i ve written verilog code for crc32 with 32 bit data width as follows
// CRC module for data[31:0] , 
crc[31:0]=1+x^1+x^2+x^4+x^5+x^7+x^8+x^10+x^11+x^12+x^16+x^22+x^23+x^26+x 
^32;
//---------------------------------------------------------------------- 
-------
module crc(
input [31:0] data_in,
input crc_en,
output [31:0] crc_out,
input rst,
input clk);

reg [31:0] lfsr_q,lfsr_c;

assign crc_out = lfsr_q;

always @(*) begin
lfsr_c[0] = lfsr_q[0] ^ lfsr_q[6] ^ lfsr_q[9] ^ lfsr_q[10] ^ lfsr_q[12] 
^ lfsr_q[16] ^ lfsr_q[24] ^ lfsr_q[25] ^ lfsr_q[26] ^ lfsr_q[28] ^ 
lfsr_q[29] ^ lfsr_q[30] ^ lfsr_q[31] ^ data_in[0] ^ data_in[6] ^ 
data_in[9] ^ data_in[10] ^ data_in[12] ^ data_in[16] ^ data_in[24] ^ 
data_in[25] ^ data_in[26] ^ data_in[28] ^ data_in[29] ^ data_in[30] ^ 
data_in[31];
lfsr_c[1] = lfsr_q[0] ^ lfsr_q[1] ^ lfsr_q[6] ^ lfsr_q[7] ^ lfsr_q[9] ^ 
lfsr_q[11] ^ lfsr_q[12] ^ lfsr_q[13] ^ lfsr_q[16] ^ lfsr_q[17] ^ 
lfsr_q[24] ^ lfsr_q[27] ^ lfsr_q[28] ^ data_in[0] ^ data_in[1] ^ 
data_in[6] ^ data_in[7] ^ data_in[9] ^ data_in[11] ^ data_in[12] ^ 
data_in[13] ^ data_in[16] ^ data_in[17] ^ data_in[24] ^ data_in[27] ^ 
data_in[28];
lfsr_c[2] = lfsr_q[0] ^ lfsr_q[1] ^ lfsr_q[2] ^ lfsr_q[6] ^ lfsr_q[7] ^ 
lfsr_q[8] ^ lfsr_q[9] ^ lfsr_q[13] ^ lfsr_q[14] ^ lfsr_q[16] ^ 
lfsr_q[17] ^ lfsr_q[18] ^ lfsr_q[24] ^ lfsr_q[26] ^ lfsr_q[30] ^ 
lfsr_q[31] ^ data_in[0] ^ data_in[1] ^ data_in[2] ^ data_in[6] ^ 
data_in[7] ^ data_in[8] ^ data_in[9] ^ data_in[13] ^ data_in[14] ^ 
data_in[16] ^ data_in[17] ^ data_in[18] ^ data_in[24] ^ data_in[26] ^ 
data_in[30] ^ data_in[31];
lfsr_c[3] = lfsr_q[1] ^ lfsr_q[2] ^ lfsr_q[3] ^ lfsr_q[7] ^ lfsr_q[8] ^ 
lfsr_q[9] ^ lfsr_q[10] ^ lfsr_q[14] ^ lfsr_q[15] ^ lfsr_q[17] ^ 
lfsr_q[18] ^ lfsr_q[19] ^ lfsr_q[25] ^ lfsr_q[27] ^ lfsr_q[31] ^ 
data_in[1] ^ data_in[2] ^ data_in[3] ^ data_in[7] ^ data_in[8] ^ 
data_in[9] ^ data_in[10] ^ data_in[14] ^ data_in[15] ^ data_in[17] ^ 
data_in[18] ^ data_in[19] ^ data_in[25] ^ data_in[27] ^ data_in[31];
lfsr_c[4] = lfsr_q[0] ^ lfsr_q[2] ^ lfsr_q[3] ^ lfsr_q[4] ^ lfsr_q[6] ^ 
lfsr_q[8] ^ lfsr_q[11] ^ lfsr_q[12] ^ lfsr_q[15] ^ lfsr_q[18] ^ 
