Unable to read the data from AVALON FIFO MEMORY under on-chip memory

@Daixiwen. The above FIFO design is working. LIKEWISE, i have tried the same design.

Working Design BLOCK diagram

In following design, i am generating Trigger signal (500ns) and Counter data using Verilog code. Then need to read the data in NIOS console using FIFO.

Code

module Counter(
    input clk,
	 input enable,
    input reset,
    output reg[31:0] Final_value,
    output reg trig
    );
    reg[31:0] counter_out;
    reg [7:0] temp;
    reg [31:0] counter_result;
    wire temp1;
    wire temp2; 
       
    always@(posedge clk or negedge reset)
    begin
    if(~reset)
        begin
        trig<=0;
        temp<=0;
        counter_out<=0;
        end
    else if(enable==1'b1)
        begin
        counter_out<=counter_out+1;
        temp<=temp+1;
        if(temp==25)
            begin
            temp<=0;
            trig<=~trig;
            end
        end
        end 
	 assign temp1=trig;
	 assign temp2=temp1&&clk;
	 always@(posedge temp2 or negedge reset)
	 if(~reset)
	    counter_result<=0;   
	  else 
	 begin
        counter_result<=counter_result+1;
     end
  always@(posedge trig or negedge reset)
  if(~reset)
       Final_value<=0;  
   else 
  begin
       Final_value<=counter_result;
  end
endmodule

FIFO DESIGN [NOT working]

Can anyone point out me the error in my design. Please suggest me.

Hi,

You can try out the example here https://www.intel.co.jp/content/dam/altera-www/global/ja_JP/pdfs/literature/ug/ug_nios2_flash_programmer.pdf to see if you able read the correct memory.

Thanks​

You write to the fifo faster than you read back from it, so you will miss a lot of the counter values. In your design the write signal is always 1, meaning you write a value on each clock cycle. On the other side, as you are using a CPU to read back the data, there will be multiple clock cycles between two reads.

@Daixiwen. Thanks for your response. If you could tell me the solution to sort my problem means, it will be helpful to me.

You can't write on each clock cycle. You should change your design to check whether the fifo is full or not and only write the value (and increment the counter) when the fifo is not full.

>>You should change your design to check whether the fifo is full or not.

I am new to the Altera. So can you tell me how can the design should be modified, or else any design examples. Please guide me step by step.

Thanks.

Thanks Daixiwen, I am able to print counter data in NIOS console.