On 15 Oct 98 at 8:36, Dave Roesler wrote:
> (snip snap)
> This leaves the CAM vendor with the responsibility of trying to read
> every flavor and interpretation of RS 274X.  One of the biggest
> issues is polygons. I would venture to guess that most of the
> polygons that VALOR CAM says are illegal would not plot if sent
> directly to the photoplotter.  In this case, the CAM software must
> be robust enough to handle the illegal polygons and make them
> plottable.
... but the CAM SW should do this not silently but should say what is
illegal and give a report what hes to changed.
If the prototype manufacturer "repairs" and plots these files well,
then the customer might think "everything OK" and will fall on his
nose with the same data at the mass production manufacturer. I know
this problem well because I had a similar problem with a half-wrong
Sieb & Meyer drill data output which would run well on the one CAM
software and would produce wrong drill hits on the other CAM
software!
Concerning Compatibility: If you have the RS274X-Specs (they were
ready for download at Gerber Systems, but the URL may have moved
after Barco acquired them) available, you should build manually a
minimal  gerber file which contains only of these gerber elements you
want to check (e.g. only necessary apertures and one single raster
polygon) and then check what comes out with your CAM software. I
assume that a CAM software sold as OEM software from Gerber
Systems directly could be considered as "gold standard" for
correct gerber files.
Regards
Matthias Mansfeld

-----------------------------------------------
Matthias Mansfeld Elektronik
* Printed Circuit Board Design and Assembly
Am Langhoelzl 11, D-85540 Haar, GERMANY
Phone: +49-89-4620 0937, Fax: +49-89-4620 0938
E-Mail: [log in to unmask]
Internet: http://www.mansfeld-elektronik.de

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