lfsr_q[19] ^ lfsr_q[20] ^ lfsr_q[24] ^ lfsr_q[25] ^ lfsr_q[29] ^ 
lfsr_q[30] ^ lfsr_q[31] ^ data_in[0] ^ data_in[2] ^ data_in[3] ^ 
data_in[4] ^ data_in[6] ^ data_in[8] ^ data_in[11] ^ data_in[12] ^ 
data_in[15] ^ data_in[18] ^ data_in[19] ^ data_in[20] ^ data_in[24] ^ 
data_in[25] ^ data_in[29] ^ data_in[30] ^ data_in[31];
lfsr_c[5] = lfsr_q[0] ^ lfsr_q[1] ^ lfsr_q[3] ^ lfsr_q[4] ^ lfsr_q[5] ^ 
lfsr_q[6] ^ lfsr_q[7] ^ lfsr_q[10] ^ lfsr_q[13] ^ lfsr_q[19] ^ 
lfsr_q[20] ^ lfsr_q[21] ^ lfsr_q[24] ^ lfsr_q[28] ^ lfsr_q[29] ^ 
data_in[0] ^ data_in[1] ^ data_in[3] ^ data_in[4] ^ data_in[5] ^ 
data_in[6] ^ data_in[7] ^ data_in[10] ^ data_in[13] ^ data_in[19] ^ 
data_in[20] ^ data_in[21] ^ data_in[24] ^ data_in[28] ^ data_in[29];
lfsr_c[6] = lfsr_q[1] ^ lfsr_q[2] ^ lfsr_q[4] ^ lfsr_q[5] ^ lfsr_q[6] ^ 
lfsr_q[7] ^ lfsr_q[8] ^ lfsr_q[11] ^ lfsr_q[14] ^ lfsr_q[20] ^ 
lfsr_q[21] ^ lfsr_q[22] ^ lfsr_q[25] ^ lfsr_q[29] ^ lfsr_q[30] ^ 
data_in[1] ^ data_in[2] ^ data_in[4] ^ data_in[5] ^ data_in[6] ^ 
data_in[7] ^ data_in[8] ^ data_in[11] ^ data_in[14] ^ data_in[20] ^ 
data_in[21] ^ data_in[22] ^ data_in[25] ^ data_in[29] ^ data_in[30];
lfsr_c[7] = lfsr_q[0] ^ lfsr_q[2] ^ lfsr_q[3] ^ lfsr_q[5] ^ lfsr_q[7] ^ 
lfsr_q[8] ^ lfsr_q[10] ^ lfsr_q[15] ^ lfsr_q[16] ^ lfsr_q[21] ^ 
lfsr_q[22] ^ lfsr_q[23] ^ lfsr_q[24] ^ lfsr_q[25] ^ lfsr_q[28] ^ 
lfsr_q[29] ^ data_in[0] ^ data_in[2] ^ data_in[3] ^ data_in[5] ^ 
data_in[7] ^ data_in[8] ^ data_in[10] ^ data_in[15] ^ data_in[16] ^ 
data_in[21] ^ data_in[22] ^ data_in[23] ^ data_in[24] ^ data_in[25] ^ 
data_in[28] ^ data_in[29];
lfsr_c[8] = lfsr_q[0] ^ lfsr_q[1] ^ lfsr_q[3] ^ lfsr_q[4] ^ lfsr_q[8] ^ 
lfsr_q[10] ^ lfsr_q[11] ^ lfsr_q[12] ^ lfsr_q[17] ^ lfsr_q[22] ^ 
lfsr_q[23] ^ lfsr_q[28] ^ lfsr_q[31] ^ data_in[0] ^ data_in[1] ^ 
data_in[3] ^ data_in[4] ^ data_in[8] ^ data_in[10] ^ data_in[11] ^ 
data_in[12] ^ data_in[17] ^ data_in[22] ^ data_in[23] ^ data_in[28] ^ 
data_in[31];
lfsr_c[9] = lfsr_q[1] ^ lfsr_q[2] ^ lfsr_q[4] ^ lfsr_q[5] ^ lfsr_q[9] ^ 
lfsr_q[11] ^ lfsr_q[12] ^ lfsr_q[13] ^ lfsr_q[18] ^ lfsr_q[23] ^ 
lfsr_q[24] ^ lfsr_q[29] ^ data_in[1] ^ data_in[2] ^ data_in[4] ^ 
