mt47h64m16.vhd

vhdl cod for ram.For sp3e

        --mode registers
        SHARED VARIABLE MR : std_logic_vector(12 DOWNTO 0) := (OTHERS => '0');
        SHARED VARIABLE EMR : std_logic_vector(12 DOWNTO 0);
        SHARED VARIABLE EMR2 : std_logic_vector(12 DOWNTO 0);
        SHARED VARIABLE EMR3 : std_logic_vector(12 DOWNTO 0);

        SHARED VARIABLE burst_len : natural RANGE 4 TO 8;--burst length

        SHARED VARIABLE active_forbid : boolean := FALSE;--more than 4 active
                                                         --commands during tFAW

        --bank, row and column of scheduled read or write operation
        SHARED VARIABLE current_bank : natural RANGE 0 TO BankNum;
        SHARED VARIABLE current_row : natural RANGE 0 TO RowNum;
        SHARED VARIABLE current_column : natural RANGE 0 TO ColNum;

        --bank, row and column of read operation that starts
        SHARED VARIABLE read_bank : natural RANGE 0 TO BankNum;
        SHARED VARIABLE read_row : natural RANGE 0 TO RowNum;
        SHARED VARIABLE read_column : natural RANGE 0 TO ColNum;

        TYPE write_sch_type IS ARRAY (0 TO 10) OF boolean;
        TYPE write_sch_bank_type IS ARRAY (0 TO BankNum) OF write_sch_type;
        --all scheduled reads within all banks
        SHARED VARIABLE read_sch : write_sch_bank_type :=
                                                  (OTHERS => (OTHERS => FALSE));
        --reads that should be preceeded by preamble
        SHARED VARIABLE preamble : write_sch_bank_type :=
                                                  (OTHERS => (OTHERS => TRUE));

        TYPE wait_read_type IS ARRAY (0 TO 10) OF std_ulogic;
        TYPE wait_read_bank_type IS ARRAY (0 TO BankNum) OF wait_read_type;
        --wait_read triggers process that counts remaining cycles to the
        --beggining of scheduled read when aditive latency has elapsed, and
        --read_delay keeps information of number of remaining cycles
        SIGNAL wait_read : wait_read_bank_type;
        SHARED VARIABLE read_delay : natural RANGE 0 TO 7;

        --needed for check if all rows were refreshed during refresh period
        SIGNAL Ref_per_start : std_ulogic := '0';
        SIGNAL Ref_per_expired : std_ulogic := '0';

        SHARED VARIABLE CK_rise : time := 0 ns;
        SHARED VARIABLE CK_period : time := 0 ns;

        TYPE Bank_state_type IS (precharged, refreshing, MRsetting, activating,
                                 active, reading, readingAP, writting,
                                 writtingAP, precharging, prechall);
        TYPE Bank_state_array_type IS ARRAY (0 TO BankNum) OF Bank_state_type;
        SHARED VARIABLE Curr_bank_state : Bank_state_array_type;
        SHARED VARIABLE Next_bank_state : Bank_state_array_type;

        SHARED VARIABLE SR_cond : boolean := FALSE;--self refresh can be entered
        SIGNAL SelfRefresh : boolean := FALSE;--self refresh active
        SIGNAL SR_exit : boolean := FALSE;--CKE high, self refresh exit
        SHARED VARIABLE SR_enter_cycle : boolean := FALSE;--clock can be
                                                          --turned off

        SIGNAL Pre_PD : boolean := FALSE;--precharge power down active
        SIGNAL Act_PD : boolean := FALSE;--active power down active
        SHARED VARIABLE Read_Start : boolean := FALSE;--read burst in progress,
        SIGNAL ReadStart : boolean := FALSE;          --no pd entry

        SIGNAL Reset : boolean := FALSE;--reset function active
        SHARED VARIABLE Reset_enter_cycle : boolean := FALSE;--clocks can be
                                                             --turned off

        SIGNAL SimulationEnd : boolean := FALSE;

        SIGNAL preamble_check : boolean := FALSE;
        SIGNAL postamble_check : boolean := FALSE;
        SIGNAL skew_check : boolean := FALSE;

        FUNCTION bool_to_nat(tm : boolean)
        RETURN natural IS
            VARIABLE Temp : natural;
        BEGIN
            Temp := 0;
            IF tm THEN
                Temp := 1;
            END IF;
            RETURN Temp;
        END bool_to_nat;

