AR# 905: Mentor/EDIF2XNF: purple LOC properties on PADs are lost, gold properties are fine
Mentor/EDIF2XNF: purple LOC properties on PADs are lost, gold properties are fine
Keywords: edif2xnf, properites missing
Some LOC properties on the pads in my design are not passed to subsequent stages in the design compilation. I've noticed that these LOC properties are displayed as purple text in Design Architect, instead of the normal gold color. What does this mean?
A purple property in Design Architect means that the property is attached to the pin on the PAD symbol, whereas a gold property means that it is attached to the net attached to the pin. Because the PAD symbols in the Mentor libraries are defined as ports, any properties attached to these symbols (i.e., shown in purple) will not be passed to the EDIF file during Men2XNF8, and thus will not be passed to subsequent stages of the compilation.
Usually, LOC properties on Xilinx PAD symbols will transfer to the attached net and will therefore appear gold; however, somethimes the property gets stuck on the PAD pin. Unfortunately, it is not clearly understood why this happens (or even what circumstances cause it to happen), and the only sure workaround is to select the next vertex connected to the offending pin, then add the LOC property to the net vertex. This new property should show up in gold, and thus will be passed to the compilation tools. In any case, beware of purple LOC properties!