> I do not know what most assembly houses require. I took a quick look > at IPC-2581 "Generic Requirements for Printed Board Assembly" (March > 2004, pages 11-12). The convention in IPC-2581 states both parts > should have angle=0 and the part on the bottom should have a mirror > attribute. Angles are positive for counter-clockwise rotation. > Was the xy-data done for a specific machine or specification?
The machines that I have worked with (Samsung) were only interested in a rotation - I've never seen any references to a mirror attribute. A P&P machine can only rotate the components, so they just need the correct rotation for when the side being populated is facing upwards. What might vary a bit is how the operators flip a board - if they flip it in the top/bottom direction the relative rotation is 180º, if they flip it left/right then the relative rotation would be 0º (but they would just correct this on the machine if it differed). _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
