Xilinx Virtex-6 Libraries Guide for HDL Designs

Chapter 2: About UnimacrosVerilog Instantiation Template// ADDSUB_MACRO: Variable width & latency - Adder / Subtrator implemented in a DSP48E// Virtex-5, Virtex-6, Spartan-6// Xilinx HDL Libraries Guide, version 11.2ADDSUB_MACRO #(.DEVICE("VIRTEX5"), // Target Device: "VIRTEX5", "VIRTEX6", "SPARTAN6".LATENCY(2), // Desired clock cycle latency, 0-2.WIDTH(48) // Input / output bus width, 1-48) ADDSUB_MACRO_inst (.CARRYOUT(CARRYOUT), // 1-bit carry-out output signal.RESULT(RESULT), // Add/sub result output, width defined by WIDTH parameter.A(A),// Input A bus, width defined by WIDTH parameter.ADD_SUB(ADD_SUB), // 1-bit add/sub input, high selects add, low selects subtract.B(B),// Input B bus, width defined by WIDTH parameter.CARRYIN(CARRYIN), // 1-bit carry-in input.CE(CE),// 1-bit clock enable input.CLK(CLK),// 1-bit clock input.RST(RST)// 1-bit active high synchrnous reset);// End of ADDSUB_MACRO_inst instantiationFor More InformationSee the Virtex-6 FPGA User Documentation (User Guides and Data Sheets).Virtex-6 Libraries Guide for HDL DesignsUG623 (v 11.4) December 2, 2009 www.xilinx.com 59