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~\Desktop\gray.v.html /*Logic to convert binary numbers into Gray coded binary numbers is implemented in the following Verilog Code.
*/
module binary2gray();
reg clk;
reg rstn;
reg [5:0] counter_binary, counter_binary_reg, counter_gray, counter_gray_reg;
integer count, file_wr;

/* Initial block to generate clock and reset */ 
initial  begin
    clk = 0; rstn = 0;  #100 rstn = 1;
    forever begin
        #10 clk = !clk; 
 end end    

/* Synchronous Logic for registering the data and incrementing the counter for binary data */
always @ (posedge clk or negedge rstn)
begin
    if (!rstn) begin
        counter_binary_reg <= 'b0;
        counter_gray_reg <= 'b0;  end
    else begin 
        counter_binary_reg <= counter_binary + 1;
        counter_gray_reg <= counter_gray;
        $display("binary number= 6'b%b : gray en-coded binary number = 6'b%b", counter_binary_reg, counter_gray_reg);   end end

/* Logic is to get Gray code from Binary code */
function[5:0] binary2gray ;
    input[5:0] value;
    integer i;
    begin 
        binary2gray[5] = value[5];
        for (i=5; i>0; i = i - 1)
            binary2gray[i-1] = value[i] ^ value[i - 1];
    end
endfunction

/* Get gray encoded output */
always @(*)
begin 
  counter_gray = counter_gray_reg;
  counter_binary = counter_binary_reg;
  counter_gray = binary2gray(counter_binary_reg); end
endmodule

Verilog Binary to Gray Code conversion example. Click here to get 0-100 binary-gray-decimal conversion example
LTE - Long Term Evolution topics from here
Interview Questions. Main, FPGA, Digital Fundamentals
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A function is discussed below to convert binary number to gray code number. The function is then used in combinational RTL logic. This kind of conversions are widely used in digital design to implement asynchronous clock crossing interfaces. The gray code primarily used to convert counter values before sending across the async interface. With this technique only one bit is allowed to change and it limits the error to +/- 1.

SystemVerilog

Parameters passing, defparam & localparam

Alias, Array, Assertions

 

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Testbench.
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