Gerber RS274X

Gerber File Formats RS-274D RS-274X.

Gerber plot files traditionally RS-274D format are a vector plotting/NC machine control language. We preferred leading zero, 2-3, imperial format. In that format a position of 0.1" would be written as 100. Without the suppression the same position would be written as 00100. The language doesn't support the decimal point which is why it requires the extra 2-3 or 2-4 qualification. The first number represents the number of integer digits, and the second represents the number of decimal digits. In 2-4 format without the zero suppression our 0.1" would read 001000. To further confuse things we can also have trailing zero suppression, in this case our 0.1" would read 001 in both 2-3 and 2-4 format. A file plotted to RS-274D format also requires an aperture table to qualify it where as the RS-274X has the aperture sizes imbedded in its header section. For anyone who is interested I have included a brief summary of the command codes below. Detailed PDF files can be downloaded from the Ucamco website which contain the more recent specification of the Gerber format. Ucamco-Downloads

Basic Photo Plotter Commands:-
D01 --Turn light on to draw, Used for drawing lines. D02--Turn Light off, D03--Flash, Used for drawing pads, D10--Onwards, Select aperture. To flash a pad at 0.51.0" the command would be X00500Y01000D03

If in doubt about the formats:-
Don't even look at any of the output settings on your CAD package, just create the plot files and send them over to us. The chances are we can easily determine the format simply by looking at your file. If you are worried we are always happy to fax a preview of the photo plots through before we commence production of the boards.
Gerber Viewer Links
Cam350	Camtastic
GC-Prevue	Viewmate


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