7262 - Radiant and Diamond: HDL pin constraints not seen in Spreadsheet View/Device Constraint Editor
Description:
In Lattice Radiant and Diamond, while using the Spreadsheet View/Device Constraint Editor, it is possible to not see the HDL pin constraints reflected in GUI.
Solution:
This may be because the pins mentioned in the lines of code have been optimized by the tool.
See the following warnings:
If the user wants these to appear in Spreadsheet View or Device Constraint Editor, they will need to use the syn_keep attribute to avoid the optimization. Here is an example on CPLD_JTAGEN:
output CPLD_JTAGEN /* synthesis LOC = "C13"*/ /* synthesis syn_keep = 1*/ ,