data_in[5] ^ data_in[9] ^ data_in[11] ^ data_in[12] ^ data_in[13] ^ 
data_in[18] ^ data_in[23] ^ data_in[24] ^ data_in[29];
lfsr_c[10] = lfsr_q[0] ^ lfsr_q[2] ^ lfsr_q[3] ^ lfsr_q[5] ^ lfsr_q[9] ^ 
lfsr_q[13] ^ lfsr_q[14] ^ lfsr_q[16] ^ lfsr_q[19] ^ lfsr_q[26] ^ 
lfsr_q[28] ^ lfsr_q[29] ^ lfsr_q[31] ^ data_in[0] ^ data_in[2] ^ 
data_in[3] ^ data_in[5] ^ data_in[9] ^ data_in[13] ^ data_in[14] ^ 
data_in[16] ^ data_in[19] ^ data_in[26] ^ data_in[28] ^ data_in[29] ^ 
data_in[31];
lfsr_c[11] = lfsr_q[0] ^ lfsr_q[1] ^ lfsr_q[3] ^ lfsr_q[4] ^ lfsr_q[9] ^ 
lfsr_q[12] ^ lfsr_q[14] ^ lfsr_q[15] ^ lfsr_q[16] ^ lfsr_q[17] ^ 
lfsr_q[20] ^ lfsr_q[24] ^ lfsr_q[25] ^ lfsr_q[26] ^ lfsr_q[27] ^ 
lfsr_q[28] ^ lfsr_q[31] ^ data_in[0] ^ data_in[1] ^ data_in[3] ^ 
data_in[4] ^ data_in[9] ^ data_in[12] ^ data_in[14] ^ data_in[15] ^ 
data_in[16] ^ data_in[17] ^ data_in[20] ^ data_in[24] ^ data_in[25] ^ 
data_in[26] ^ data_in[27] ^ data_in[28] ^ data_in[31];
lfsr_c[12] = lfsr_q[0] ^ lfsr_q[1] ^ lfsr_q[2] ^ lfsr_q[4] ^ lfsr_q[5] ^ 
lfsr_q[6] ^ lfsr_q[9] ^ lfsr_q[12] ^ lfsr_q[13] ^ lfsr_q[15] ^ 
lfsr_q[17] ^ lfsr_q[18] ^ lfsr_q[21] ^ lfsr_q[24] ^ lfsr_q[27] ^ 
lfsr_q[30] ^ lfsr_q[31] ^ data_in[0] ^ data_in[1] ^ data_in[2] ^ 
data_in[4] ^ data_in[5] ^ data_in[6] ^ data_in[9] ^ data_in[12] ^ 
data_in[13] ^ data_in[15] ^ data_in[17] ^ data_in[18] ^ data_in[21] ^ 
data_in[24] ^ data_in[27] ^ data_in[30] ^ data_in[31];
lfsr_c[13] = lfsr_q[1] ^ lfsr_q[2] ^ lfsr_q[3] ^ lfsr_q[5] ^ lfsr_q[6] ^ 
lfsr_q[7] ^ lfsr_q[10] ^ lfsr_q[13] ^ lfsr_q[14] ^ lfsr_q[16] ^ 
lfsr_q[18] ^ lfsr_q[19] ^ lfsr_q[22] ^ lfsr_q[25] ^ lfsr_q[28] ^ 
lfsr_q[31] ^ data_in[1] ^ data_in[2] ^ data_in[3] ^ data_in[5] ^ 
data_in[6] ^ data_in[7] ^ data_in[10] ^ data_in[13] ^ data_in[14] ^ 
data_in[16] ^ data_in[18] ^ data_in[19] ^ data_in[22] ^ data_in[25] ^ 
data_in[28] ^ data_in[31];
lfsr_c[14] = lfsr_q[2] ^ lfsr_q[3] ^ lfsr_q[4] ^ lfsr_q[6] ^ lfsr_q[7] ^ 
lfsr_q[8] ^ lfsr_q[11] ^ lfsr_q[14] ^ lfsr_q[15] ^ lfsr_q[17] ^ 
lfsr_q[19] ^ lfsr_q[20] ^ lfsr_q[23] ^ lfsr_q[26] ^ lfsr_q[29] ^ 
data_in[2] ^ data_in[3] ^ data_in[4] ^ data_in[6] ^ data_in[7] ^ 
data_in[8] ^ data_in[11] ^ data_in[14] ^ data_in[15] ^ data_in[17] ^ 
