Answers Database
1.5i Back Annotation - Ngdanno creates a dangling net in a design.
Record #5545
Product Family: Software
Product Line: FPGA Implementation
Product Part: ngdanno
Product Version: 1.5i
Problem Title:
1.5i Back Annotation - Ngdanno creates a dangling net in a design.
Problem Description:
This problem can be traced back to the ngdbuild models for the LUT1* components. Since NGD ROM prim
itives must have at least 2 inputs, a second input is added during ngdbuild and is never connected.
A simple change to the ngdbuild models in unipro.ngl (add TIEOFF props to the 2nd input on all LUT1
models) seems to solve the problem.
Solution 1:
A fix for this problem is included in the 1.5i Service Pack 1. For details
on this Service Pack see http://www.xilinx.com/techdocs/5514.htm
End of Record #5545 - Last Modified: 02/20/99 19:34 |