    BEGIN

    CK_DLL: PROCESS(CKDiff)
        VARIABLE Previous : time := 0 ns;
        VARIABLE TmpPer : time := 0 ns;
    BEGIN
        IF rising_edge(CKDiff) THEN
            TmpPer := NOW - Previous;
            IF TmpPer > 0 ns THEN
                CKPeriod <= TmpPer;
            END IF;
            Previous := NOW;
            CKHalfPer <= CKPeriod / 2;
            CKDLLDelay <= CKPeriod - tpd_CK_DQ1;
        END IF;
    END PROCESS CK_DLL;

    CK_temp: PROCESS(CKDiff) -- generating internal clock from DLL
    BEGIN
        CKtemp <= NOT CKDiff AFTER CKHalfPer;
    END PROCESS CK_temp;

    CKInt <= TRANSPORT CKtemp AFTER CKDLLDelay;

    Power_up: PROCESS(CK_stable)
    BEGIN
        IF CK_stable THEN
            PoweredUp <= TRUE AFTER 200 us;
        END IF;
    END PROCESS Power_up;

    Init_d: PROCESS(In_d)
    BEGIN
        IF In_d THEN
            Init_delay <= TRUE AFTER 400 ns;
        ELSE
            Init_delay <= FALSE;
        END IF;
    END PROCESS Init_d;

    DLLdelay: PROCESS(DLL_delay, CKDiff)
        VARIABLE cnt : natural;
    BEGIN
        IF rising_edge(DLL_delay) THEN
            cnt := 0;
            DLL_delay_elapsed <= FALSE;
        ELSIF rising_edge(CKDiff) AND NOT DLL_delay_elapsed THEN
            cnt := cnt + 1;
            IF cnt = 199 THEN
                DLL_delay_elapsed <= TRUE;
            END IF;
        END IF;
    END PROCESS DLLdelay;

    ----------------------------------------------------------------------------
    -- Main Behavior Process
    ----------------------------------------------------------------------------
    VITALBehaviour: PROCESS(CKDiff, LDQSDiff, LDQSIn, UDQSDiff, UDQSIn, DQIn_Lo,
                            DQIn_Hi, LDM, UDM, ODT, CKE, CSNeg, RASNeg, CASNeg,
                            WENeg, BAIn, AIn)

        -- Timing Check Variables
        VARIABLE Tviol_DQ0_LDQS    : X01 := '0';
        VARIABLE TD_DQ0_LDQS       : VitalTimingDataType;

        VARIABLE Tviol_DQ0_LDQS1   : X01 := '0';
        VARIABLE TD_DQ0_LDQS1      : VitalTimingDataType;

        VARIABLE Tviol_DQ1_LDQS    : X01 := '0';
        VARIABLE TD_DQ1_LDQS       : VitalTimingDataType;

        VARIABLE Tviol_DQ1_LDQS1   : X01 := '0';
        VARIABLE TD_DQ1_LDQS1      : VitalTimingDataType;

        VARIABLE Tviol_DQ0_UDQS    : X01 := '0';
        VARIABLE TD_DQ0_UDQS       : VitalTimingDataType;

        VARIABLE Tviol_DQ0_UDQS1   : X01 := '0';
        VARIABLE TD_DQ0_UDQS1      : VitalTimingDataType;

        VARIABLE Tviol_DQ1_UDQS    : X01 := '0';
        VARIABLE TD_DQ1_UDQS       : VitalTimingDataType;

        VARIABLE Tviol_DQ1_UDQS1   : X01 := '0';
        VARIABLE TD_DQ1_UDQS1      : VitalTimingDataType;

        VARIABLE Tviol_LDM0_LDQS   : X01 := '0';
        VARIABLE TD_LDM0_LDQS      : VitalTimingDataType;

        VARIABLE Tviol_LDM0_LDQS1  : X01 := '0';
        VARIABLE TD_LDM0_LDQS1     : VitalTimingDataType;

        VARIABLE Tviol_LDM1_LDQS   : X01 := '0';
        VARIABLE TD_LDM1_LDQS      : VitalTimingDataType;

        VARIABLE Tviol_LDM1_LDQS1  : X01 := '0';
        VARIABLE TD_LDM1_LDQS1     : VitalTimingDataType;