data_in[19] ^ data_in[20] ^ data_in[23] ^ data_in[26] ^ data_in[29];
lfsr_c[15] = lfsr_q[3] ^ lfsr_q[4] ^ lfsr_q[5] ^ lfsr_q[7] ^ lfsr_q[8] ^ 
lfsr_q[9] ^ lfsr_q[12] ^ lfsr_q[15] ^ lfsr_q[16] ^ lfsr_q[18] ^ 
lfsr_q[20] ^ lfsr_q[21] ^ lfsr_q[24] ^ lfsr_q[27] ^ lfsr_q[30] ^ 
data_in[3] ^ data_in[4] ^ data_in[5] ^ data_in[7] ^ data_in[8] ^ 
data_in[9] ^ data_in[12] ^ data_in[15] ^ data_in[16] ^ data_in[18] ^ 
data_in[20] ^ data_in[21] ^ data_in[24] ^ data_in[27] ^ data_in[30];
lfsr_c[16] = lfsr_q[0] ^ lfsr_q[4] ^ lfsr_q[5] ^ lfsr_q[8] ^ lfsr_q[12] 
^ lfsr_q[13] ^ lfsr_q[17] ^ lfsr_q[19] ^ lfsr_q[21] ^ lfsr_q[22] ^ 
lfsr_q[24] ^ lfsr_q[26] ^ lfsr_q[29] ^ lfsr_q[30] ^ data_in[0] ^ 
data_in[4] ^ data_in[5] ^ data_in[8] ^ data_in[12] ^ data_in[13] ^ 
data_in[17] ^ data_in[19] ^ data_in[21] ^ data_in[22] ^ data_in[24] ^ 
data_in[26] ^ data_in[29] ^ data_in[30];
lfsr_c[17] = lfsr_q[1] ^ lfsr_q[5] ^ lfsr_q[6] ^ lfsr_q[9] ^ lfsr_q[13] 
^ lfsr_q[14] ^ lfsr_q[18] ^ lfsr_q[20] ^ lfsr_q[22] ^ lfsr_q[23] ^ 
lfsr_q[25] ^ lfsr_q[27] ^ lfsr_q[30] ^ lfsr_q[31] ^ data_in[1] ^ 
data_in[5] ^ data_in[6] ^ data_in[9] ^ data_in[13] ^ data_in[14] ^ 
data_in[18] ^ data_in[20] ^ data_in[22] ^ data_in[23] ^ data_in[25] ^ 
data_in[27] ^ data_in[30] ^ data_in[31];
lfsr_c[18] = lfsr_q[2] ^ lfsr_q[6] ^ lfsr_q[7] ^ lfsr_q[10] ^ lfsr_q[14] 
^ lfsr_q[15] ^ lfsr_q[19] ^ lfsr_q[21] ^ lfsr_q[23] ^ lfsr_q[24] ^ 
lfsr_q[26] ^ lfsr_q[28] ^ lfsr_q[31] ^ data_in[2] ^ data_in[6] ^ 
data_in[7] ^ data_in[10] ^ data_in[14] ^ data_in[15] ^ data_in[19] ^ 
data_in[21] ^ data_in[23] ^ data_in[24] ^ data_in[26] ^ data_in[28] ^ 
data_in[31];
lfsr_c[19] = lfsr_q[3] ^ lfsr_q[7] ^ lfsr_q[8] ^ lfsr_q[11] ^ lfsr_q[15] 
^ lfsr_q[16] ^ lfsr_q[20] ^ lfsr_q[22] ^ lfsr_q[24] ^ lfsr_q[25] ^ 
lfsr_q[27] ^ lfsr_q[29] ^ data_in[3] ^ data_in[7] ^ data_in[8] ^ 
data_in[11] ^ data_in[15] ^ data_in[16] ^ data_in[20] ^ data_in[22] ^ 
data_in[24] ^ data_in[25] ^ data_in[27] ^ data_in[29];
lfsr_c[20] = lfsr_q[4] ^ lfsr_q[8] ^ lfsr_q[9] ^ lfsr_q[12] ^ lfsr_q[16] 
^ lfsr_q[17] ^ lfsr_q[21] ^ lfsr_q[23] ^ lfsr_q[25] ^ lfsr_q[26] ^ 
lfsr_q[28] ^ lfsr_q[30] ^ data_in[4] ^ data_in[8] ^ data_in[9] ^ 
