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[/] [ccsds_rxtxsoc/] [trunk/] [ccsds_tx_header.vhd] - Blame information for rev 2

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1 2 zguig52 
-------------------------------
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---- Project: EurySPACE CCSDS RX/TX with wishbone interface
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---- Design Name: ccsds_tx_header
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---- Version: 1.0.0
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---- Description:
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---- TBD
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-------------------------------
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---- Author(s):
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---- Guillaume REMBERT
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-------------------------------
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---- Licence:
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---- MIT
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-------------------------------
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---- Changes list:
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---- 2016/02/28: initial release
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---- 2016/10/21: rework
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---- 2016/11/03: add idle data flag
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-------------------------------
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--TODO: static fixed virtual channel now - implement virtual channel service
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--TODO: secondary header
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--TODO: security header
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--TRANSFER FRAME PRIMARY HEADER => 6 octets
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--  \  MASTER CHANNEL ID => 12 bits
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--      \ TRANSFER FRAME VERSION NUMBER => 2 bits
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--      \ SPACECRAFT ID => 10 bits
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--  \ VIRTUAL CHANNEL ID => 3 bits
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--  \ OCF FLAG => 1 bit
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--  \ MASTER CHANNEL FRAME COUNT => 1 octet
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--  \ VIRTUAL CHANNEL FRAME COUNT => 1 octet
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--  \ TRANSFER FRAME DATA FIELD STATUS => 2 octets
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--      \ TRANSFER FRAME SECONDARY HEADER FLAG => 1 bit
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--      \ SYNC FLAG => 1 bit
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--      \ PACKET ORDER FLAG => 1 bit
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--      \ SEGMENT LENGTH ID => 2 bits
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--      \ FIRST HEADER POINTER => 11 bits
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--[OPT] TRANSFER FRAME SECONDARY HEADER => up to 64 octets
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--       \ TRANSFER FRAME SECONDARY HEADER ID => 1 octet
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--             \ TRANSFER FRAME SECONDARY HEADER VERSION NUMBER => 2 bits
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--             \ TRANSFER FRAME SECONDARY HEADER LENGTH => 6 bits
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--       \ TRANSFER FRAME SECONDARY HEADER DATA FIELD => up to 63 octets
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--[OPT] SECURITY HEADER
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-- libraries used
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library ieee;
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use ieee.std_logic_1164.all;
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use ieee.numeric_std.all;
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--=============================================================================
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-- Entity declaration for ccsds_tx / unitary tx header inputs and outputs
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--=============================================================================
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entity ccsds_tx_header is
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  generic(
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    CCSDS_TX_HEADER_LENGTH: integer; -- in Bytes
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    CCSDS_TX_HEADER_MCI_TFVN: std_logic_vector(2-1 downto 0) := "00"; -- Transfer Frame Version Number value
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    CCSDS_TX_HEADER_MCI_SID: std_logic_vector(10-1 downto 0) := "1100110011"; -- Spacecraft ID value
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    CCSDS_TX_HEADER_MCFC_LENGTH: integer := 8; -- Master Channel Frame Count length - in bits
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    CCSDS_TX_HEADER_OCFF: std_logic := '0'; -- Operationnal Control Field Flag
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    CCSDS_TX_HEADER_VCI: std_logic_vector(3-1 downto 0) := "000"; -- Virtual Channel Identifier value
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    CCSDS_TX_HEADER_VCFC_LENGTH: integer := 8; -- Virtual Channel Frame Count length - in bits
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    CCSDS_TX_HEADER_TFDFS_LENGTH: integer := 16; -- Transfer Frame Data Field Status length - in bits
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    CCSDS_TX_HEADER_TFDFS_POF: std_logic := '0'; -- Packet Order Flag
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    CCSDS_TX_HEADER_TFDFS_SF: std_logic := '0'; -- Synchronization Flag
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    CCSDS_TX_HEADER_TFDFS_SLI: std_logic_vector(1 downto 0) := "11"; -- Segment Length Identifier
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    CCSDS_TX_HEADER_TFDFS_TFSHF: std_logic := '0' -- Transfer Frame Secondary Header Flag
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  );
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  port(
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    -- inputs
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    clk_i: in std_logic;
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    idl_i: in std_logic;
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    nxt_i: in std_logic;
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    rst_i: in std_logic;
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    -- outputs
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    dat_o: out std_logic_vector(CCSDS_TX_HEADER_LENGTH*8-1 downto 0);
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    dat_val_o: out std_logic
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  );
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end ccsds_tx_header;
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--=============================================================================
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-- architecture declaration / internal components and connections
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--=============================================================================
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architecture rtl of ccsds_tx_header is
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-- internal variable signals
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-- components instanciation and mapping
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  begin
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-- presynthesis checks
