Why do I see a MAP error, when the SCLR option is not selected, and I try to implement a Multiply Accumulate based Filer Architecture for Spartan-II/-IIE/-3/-3E/-3A or Virtex/-E/-II/-II Pro?
This is due to the fact that the Multiply Accumulate structure that is implemented for the Spartan-II/-IIE/-3/-3E/-3A and Virtex/-E/-II/-II Pro requires an SCRL signal.
The GUI has been updated in the FIR Compiler v3.1 to automatically turn on the SCLR option. This requirement has been removed in the FIR Compiler v3.2 and beyond.
Please see (Xilinx Answer 29138) for a detailed list of LogiCORE FIR Compiler Release Notes and Known Issues.