data_in[12] ^ data_in[16] ^ data_in[17] ^ data_in[21] ^ data_in[23] ^ 
data_in[25] ^ data_in[26] ^ data_in[28] ^ data_in[30];
lfsr_c[21] = lfsr_q[5] ^ lfsr_q[9] ^ lfsr_q[10] ^ lfsr_q[13] ^ 
lfsr_q[17] ^ lfsr_q[18] ^ lfsr_q[22] ^ lfsr_q[24] ^ lfsr_q[26] ^ 
lfsr_q[27] ^ lfsr_q[29] ^ lfsr_q[31] ^ data_in[5] ^ data_in[9] ^ 
data_in[10] ^ data_in[13] ^ data_in[17] ^ data_in[18] ^ data_in[22] ^ 
data_in[24] ^ data_in[26] ^ data_in[27] ^ data_in[29] ^ data_in[31];
lfsr_c[22] = lfsr_q[0] ^ lfsr_q[9] ^ lfsr_q[11] ^ lfsr_q[12] ^ 
lfsr_q[14] ^ lfsr_q[16] ^ lfsr_q[18] ^ lfsr_q[19] ^ lfsr_q[23] ^ 
lfsr_q[24] ^ lfsr_q[26] ^ lfsr_q[27] ^ lfsr_q[29] ^ lfsr_q[31] ^ 
data_in[0] ^ data_in[9] ^ data_in[11] ^ data_in[12] ^ data_in[14] ^ 
data_in[16] ^ data_in[18] ^ data_in[19] ^ data_in[23] ^ data_in[24] ^ 
data_in[26] ^ data_in[27] ^ data_in[29] ^ data_in[31];
lfsr_c[23] = lfsr_q[0] ^ lfsr_q[1] ^ lfsr_q[6] ^ lfsr_q[9] ^ lfsr_q[13] 
^ lfsr_q[15] ^ lfsr_q[16] ^ lfsr_q[17] ^ lfsr_q[19] ^ lfsr_q[20] ^ 
lfsr_q[26] ^ lfsr_q[27] ^ lfsr_q[29] ^ lfsr_q[31] ^ data_in[0] ^ 
data_in[1] ^ data_in[6] ^ data_in[9] ^ data_in[13] ^ data_in[15] ^ 
data_in[16] ^ data_in[17] ^ data_in[19] ^ data_in[20] ^ data_in[26] ^ 
data_in[27] ^ data_in[29] ^ data_in[31];
lfsr_c[24] = lfsr_q[1] ^ lfsr_q[2] ^ lfsr_q[7] ^ lfsr_q[10] ^ lfsr_q[14] 
^ lfsr_q[16] ^ lfsr_q[17] ^ lfsr_q[18] ^ lfsr_q[20] ^ lfsr_q[21] ^ 
lfsr_q[27] ^ lfsr_q[28] ^ lfsr_q[30] ^ data_in[1] ^ data_in[2] ^ 
data_in[7] ^ data_in[10] ^ data_in[14] ^ data_in[16] ^ data_in[17] ^ 
data_in[18] ^ data_in[20] ^ data_in[21] ^ data_in[27] ^ data_in[28] ^ 
data_in[30];
lfsr_c[25] = lfsr_q[2] ^ lfsr_q[3] ^ lfsr_q[8] ^ lfsr_q[11] ^ lfsr_q[15] 
^ lfsr_q[17] ^ lfsr_q[18] ^ lfsr_q[19] ^ lfsr_q[21] ^ lfsr_q[22] ^ 
lfsr_q[28] ^ lfsr_q[29] ^ lfsr_q[31] ^ data_in[2] ^ data_in[3] ^ 
data_in[8] ^ data_in[11] ^ data_in[15] ^ data_in[17] ^ data_in[18] ^ 
data_in[19] ^ data_in[21] ^ data_in[22] ^ data_in[28] ^ data_in[29] ^ 
data_in[31];
lfsr_c[26] = lfsr_q[0] ^ lfsr_q[3] ^ lfsr_q[4] ^ lfsr_q[6] ^ lfsr_q[10] 
^ lfsr_q[18] ^ lfsr_q[19] ^ lfsr_q[20] ^ lfsr_q[22] ^ lfsr_q[23] ^ 
