RS-274X数据格式

The Gerber Format Specification RS-274X or Extended Gerber
Ucamco Former Barco ETs Preface Gerber files are the de facto standard for PCB image data transfer virtually every PCB design system outputs RS-274X (also known as Extended Gerber or X-Data) and every PCB front-end engineering system inputs it. Implementations are thoroughly field-tested and debugged. Its widespread availability allows PCB professionals to exchange image drill and route securely and efficiently The RS-274X format is simple, compact and unequivocal. It is easy to interpret It describes an image with very high precision. It is complete: one single file describes an image. It is portable and easy to debug by its use of printable 7-bit Ascll characters A well-constructed RS-274X file precisely defines the PCB image data and the functions of the different image elements. Unfortunately, poorly constructed or simply erroneous RS-274X files also circulate, sometimes leading to unjustified criticism of the format itself Errors may be due to a misunderstanding of the format. With more than 25 years experience in Cam software we at Ucamco know which areas are most often misunderstood. This revision of the rs-274X specification explains these areas more clearly. Other files are not invalid but poorly constructed. Especially troublesome are painted or stroked pads and copper planes. Poorly constructed files take longer to process, require more manual work and increase the risk of errors. This revision of the RS-274X specification recommends constructions to make rs-274X files safer and more efficient, and hence fabrication more reliable, faster and cheaper A few words must be said about rs-274-d or standard gerber this format was developed to drive Nc machine tools and was used for Gerber vector plotters in the 1960s and 1970s. It is not an image description format. It is amazing that it is still used. It is like using teletype paper tape to transfer text documents. We call on industry experts and professional organizations to discourage the use of the obsolete rs-274-D format Although other data transfer formats have come into the market, they have not displaced RS-274X. The reason is simple. More than 90% of the problems in data transfer are due not to limitations in the rs-274X format but to poor practices and worse, the use of RS-274-D. To quote a PCB manufacturer: If we would only receive proper Rs-274X files, it would be a perfect world The new formats are more complex and less transparent to the user, and new implementations inevitably have bugs. Using the common poor practices in the newer and more complex formats makes matters worse, not better Fabricators have not adopted the new formats. Rs-274x remains the standard The emergence of rs-274X as a standard for image exchange is the result of effort by many individuals who developed outstanding software for Rs-274X files Without their dedication the widespread acceptance of rs-274X could not have been achieved Ucamco thanks these dedicated individuals Karel Tavernier Managing Director Ucamco RS-274X(EXtended Gerber)Format Specification Ucamco Former Barco ETs anuary 2012 Revision h Copyright Ucamco Nv, Gent, Belgium All rights reserved This material, information and instructions for use contained herein are the property of uca The material, information and instructions are provided on an As is basis without warranty of any kind. There are no warranties granted or extended by this document. Furthermore Ucamco does not warrant, guarantee or make any representations regarding the use, or the results of the use of the software or the information contained herein Camco shall not be liable for any direct, indirect, consequential or incidental damages arising out of the use or inability to use the software or the information contained herein The information contained herein is subject to change without prior notice. Revisions may be issued from time to time to advise of such changes and/ or additions No part of this document may be reproduced, stored in a data base or retrieval system, or published, in any form or in any way, electronically, mechanically, by print, photoprint, microfilm or any other means without prior written permission from Ucamco This document supersedes all previous dated versions All product names cited are trademarks or registered trademarks of their respective owners The rs-274X format is Ucamco intellectual property. It cannot be altered or extended in any way without prior written approval from Ucamco Correspondence regarding this publication can be sent to Ucamco Nv Bijenstraat 19 B-9051 Gent Bels For more information Durwebsitehttp://www.ucamco.com E-mail:info(aucamco.com RS-274X(EXtended Gerber) Format Specification Ucamco Former Barco ETs About ucamco Ucamco(former Barco ETS)is a market leader in PCB CAM software and laser photoplotting systems We have more than 25 years continuous experience developing and supporting leading-edge front-end tooling solutions for the global PCB industry. We help fabricators world-wide raise yields, increase factory productivity, and cut enterprise risks and costs Today we have more than 1000 laser photoplotter and 5000 CAM systems installed around the world with local support in every major market. Our customers include the leading PCB fabricators across the global spectrum. Many of them have been with us for more than 20 years Key to this success has been our uncompromising pursuit of engineering excellence in all our products. For 25 years our product goals have been best-in-class performance, long-term reliability, and continuous development to keep each user at the cutting-edge of his chosen technolog RS-274X(EXtended Gerber) Format Specification Ucamco Former Barco ETs Table of contents Preface Tab| e of contents∴ 1 Introduction 1 who should use this specification? 