OpenFPGA/openfpga_flow/openfpga_cell_library/verilog/mult_32x32.v

36 lines
1017 B
Verilog

//-----------------------------------------------------
// Design Name : mult_32x32
// File Name : mult_32x32.v
// Function : A 32-bit multiplier which can operate in fracturable modes:
// 1. four 8-bit multipliers
// 2. two 16-bit multipliers
// 3. one 32-bit multipliers
// Coder : Xifan Tang
//-----------------------------------------------------
module mult_32x32 (
input [0:31] a,
input [0:31] b,
output [0:63] out,
input [0:1] mode);
reg [0:63] out_reg;
always @(mode, a, b) begin
if (2'b01 == mode) begin
out_reg[0:15] <= a[0:7] * b[0:7];
out_reg[16:31] <= a[8:15] * b[8:15];
out_reg[32:47] <= a[16:23] * b[16:23];
out_reg[48:63] <= a[24:31] * b[24:31];
end else if (2'b10 == mode) begin
out_reg[0:31] <= a[0:15] * b[0:15];
out_reg[32:63] <= a[16:31] * b[16:31];
end else begin
out_reg <= a * b;
end
end
assign out = out_reg;
endmodule