// Copyright 2007 Altera Corporation. All rights reserved. // Altera products are protected under numerous U.S. and foreign patents, // maskwork rights, copyrights and other intellectual property laws. // // This reference design file, and your use thereof, is subject to and governed // by the terms and conditions of the applicable Altera Reference Design // License Agreement (either as signed by you or found at www.altera.com). By // using this reference design file, you indicate your acceptance of such terms // and conditions between you and Altera Corporation. In the event that you do // not agree with such terms and conditions, you may not use the reference // design file and please promptly destroy any copies you have made. // // This reference design file is being provided on an "as-is" basis and as an // accommodation and therefore all warranties, representations or guarantees of // any kind (whether express, implied or statutory) including, without // limitation, warranties of merchantability, non-infringement, or fitness for // a particular purpose, are specifically disclaimed. By making this reference // design file available, Altera expressly does not recommend, suggest or // require that this reference design file be used in combination with any // other product not provided by Altera. ///////////////////////////////////////////////////////////////////////////// module mask_32 (in,mask); input [4:0] in; output [31:0] mask; reg [31:0] mask; parameter FROM_MSB = 1'b1; parameter DIAG_ONES = 1'b1; generate if (!FROM_MSB && !DIAG_ONES) begin always @(in) begin case (in) 5'd0: mask=32'b00000000000000000000000000000000; 5'd1: mask=32'b00000000000000000000000000000001; 5'd2: mask=32'b00000000000000000000000000000011; 5'd3: mask=32'b00000000000000000000000000000111; 5'd4: mask=32'b00000000000000000000000000001111; 5'd5: mask=32'b00000000000000000000000000011111; 5'd6: mask=32'b00000000000000000000000000111111; 5'd7: mask=32'b00000000000000000000000001111111; 5'd8: mask=32'b00000000000000000000000011111111; 5'd9: mask=32'b00000000000000000000000111111111; 5'd10: mask=32'b00000000000000000000001111111111; 5'd11: mask=32'b00000000000000000000011111111111; 5'd12: mask=32'b00000000000000000000111111111111; 5'd13: mask=32'b00000000000000000001111111111111; 5'd14: mask=32'b00000000000000000011111111111111; 5'd15: mask=32'b00000000000000000111111111111111; 5'd16: mask=32'b00000000000000001111111111111111; 5'd17: mask=32'b00000000000000011111111111111111; 5'd18: mask=32'b00000000000000111111111111111111; 5'd19: mask=32'b00000000000001111111111111111111; 5'd20: mask=32'b00000000000011111111111111111111; 5'd21: mask=32'b00000000000111111111111111111111; 5'd22: mask=32'b00000000001111111111111111111111; 5'd23: mask=32'b00000000011111111111111111111111; 5'd24: mask=32'b00000000111111111111111111111111; 5'd25: mask=32'b00000001111111111111111111111111; 5'd26: mask=32'b00000011111111111111111111111111; 5'd27: mask=32'b00000111111111111111111111111111; 5'd28: mask=32'b00001111111111111111111111111111; 5'd29: mask=32'b00011111111111111111111111111111; 5'd30: mask=32'b00111111111111111111111111111111; 5'd31: mask=32'b01111111111111111111111111111111; default: mask=0; endcase end end else if ( FROM_MSB && !DIAG_ONES) begin always @(in) begin case (in) 5'd0: mask=32'b00000000000000000000000000000000; 5'd1: mask=32'b10000000000000000000000000000000; 5'd2: mask=32'b11000000000000000000000000000000; 5'd3: mask=32'b11100000000000000000000000000000; 5'd4: mask=32'b11110000000000000000000000000000; 5'd5: mask=32'b11111000000000000000000000000000; 5'd6: mask=32'b11111100000000000000000000000000; 5'd7: mask=32'b11111110000000000000000000000000; 5'd8: mask=32'b11111111000000000000000000000000; 5'd9: mask=32'b11111111100000000000000000000000; 5'd10: mask=32'b11111111110000000000000000000000; 5'd11: mask=32'b11111111111000000000000000000000; 5'd12: mask=32'b11111111111100000000000000000000; 5'd13: mask=32'b11111111111110000000000000000000; 5'd14: mask=32'b11111111111111000000000000000000; 5'd15: mask=32'b11111111111111100000000000000000; 5'd16: mask=32'b11111111111111110000000000000000; 5'd17: