The System Generator-generated ISE project incorrectly defaults to XST and when I run "generate" for a compilation target which runs synthesis using Synplify Pro, XST is incorrectly used if my project is targeting a Spartan-3A DSP part.
This problem is due to a known issue with ISE that causes the project file to revert to using XST for Spartan-3A projects. This affects only the ISE 9.2.02 release and will be fixed in future versions.
The tactical patch to resolve this issue can be downloaded at:
1. Install ISE 9.2 sp2 and IP Update #1.
2. Close all Xilinx programs.
3. Download the ZIP file S3ADSP_Synplify_patch.zip.
4. Unzip the file to $XILINX, where $XILINX is the root installation directory of Xilinx ISE 9.2.
5. Click Yes, if asked to overwrite the files.