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    CHKHEADERP0 : if CCSDS_TX_HEADER_LENGTH*8 /= (CCSDS_TX_HEADER_MCI_TFVN'length + CCSDS_TX_HEADER_MCI_SID'length + CCSDS_TX_HEADER_VCI'length + CCSDS_TX_HEADER_MCFC_LENGTH + CCSDS_TX_HEADER_VCFC_LENGTH + CCSDS_TX_HEADER_TFDFS_LENGTH + 1) generate
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      process
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      begin
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        report "ERROR: HEADER LENGTH IS DIFFERENT OF TOTAL SUBELEMENTS LENGTH" severity failure;
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        wait;
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      end process;
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    end generate CHKHEADERP0;
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-- internal processing
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    --=============================================================================
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    -- Begin of headerp
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    -- Generate valid headers
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    --=============================================================================
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    -- read: rst_i, nxt_i
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    -- write: dat_val_o, dat_o
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    -- r/w:
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    HEADERP : process (clk_i)
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    variable header_mci_tfvn: std_logic_vector(CCSDS_TX_HEADER_MCI_TFVN'length-1 downto 0) := CCSDS_TX_HEADER_MCI_TFVN; -- Transfer Frame Version Number
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    variable header_mci_sid: std_logic_vector(CCSDS_TX_HEADER_MCI_SID'length-1 downto 0) := CCSDS_TX_HEADER_MCI_SID; -- Spacecraft ID
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    variable header_vci: std_logic_vector(CCSDS_TX_HEADER_VCI'length-1 downto 0) := CCSDS_TX_HEADER_VCI; -- Virtual Channel Identifier
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    variable header_ocff: std_logic := CCSDS_TX_HEADER_OCFF; -- Operationnal Control Field Flag
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    variable header_mcfc: integer range 0 to (2**CCSDS_TX_HEADER_MCFC_LENGTH)-1 := 0; -- Master Channel Frame Count
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    variable header_vcfc: integer range 0 to (2**CCSDS_TX_HEADER_VCFC_LENGTH)-1 := 0; -- Virtual Channel Frame Count
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    variable header_tfdfs_fhp: std_logic_vector(CCSDS_TX_HEADER_TFDFS_LENGTH-6 downto 0) := "00000000000"; -- First Header Pointer / 11111111110 when idle data inside only
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    begin
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      -- on each clock rising edge
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      if rising_edge(clk_i) then
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        -- reset signal received
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        if (rst_i = '1') then
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          dat_o <= (others => '0');
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          dat_val_o <= '0';
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          header_mci_tfvn := CCSDS_TX_HEADER_MCI_TFVN;
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          header_mci_sid := CCSDS_TX_HEADER_MCI_SID;
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          header_vci := CCSDS_TX_HEADER_VCI;
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          header_ocff := '1';
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          header_mcfc := 0;
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          header_vcfc := 0;
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          header_tfdfs_fhp := "00000000000";
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        else
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          if (nxt_i = '1') then
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            if(idl_i = '1') then
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              header_tfdfs_fhp := "11111111110";
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            else
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              header_tfdfs_fhp := "00000000000";
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            end if;
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            dat_val_o <= '1';
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            dat_o(CCSDS_TX_HEADER_LENGTH*8-1 downto CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length) <= header_mci_tfvn;
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            dat_o(CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-1 downto CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length) <= header_mci_sid;
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            dat_o(CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length-1 downto CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length-CCSDS_TX_HEADER_VCI'length) <= header_vci;
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            dat_o(CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length-CCSDS_TX_HEADER_VCI'length-1) <= header_ocff;
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            dat_o(CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length-CCSDS_TX_HEADER_VCI'length-1-1 downto CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length-CCSDS_TX_HEADER_VCI'length-1-CCSDS_TX_HEADER_MCFC_LENGTH) <= std_logic_vector(to_unsigned(header_mcfc,CCSDS_TX_HEADER_MCFC_LENGTH));
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            dat_o(CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length-CCSDS_TX_HEADER_VCI'length-1-CCSDS_TX_HEADER_MCFC_LENGTH-1 downto CCSDS_TX_HEADER_LENGTH*8-CCSDS_TX_HEADER_MCI_TFVN'length-CCSDS_TX_HEADER_MCI_SID'length-CCSDS_TX_HEADER_VCI'length-1-CCSDS_TX_HEADER_MCFC_LENGTH-CCSDS_TX_HEADER_VCFC_LENGTH) <= std_logic_vector(to_unsigned(header_vcfc,CCSDS_TX_HEADER_VCFC_LENGTH));
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            dat_o(CCSDS_TX_HEADER_TFDFS_LENGTH-1 downto CCSDS_TX_HEADER_TFDFS_LENGTH-5) <= CCSDS_TX_HEADER_TFDFS_TFSHF & CCSDS_TX_HEADER_TFDFS_SF & CCSDS_TX_HEADER_TFDFS_POF & CCSDS_TX_HEADER_TFDFS_SLI;
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            dat_o(CCSDS_TX_HEADER_TFDFS_LENGTH-6 downto 0) <= header_tfdfs_fhp;
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            if (header_mcfc = (2**CCSDS_TX_HEADER_MCFC_LENGTH)-1) then
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              header_mcfc := 0;
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            else
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              header_mcfc := header_mcfc + 1;
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            end if;
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            if (header_vcfc = (2**CCSDS_TX_HEADER_VCFC_LENGTH)-1) then
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              header_vcfc := 0;
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            else
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              header_vcfc := header_vcfc + 1;
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            end if;
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          else
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            dat_val_o <= '0';
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          end if;
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        end if;
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      end if;
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    end process;
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end rtl;

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