[raggedstone] / dhwk / source / ser_par_con.vhd

-- $Id: ser_par_con.vhd,v 1.4 2007-03-11 13:23:11 sithglan Exp $

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;

entity SER_PAR_CON is
        port
        (
                PCI_CLOCK :in std_logic;
                RESET :in std_logic;
                SPC_ENABLE :in std_logic; -- Driver Enable Sender/Receiver
                SYNC_R_FIFO_FFn :in std_logic; -- FIFO Full Flag (low active)
                SERIAL_IN :in std_logic; -- Serial Input
                R_FIFO_WRITEn :out std_logic; -- FIFO Write (low active)
                SPC_RDY_OUT :out std_logic; -- Ready to Receive Data
                PAR_OUT :out std_logic_vector(7 downto 0)
        );
end entity SER_PAR_CON;


architecture SER_PAR_CON_DESIGN of SER_PAR_CON is

-- constant STATE_RECV :std_logic_vector(3 downto 0) := "0001";
        constant STATE_RECV_START_BIT :std_logic_vector(3 downto 0) := "0010";
        constant STATE_RECV_BIT_0 :std_logic_vector(3 downto 0) := "0011";
        constant STATE_RECV_BIT_1 :std_logic_vector(3 downto 0) := "0100";
        constant STATE_RECV_BIT_2 :std_logic_vector(3 downto 0) := "0101";
        constant STATE_RECV_BIT_3 :std_logic_vector(3 downto 0) := "0110";
        constant STATE_RECV_BIT_4 :std_logic_vector(3 downto 0) := "0111";
        constant STATE_RECV_BIT_5 :std_logic_vector(3 downto 0) := "1000";
        constant STATE_RECV_BIT_6 :std_logic_vector(3 downto 0) := "1001";
        constant STATE_RECV_BIT_7 :std_logic_vector(3 downto 0) := "1010";
        constant STATE_RECV_FIFOFULL :std_logic_vector(3 downto 0) := "1011";

        signal COUNT :std_logic_vector (3 downto 0);
        signal STATE :std_logic_vector (3 downto 0);
        signal STARTBIT :std_logic_vector (3 downto 0);


        attribute syn_state_machine:boolean;
        attribute syn_state_machine of STATE: signal is false;
        attribute syn_state_machine of COUNT: signal is false;

begin

        process(PCI_CLOCK)
        begin
                if (rising_edge(PCI_CLOCK)) then
                        if ("0000" < COUNT) then
                                COUNT <= COUNT - 1;
                        end if;

 -- war nicht das Problem des Datenverlusts
 -- if (R_FIFO_WRITEn = '0' and COUNT = "0000") then
 -- R_FIFO_WRITEn <= '1';
 --- end if;

                        if (RESET = '1') then
                                STATE <= STATE_RECV_START_BIT;
                                COUNT <= "0000";
                                R_FIFO_WRITEn <= '1';

                        elsif (SPC_ENABLE = '1') then

                                if (STATE = STATE_RECV_START_BIT) then
                                        R_FIFO_WRITEn <= '1';
                                        if (STARTBIT = "0011") then
                                                COUNT <= "0011";
                                                STATE <= STATE_RECV_BIT_0;
                                        end if;

                                elsif (STATE = STATE_RECV_FIFOFULL) then
                                        if (SYNC_R_FIFO_FFn = '1') then
                                                R_FIFO_WRITEn <= '0';
                                                STATE <= STATE_RECV_START_BIT;
                                        end if;

                                elsif (COUNT = "0000") then
                                        COUNT <= "0011";
                                        case STATE is

                                        when STATE_RECV_BIT_0 =>
                                                PAR_OUT(0) <= STARTBIT(0);
                                                STATE <= STATE_RECV_BIT_1;

                                        when STATE_RECV_BIT_1 =>
                                                PAR_OUT(1) <= STARTBIT(0);
                                                STATE <= STATE_RECV_BIT_2;

                                        when STATE_RECV_BIT_2 =>
                                                PAR_OUT(2) <= STARTBIT(0);
                                                STATE <= STATE_RECV_BIT_3;

                                        when STATE_RECV_BIT_3 =>
                                                PAR_OUT(3) <= STARTBIT(0);
                                                STATE <= STATE_RECV_BIT_4;

                                        when STATE_RECV_BIT_4 =>
                                                PAR_OUT(4) <= STARTBIT(0);
                                                STATE <= STATE_RECV_BIT_5;

