Answers Database

Mentor/EDIF2XNF: purple LOC properties on PADs are lost, gold propertiesare fine


Record #905

Product Family:  Software

Product Line:  Mentor

Problem Title:
Mentor/EDIF2XNF: purple LOC properties on PADs are lost, gold
propertiesare fine



Problem Description:
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?


Solution 1:

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!



End of Record #905