1.2 About This document 1.3 History of the Gerber Format 2 synta 10 2.1 Character Set 2.2 Data blocks… ·, 10 2. 3 Data types 2 4 Coordinate data 2.5 Function codes 2.6 Parameters 3 mage Generation.,,…,,……,……………13 3.1 Information l ······+·::4··········+ 3.2 Generating the Information Layer Image 4 Parameters…… 14 4.1 AD-Aperture Definition 4.1.1 Standard apertures 垂··“垂 4.1.2 Special apertures 4.1.3 tax rules 41. 4 Data block format 15 4. 1. 5 Aperture Definition with Standard apertures 4.1.6 Examples 17 4.2 AM- Aperture Macro 4.2.1 Contents ………………………18 4.2.2 Syntax rules 4.2. 3 Data block format 4.2. 4 Primitives 20 4.2.5 Examples… RS-274X(EXtended Gerber) Format Specification Ucamco Former Barco ETs 4.2.6 SM-Symbol mirror 25 4.3 Directive parameters 26 4.3. 1 AS- Axis Select 26 4.3.2 FS-Format Specification 27 4.3. 3 MI-Mirror Image ∴29 43. 4 Mo Mod ,30 4.3.5OF- Offset… 31 4.3.6 SF-Scale factor 4.4 Image parameters… 33 4.4.lIP- Image Polarity……… 3 44.2 iR- Image Rotation……… …34 4.5 Layer-specific parameters 4.5.1 KO-Knock Out 4.52N- Layer Name…… 4.5.3 SR-Step and Repeat...... ∴.39 5 Function Codes 5.1 Overview 40 5.2 Linear Interpolation(GOl(Gl) 42 5.2. 1 Data block format.……… …942 5.3 Circular Interpolation(G02(G2), G03(G3), G74, G75) 43 5.3. 1 Single Quadrant Mode.... 44 5.3.2 Multi Quadrant mode 45 5.3.3 Example 46 5.4 Apertures allowed for drawing.... …47 5.4.1 Circle aperture 47 5.4.2 Rectangle or Square Aperture 47 5.5 Outline Fill(G36, G37) +++,·, 48 5.5.1上 xample I: Simple outline…… 5.5.2 Example2: Cut in……… 49 5.5.3 Example 3: More complex cut-in 6 RS-274X Best Practices 1,重面目 53 7 Common Syntax Errors…,… 55 8 Glossary… 9 Sample Files,,…,,, 58 9. 1. 1 Example 58 9. 1.2 Example RS-274X(EXtended Gerber) Format Specification Ucamco Former Barco ETs 1 Introduction 1.1 Who should use this specification? This specification is intended for 口 PCB designers preparing RS274× <files o PCB fabricators creating or using RS-274X files a Developers of software applications using rs-274X files 1.2 About this document The following conventions are used in this document Note Provides essential extra information Tip: Provides useful extra information Example: Contains examples of file syntax, commands, settings etc △ Warning Contains an important warning 1.3 History of the Gerber Format Gerber Format derives its name from the former gerber Systems corporation a leading supplier of photoplotter Originally, Gerber used a subset of the Standard Rs-274-D format as input format for its photoplotter. This subset became known as Standard Gerber. It is not an image description format, but a format to drive mechanical machine tools, which photo- plotters originally were, where apertures shapes where physical apertures in a so called aperture wheel and it actually became a family of formats. The Gerber formats developed into i es In subsequent years, Gerber extended the input format for its range of Pcb devi capable image description format. In 1998 the formats were pulled together and standardized by the publication of the first version of this document. Since then, it has become the de-facto standard for pcb image data RS-274X (EXtended Gerber)Format Specification 9 Ucamco Former Barco ETs 2 Syntax 2.1 Character Set An RS-274x file is expressed in printable 7-bit ASCll characters only 22 Data blocks The file is composed of data blocks. each data block ends with the mandatory end-of- block character asterisk " Each data block may contain one or more parameters codes or coordinates For example XOYOD02 x50000Y0Do1* For readability it is recommended to a Begin independent data blocks on a new line. Peep each data block one line 2.3 Data Types There are the following data types 1 Coordinate Data 2 Function Codes 3 Parameters 2.4 Coordinate Data Coordinate data to define points in the plane. (They were called addresses in the obsolete RS-274-D terminology ) Coordinate data can be o X,Y data to define the x, r coordinates of a point o j data to define an offset in the x. y direction The Fs Parameter (Format Specification) specifies how the digits must be interpreted Right handed orthonormal coordinates are used Coordinates are modal. if an x is omitted the last x coordinate is used if the first x in the current layer is omitted, there is no last X coordinate and zero is used as default Similar for y coordinates Note: Gerber readers sometimes handle the zero default wrongly. For clarity and robustness it is recommend not to count on the zero default, but always to specify the first coordinate explicitly, also if it is zero Offsets are not modal, if i or j is omitted the default zero is used RS-274X (EXtended Gerber)Format Specification 10