lfsr_q[24] ^ lfsr_q[25] ^ lfsr_q[26] ^ lfsr_q[28] ^ lfsr_q[31] ^ 
data_in[0] ^ data_in[3] ^ data_in[4] ^ data_in[6] ^ data_in[10] ^ 
data_in[18] ^ data_in[19] ^ data_in[20] ^ data_in[22] ^ data_in[23] ^ 
data_in[24] ^ data_in[25] ^ data_in[26] ^ data_in[28] ^ data_in[31];
lfsr_c[27] = lfsr_q[1] ^ lfsr_q[4] ^ lfsr_q[5] ^ lfsr_q[7] ^ lfsr_q[11] 
^ lfsr_q[19] ^ lfsr_q[20] ^ lfsr_q[21] ^ lfsr_q[23] ^ lfsr_q[24] ^ 
lfsr_q[25] ^ lfsr_q[26] ^ lfsr_q[27] ^ lfsr_q[29] ^ data_in[1] ^ 
data_in[4] ^ data_in[5] ^ data_in[7] ^ data_in[11] ^ data_in[19] ^ 
data_in[20] ^ data_in[21] ^ data_in[23] ^ data_in[24] ^ data_in[25] ^ 
data_in[26] ^ data_in[27] ^ data_in[29];
lfsr_c[28] = lfsr_q[2] ^ lfsr_q[5] ^ lfsr_q[6] ^ lfsr_q[8] ^ lfsr_q[12] 
^ lfsr_q[20] ^ lfsr_q[21] ^ lfsr_q[22] ^ lfsr_q[24] ^ lfsr_q[25] ^ 
lfsr_q[26] ^ lfsr_q[27] ^ lfsr_q[28] ^ lfsr_q[30] ^ data_in[2] ^ 
data_in[5] ^ data_in[6] ^ data_in[8] ^ data_in[12] ^ data_in[20] ^ 
data_in[21] ^ data_in[22] ^ data_in[24] ^ data_in[25] ^ data_in[26] ^ 
data_in[27] ^ data_in[28] ^ data_in[30];
lfsr_c[29] = lfsr_q[3] ^ lfsr_q[6] ^ lfsr_q[7] ^ lfsr_q[9] ^ lfsr_q[13] 
^ lfsr_q[21] ^ lfsr_q[22] ^ lfsr_q[23] ^ lfsr_q[25] ^ lfsr_q[26] ^ 
lfsr_q[27] ^ lfsr_q[28] ^ lfsr_q[29] ^ lfsr_q[31] ^ data_in[3] ^ 
data_in[6] ^ data_in[7] ^ data_in[9] ^ data_in[13] ^ data_in[21] ^ 
data_in[22] ^ data_in[23] ^ data_in[25] ^ data_in[26] ^ data_in[27] ^ 
data_in[28] ^ data_in[29] ^ data_in[31];
lfsr_c[30] = lfsr_q[4] ^ lfsr_q[7] ^ lfsr_q[8] ^ lfsr_q[10] ^ lfsr_q[14] 
^ lfsr_q[22] ^ lfsr_q[23] ^ lfsr_q[24] ^ lfsr_q[26] ^ lfsr_q[27] ^ 
lfsr_q[28] ^ lfsr_q[29] ^ lfsr_q[30] ^ data_in[4] ^ data_in[7] ^ 
data_in[8] ^ data_in[10] ^ data_in[14] ^ data_in[22] ^ data_in[23] ^ 
data_in[24] ^ data_in[26] ^ data_in[27] ^ data_in[28] ^ data_in[29] ^ 
data_in[30];
lfsr_c[31] = lfsr_q[5] ^ lfsr_q[8] ^ lfsr_q[9] ^ lfsr_q[11] ^ lfsr_q[15] 
^ lfsr_q[23] ^ lfsr_q[24] ^ lfsr_q[25] ^ lfsr_q[27] ^ lfsr_q[28] ^ 
lfsr_q[29] ^ lfsr_q[30] ^ lfsr_q[31] ^ data_in[5] ^ data_in[8] ^ 
data_in[9] ^ data_in[11] ^ data_in[15] ^ data_in[23] ^ data_in[24] ^ 
data_in[25] ^ data_in[27] ^ data_in[28] ^ data_in[29] ^ data_in[30] ^ 
data_in[31];

