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Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
9 years ago

Question Regarding to the MAX V eval board.

I am new user try to run my simple test on Altera Max V eval kit. I wrote a simple code want to verify a simple function:

http://www.alteraforum.com/forum/attachment.php?attachmentid=12665&stc=1

in file counter.v 

module counter( CLOCK_10KHZ, counter_out, RESET);
input CLOCK_10KHZ;
input RESET;
output  counter_out;
reg  counter_out;
always @(posedge CLOCK_10KHZ) begin
    if (!RESET)    begin        //Reset button is not pushed
        counter_out <=# 1 ~(counter_out + 1); //increment counter, neg light up the LED, and pos turn off
    end
    else begin
        counter_out <=# 1 ~16'b0;
    end
end
endmodule

When I push the reset button, the LED goes off, that proved clock trigger signal is correct, however, after I release the PB1, all LEDs still on and didn't change status(It suppose to light up and turn off while counter increasing).

Platform: Windows 7,64bit, Quartus Prime Lite Edition 16.0. MAX V Eval Board

Could anyone take a look what might be wrong with my program?

Thank you!

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    counter_out <=# 1 ~(counter_out + 1);
    This is not doing what you want it too and is just resulting in 'counter_out' holding a static value (both in and out of reset).

    I might suggest that you've not simulated this. Doing so would have quickly pointed out your fault.

    Firstly, remove the "#1" from your code. This means nothing to your MAX V device or any logic synthesizer.

    Secondly, change the above statement to a simple 

    counter_out <= counter_out + 1;

    Then, outside of that always block, deal with the inversion that the LEDs on your hardware require. 

    assign led = ~counter_out;

    Finally, swap 'led' for 'counter_out' in your module's port list.

    Cheers,

    Alex