On 1 Nov 96 at 8:18, dmyers wrote: > We have seen problems with the RS274-X format. It seems that > our customers supply all RS274-x data with no flashed > apertures. Instead the use hundreds of macros. > > The first thing that happens is you read the data in through > your design input software. (IGI, Valor, Orbotech, whatever) and > the data is interpretted very quickly with little human > intervention. So far so good. > > However, when you decide to check your work, run analysis or > DRCs, you find that you have no idea what diameter your > pads are. If you need to extract a netlist for Test issues, > then your really Whew. Macros instead of flashed circles? I would be interested to know which CAD package does that. I use the macros extensively on my surface mount pads to customize and to round off the sharp corners on rectangular pads. I am very pleased with the result in the copper, soldermask, and paste stencil. If I knew my board vendor was making extensive edits to my gerber output, I would fix the problem and generate correct files. Do your customers know you do this? Extensive edits defeat the purpose of RS-274-X, of course. The netlist problem is a big one. perhaps the software vendors can be persuaded to implement EDIF. I don't hold out much hope for a groundswell of support for IPC-D-356. > stumped. If your CAM operators need to make any edits, for > instance change an .062" diameter pad to .064" for etch > compensation or meeting annular ring requirements, then you > will be spending a very long time making these edits, during > which, you will probably make an error. And creating a > soldermask is impossible. > > We have finally come to the conclusion that it is just too > difficult to deal with this format as it is received today. > When we do receive it, we have our design input operators spend > the day converting all of the "macros" into flashes. We are > then left with the big task of comparing the original data to > the editted data in order to verify that the human intervention > (at this very critical stage) did not cause an error. > > Hope this helps. --- Ross LaGue < [log in to unmask] > Dayton, Ohio *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************