convert
Returns: cam_file : gerber.cam.CamFile subclass
A deep copy of the source file with units converted to metric.
- offset(cam_file, x_offset, y_offset)¶
Offset a Cam file by a specified amount in the X and Y directions.
Parameters: cam_file : gerber.cam.CamFile subclass
Gerber or Excellon file to offset
x_offset : float
Amount to offset the file in the X direction
y_offset : float
Amount to offset the file in the Y direction
Returns: cam_file : gerber.cam.CamFile subclass
An offset deep copy of the source file.