                                        when STATE_RECV_BIT_5 =>
                                                PAR_OUT(5) <= STARTBIT(0);
                                                STATE <= STATE_RECV_BIT_6;

                                        when STATE_RECV_BIT_6 =>
                                                PAR_OUT(6) <= STARTBIT(0);
                                                STATE <= STATE_RECV_BIT_7;

                                        when STATE_RECV_BIT_7 =>
                                                PAR_OUT(7) <= STARTBIT(0);

                                                if (SYNC_R_FIFO_FFn = '1') then
                                                        STATE <= STATE_RECV_START_BIT;
                                                        R_FIFO_WRITEn <= '0';
                                                else
                                                        STATE <= STATE_RECV_FIFOFULL;
                                                end if;

                                        when others =>
                                                STATE <= STATE_RECV_START_BIT;

                                        end case;
                                end if; -- COUNT
                        end if; -- RESET ... / SPC_ENABLE ...
                end if; -- PCI_CLOCK ...
        end process;

        process(PCI_CLOCK)
        begin
                if (rising_edge(PCI_CLOCK)) then
                        SPC_RDY_OUT <= SPC_ENABLE AND SYNC_R_FIFO_FFn;
                end if;
        end process;


        process(PCI_CLOCK)
        begin
                if (rising_edge(PCI_CLOCK)) then
                        if (RESET = '1') then
                                STARTBIT <= "0000";
                        else
                                STARTBIT(0) <= SERIAL_IN;
                                STARTBIT(1) <= STARTBIT(0);
                                STARTBIT(2) <= STARTBIT(1);
                                STARTBIT(3) <= STARTBIT(2);
                        end if;
                end if;
        end process;

