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12.3 - PlanAhead: Horizontal and Vertical Congestion Metrics are only supported for Virtex-6 FPGA
Receiving the following pop-up error when using "Vertical/Horizontal Routing Congestion per CLB" feature in PlanAhead Metrics window for Spartan-6 FPGA.
This is only supported for Virtex-6 FPGA and not a supported tool with Spartan-6 FPGA.
The PlanAhead User Guide will be updated to outline this.