mask=32'b11111111111111111000000000000000; 5'd18: mask=32'b11111111111111111100000000000000; 5'd19: mask=32'b11111111111111111110000000000000; 5'd20: mask=32'b11111111111111111111000000000000; 5'd21: mask=32'b11111111111111111111100000000000; 5'd22: mask=32'b11111111111111111111110000000000; 5'd23: mask=32'b11111111111111111111111000000000; 5'd24: mask=32'b11111111111111111111111100000000; 5'd25: mask=32'b11111111111111111111111110000000; 5'd26: mask=32'b11111111111111111111111111000000; 5'd27: mask=32'b11111111111111111111111111100000; 5'd28: mask=32'b11111111111111111111111111110000; 5'd29: mask=32'b11111111111111111111111111111000; 5'd30: mask=32'b11111111111111111111111111111100; 5'd31: mask=32'b11111111111111111111111111111110; default: mask=0; endcase end end else if (!FROM_MSB && DIAG_ONES) begin always @(in) begin case (in) 5'd0: mask=32'b00000000000000000000000000000001; 5'd1: mask=32'b00000000000000000000000000000011; 5'd2: mask=32'b00000000000000000000000000000111; 5'd3: mask=32'b00000000000000000000000000001111; 5'd4: mask=32'b00000000000000000000000000011111; 5'd5: mask=32'b00000000000000000000000000111111; 5'd6: mask=32'b00000000000000000000000001111111; 5'd7: mask=32'b00000000000000000000000011111111; 5'd8: mask=32'b00000000000000000000000111111111; 5'd9: mask=32'b00000000000000000000001111111111; 5'd10: mask=32'b00000000000000000000011111111111; 5'd11: mask=32'b00000000000000000000111111111111; 5'd12: mask=32'b00000000000000000001111111111111; 5'd13: mask=32'b00000000000000000011111111111111; 5'd14: mask=32'b00000000000000000111111111111111; 5'd15: mask=32'b00000000000000001111111111111111; 5'd16: mask=32'b00000000000000011111111111111111; 5'd17: mask=32'b00000000000000111111111111111111; 5'd18: mask=32'b00000000000001111111111111111111; 5'd19: mask=32'b00000000000011111111111111111111; 5'd20: mask=32'b00000000000111111111111111111111; 5'd21: mask=32'b00000000001111111111111111111111; 5'd22: mask=32'b00000000011111111111111111111111; 5'd23: mask=32'b00000000111111111111111111111111; 5'd24: mask=32'b00000001111111111111111111111111; 5'd25: mask=32'b00000011111111111111111111111111; 5'd26: mask=32'b00000111111111111111111111111111; 5'd27: mask=32'b00001111111111111111111111111111; 5'd28: mask=32'b00011111111111111111111111111111; 5'd29: mask=32'b00111111111111111111111111111111; 5'd30: mask=32'b01111111111111111111111111111111; 5'd31: mask=32'b11111111111111111111111111111111; default: mask=0; endcase end end else if ( FROM_MSB && DIAG_ONES) begin always @(in) begin case (in) 5'd0: mask=32'b10000000000000000000000000000000; 5'd1: mask=32'b11000000000000000000000000000000; 5'd2: mask=32'b11100000000000000000000000000000; 5'd3: mask=32'b11110000000000000000000000000000; 5'd4: mask=32'b11111000000000000000000000000000; 5'd5: mask=32'b11111100000000000000000000000000; 5'd6: mask=32'b11111110000000000000000000000000; 5'd7: mask=32'b11111111000000000000000000000000; 5'd8: mask=32'b11111111100000000000000000000000; 5'd9: mask=32'b11111111110000000000000000000000; 5'd10: mask=32'b11111111111000000000000000000000; 5'd11: mask=32'b11111111111100000000000000000000; 5'd12: mask=32'b11111111111110000000000000000000; 5'd13: mask=32'b11111111111111000000000000000000; 5'd14: mask=32'b11111111111111100000000000000000; 5'd15: mask=32'b11111111111111110000000000000000; 5'd16: mask=32'b11111111111111111000000000000000; 5'd17: mask=32'b11111111111111111100000000000000; 5'd18: mask=32'b11111111111111111110000000000000; 5'd19: mask=32'b11111111111111111111000000000000; 5'd20: mask=32'b11111111111111111111100000000000; 5'd21: mask=32'b11111111111111111111110000000000; 5'd22: mask=32'b11111111111111111111111000000000; 5'd23: mask=32'b11111111111111111111111100000000; 5'd24: mask=32'b11111111111111111111111110000000; 5'd25: mask=32'b11111111111111111111111111000000; 5'd26: mask=32'b11111111111111111111111111100000; 5'd27: mask=32'b11111111111111111111111111110000; 5'd28: mask=32'b11111111111111111111111111111000; 5'd29: mask=32'b11111111111111111111111111111100; 5'd30: mask=32'b11111111111111111111111111111110; 5'd31: mask=32'b11111111111111111111111111111111; default: mask=0; endcase end end endgenerate endmodule