end architecture SER_PAR_CON_DESIGN;
Commit	Line	Data
e687cadb	1	-- $Id: ser_par_con.vhd,v 1.4 2007-03-11 13:23:11 sithglan Exp $
696ded12	2
	3	library ieee;
	4	use ieee.std_logic_1164.all;
	5	use ieee.std_logic_unsigned.all;
	6
	7	entity SER_PAR_CON is
2612d712	8	port
	9	(
	10	PCI_CLOCK :in std_logic;
	11	RESET :in std_logic;
	12	SPC_ENABLE :in std_logic; -- Driver Enable Sender/Receiver
	13	SYNC_R_FIFO_FFn :in std_logic; -- FIFO Full Flag (low active)
	14	SERIAL_IN :in std_logic; -- Serial Input
	15	R_FIFO_WRITEn :out std_logic; -- FIFO Write (low active)
	16	SPC_RDY_OUT :out std_logic; -- Ready to Receive Data
	17	PAR_OUT :out std_logic_vector(7 downto 0)
	18	);
	19	end entity SER_PAR_CON;
696ded12	20
	21
	22	architecture SER_PAR_CON_DESIGN of SER_PAR_CON is
	23
2612d712	24	-- constant STATE_RECV :std_logic_vector(3 downto 0) := "0001";
	25	constant STATE_RECV_START_BIT :std_logic_vector(3 downto 0) := "0010";
	26	constant STATE_RECV_BIT_0 :std_logic_vector(3 downto 0) := "0011";
	27	constant STATE_RECV_BIT_1 :std_logic_vector(3 downto 0) := "0100";
	28	constant STATE_RECV_BIT_2 :std_logic_vector(3 downto 0) := "0101";
	29	constant STATE_RECV_BIT_3 :std_logic_vector(3 downto 0) := "0110";
	30	constant STATE_RECV_BIT_4 :std_logic_vector(3 downto 0) := "0111";
	31	constant STATE_RECV_BIT_5 :std_logic_vector(3 downto 0) := "1000";
	32	constant STATE_RECV_BIT_6 :std_logic_vector(3 downto 0) := "1001";
	33	constant STATE_RECV_BIT_7 :std_logic_vector(3 downto 0) := "1010";
	34	constant STATE_RECV_FIFOFULL :std_logic_vector(3 downto 0) := "1011";
696ded12	35
2612d712	36	signal COUNT :std_logic_vector (3 downto 0);
	37	signal STATE :std_logic_vector (3 downto 0);
	38	signal STARTBIT :std_logic_vector (3 downto 0);
696ded12	39
696ded12	40
2612d712	41	attribute syn_state_machine:boolean;
	42	attribute syn_state_machine of STATE: signal is false;
	43	attribute syn_state_machine of COUNT: signal is false;
696ded12	44
	45	begin
	46
2612d712	47	process(PCI_CLOCK)
2612d712	48	begin
e687cadb	49	if (rising_edge(PCI_CLOCK)) then
2612d712	50	if ("0000" < COUNT) then
	51	COUNT <= COUNT - 1;
	52	end if;
	53
	54	-- war nicht das Problem des Datenverlusts
	55	-- if (R_FIFO_WRITEn = '0' and COUNT = "0000") then
	56	-- R_FIFO_WRITEn <= '1';
	57	--- end if;
	58
	59	if (RESET = '1') then
	60	STATE <= STATE_RECV_START_BIT;
	61	COUNT <= "0000";
	62	R_FIFO_WRITEn <= '1';
	63
	64	elsif (SPC_ENABLE = '1') then
	65
	66	if (STATE = STATE_RECV_START_BIT) then
	67	R_FIFO_WRITEn <= '1';
	68	if (STARTBIT = "0011") then
	69	COUNT <= "0011";
	70	STATE <= STATE_RECV_BIT_0;
	71	end if;
696ded12	72
2612d712	73	elsif (STATE = STATE_RECV_FIFOFULL) then
696ded12	74	if (SYNC_R_FIFO_FFn = '1') then
2612d712	75	R_FIFO_WRITEn <= '0';
2612d712	76	STATE <= STATE_RECV_START_BIT;
696ded12	77	end if;
696ded12	78
2612d712	79	elsif (COUNT = "0000") then
	80	COUNT <= "0011";
	81	case STATE is
	82
	83	when STATE_RECV_BIT_0 =>
	84	PAR_OUT(0) <= STARTBIT(0);
	85	STATE <= STATE_RECV_BIT_1;
	86
	87	when STATE_RECV_BIT_1 =>
	88	PAR_OUT(1) <= STARTBIT(0);
	89	STATE <= STATE_RECV_BIT_2;
	90
	91	when STATE_RECV_BIT_2 =>
	92	PAR_OUT(2) <= STARTBIT(0);
	93	STATE <= STATE_RECV_BIT_3;
	94
	95	when STATE_RECV_BIT_3 =>
	96	PAR_OUT(3) <= STARTBIT(0);
	97	STATE <= STATE_RECV_BIT_4;
	98
	99	when STATE_RECV_BIT_4 =>
	100	PAR_OUT(4) <= STARTBIT(0);
	101	STATE <= STATE_RECV_BIT_5;
	102
	103	when STATE_RECV_BIT_5 =>
	104	PAR_OUT(5) <= STARTBIT(0);
	105	STATE <= STATE_RECV_BIT_6;
	106
	107	when STATE_RECV_BIT_6 =>
	108	PAR_OUT(6) <= STARTBIT(0);
	109	STATE <= STATE_RECV_BIT_7;
	110
	111	when STATE_RECV_BIT_7 =>
	112	PAR_OUT(7) <= STARTBIT(0);
	113
	114	if (SYNC_R_FIFO_FFn = '1') then
	115	STATE <= STATE_RECV_START_BIT;
	116	R_FIFO_WRITEn <= '0';
	117	else
	118	STATE <= STATE_RECV_FIFOFULL;
	119	end if;
	120
	121	when others =>
	122	STATE <= STATE_RECV_START_BIT;
	123
	124	end case;
	125	end if; -- COUNT
	126	end if; -- RESET ... / SPC_ENABLE ...
	127	end if; -- PCI_CLOCK ...
	128	end process;
	129
	130	process(PCI_CLOCK)
	131	begin
e687cadb	132	if (rising_edge(PCI_CLOCK)) then
2612d712	133	SPC_RDY_OUT <= SPC_ENABLE AND SYNC_R_FIFO_FFn;
	134	end if;
	135	end process;
	136
	137
	138	process(PCI_CLOCK)
	139	begin
e687cadb	140	if (rising_edge(PCI_CLOCK)) then
2612d712	141	if (RESET = '1') then
	142	STARTBIT <= "0000";
	143	else
	144	STARTBIT(0) <= SERIAL_IN;
	145	STARTBIT(1) <= STARTBIT(0);
	146	STARTBIT(2) <= STARTBIT(1);
	147	STARTBIT(3) <= STARTBIT(2);
	148	end if;
	149	end if;
	150	end process;
696ded12	151
696ded12	152	end architecture SER_PAR_CON_DESIGN;