end // always

always @(posedge clk, posedge rst) begin
if(rst) begin
lfsr_q <= {32{1'b1}};
end
else begin
lfsr_q <= crc_en ? lfsr_c : lfsr_q;
end
end // always
endmodule // crc
i ve written test bench as follows
`timescale 1ns / 1ps

//////////////////////////////////////////////////////////////////////// 
////////
// Company:
// Engineer:
//
// Create Date: 10:56:09 02/14/2016
// Design Name: crc
// Module Name: 
C:/Users/DINITA/Desktop/ajit_xilinx/14-02-16/crc32bit/tb.v
// Project Name: crc32bit
// Target Device:
// Tool versions:
// Description:
//
// Verilog Test Fixture created by ISE for module: crc
//
// Dependencies:
//
// Revision:
// Revision 0.01 - File Created
// Additional Comments:
//
//////////////////////////////////////////////////////////////////////// 
////////

module tb_v;

// Inputs
reg [31:0] data_in;
reg crc_en;
reg rst;
reg clk;

// Outputs
wire [31:0] crc_out;

// Instantiate the Unit Under Test (UUT)
crc uut (
.data_in(data_in),
.crc_en(crc_en),
.crc_out(crc_out),
.rst(rst),
.clk(clk)
);

initial begin
// Initialize Inputs
#1 clk = 0;
#1 crc_en = 0;
#1 rst=0;
data_in =32'h0000000000000000;
forever begin
data_in =32'h01234567891234567;
#1 clk = ~clk;
#1 rst = ~rst;
#1 crc_en = ~crc_en;

$finish;
end

// Wait 100 ns for global reset to finish
#1000 $stop;

// Add stimulus here

end
initial
$monitor("At time %2t, crc_en = %d, rst = %d, data_in = %d, crc_out = 
%d",
$time, crc_en, rst, data_in, crc_out);

endmodule

i didnt get correct waveform
please help me
thanks!!!!

Ajit S. wrote:
> i ve written verilog code for crc32
Sure?
It looks to me like you copied the Verilog code from 
http://www.outputlogic.com and you ripped of the disclaimer.
You can be pretty sure, that even your teacher knows that website...

> i didnt get correct waveform
What do you expect? And what do you get instead?