        VARIABLE Tviol_UDM0_UDQS   : X01 := '0';
        VARIABLE TD_UDM0_UDQS      : VitalTimingDataType;

        VARIABLE Tviol_UDM0_UDQS1  : X01 := '0';
        VARIABLE TD_UDM0_UDQS1     : VitalTimingDataType;

        VARIABLE Tviol_UDM1_UDQS   : X01 := '0';
        VARIABLE TD_UDM1_UDQS      : VitalTimingDataType;

        VARIABLE Tviol_UDM1_UDQS1  : X01 := '0';
        VARIABLE TD_UDM1_UDQS1     : VitalTimingDataType;

        VARIABLE Tviol_ODT_CK      : X01 := '0';
        VARIABLE TD_ODT_CK         : VitalTimingDataType;

        VARIABLE Tviol_CKE_CK      : X01 := '0';
        VARIABLE TD_CKE_CK         : VitalTimingDataType;

        VARIABLE Tviol_CSNeg_CK    : X01 := '0';
        VARIABLE TD_CSNeg_CK       : VitalTimingDataType;

        VARIABLE Tviol_RASNeg_CK   : X01 := '0';
        VARIABLE TD_RASNeg_CK      : VitalTimingDataType;

        VARIABLE Tviol_CASNeg_CK   : X01 := '0';
        VARIABLE TD_CASNeg_CK      : VitalTimingDataType;

        VARIABLE Tviol_WENeg_CK    : X01 := '0';
        VARIABLE TD_WENeg_CK       : VitalTimingDataType;

        VARIABLE Tviol_BA0_CK      : X01 := '0';
        VARIABLE TD_BA0_CK         : VitalTimingDataType;

        VARIABLE Tviol_A0_CK       : X01 := '0';
        VARIABLE TD_A0_CK          : VitalTimingDataType;

        VARIABLE Tviol_LDQS_CK3    : X01 := '0';
        VARIABLE TD_LDQS_CK3       : VitalTimingDataType;

        VARIABLE Tviol_LDQS_CK4    : X01 := '0';
        VARIABLE TD_LDQS_CK4       : VitalTimingDataType;

        VARIABLE Tviol_LDQS_CK5    : X01 := '0';
        VARIABLE TD_LDQS_CK5       : VitalTimingDataType;

        VARIABLE Tviol_LDQS_CK6    : X01 := '0';
        VARIABLE TD_LDQS_CK6       : VitalTimingDataType;

        VARIABLE Tviol_LDQS1_CK3   : X01 := '0';
        VARIABLE TD_LDQS1_CK3      : VitalTimingDataType;

        VARIABLE Tviol_LDQS1_CK4   : X01 := '0';
        VARIABLE TD_LDQS1_CK4      : VitalTimingDataType;

        VARIABLE Tviol_LDQS1_CK5   : X01 := '0';
        VARIABLE TD_LDQS1_CK5      : VitalTimingDataType;

        VARIABLE Tviol_LDQS1_CK6   : X01 := '0';
        VARIABLE TD_LDQS1_CK6      : VitalTimingDataType;

        VARIABLE Tviol_UDQS_CK3    : X01 := '0';
        VARIABLE TD_UDQS_CK3       : VitalTimingDataType;

        VARIABLE Tviol_UDQS_CK4    : X01 := '0';
        VARIABLE TD_UDQS_CK4       : VitalTimingDataType;

        VARIABLE Tviol_UDQS_CK5    : X01 := '0';
        VARIABLE TD_UDQS_CK5       : VitalTimingDataType;

        VARIABLE Tviol_UDQS_CK6    : X01 := '0';
        VARIABLE TD_UDQS_CK6       : VitalTimingDataType;

        VARIABLE Tviol_UDQS1_CK3   : X01 := '0';
        VARIABLE TD_UDQS1_CK3      : VitalTimingDataType;

        VARIABLE Tviol_UDQS1_CK4   : X01 := '0';
        VARIABLE TD_UDQS1_CK4      : VitalTimingDataType;

        VARIABLE Tviol_UDQS1_CK5   : X01 := '0';
        VARIABLE TD_UDQS1_CK5      : VitalTimingDataType;

        VARIABLE Tviol_UDQS1_CK6   : X01 := '0';
        VARIABLE TD_UDQS1_CK6      : VitalTimingDataType;