Forum Discussion

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

CRC blocks 0 / 1 (Fitter Resource Usage Summary)

I'm using Quartus II 9.1sp2, and compiling for a Cyclone II EP2C5T144C8.

In the Fitter Resource Usage Summary it lists an entry that says:

CRC blocks: 0 / 1 (0%)

In the design options I already turned on the automatic periodic integrity check.

The question now is, what is this unused CRC block, and how could I make use of it?

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Hi,

    See Application Note 539.

    AN 539: Test Methodology of Error Detection and Recovery using CRC in

    Altera FPGA Devices.

    Page 7:

    Using the Error Detection CRC Feature.

    You can use a "CRC Block WYSIWYG Atom" to interface from

    user logic to the error detection circuit.

    There is a Template under "C:\altera\81\quartus\libraries\vhdl\wysiwyg"

    ------------------------------------------------------------------

    -- cycloneiii_crcblock parameterized megafunction component declaration

    -- Generated with 'mega_defn_creator' loader - do not edit

    ------------------------------------------------------------------

    component cycloneiii_crcblock

    generic (

    lpm_type : string := "cycloneiii_crcblock" );

    port (

    clk : in std_logic := '0';

    crcerror : out std_logic;

    ldsrc : in std_logic := '0';

    regout : out std_logic;

    shiftnld : in std_logic := '0'

    );

    end component;