---------------------------------------------------------------------------------- File Name: ad7395.vhd---------------------------------------------------------------------------------- Copyright (C) 2003 Free Model Foundry; http://www.FreeModelFoundry.com---- This program is free software; you can redistribute it and/or modify-- it under the terms of the GNU General Public License version 2 as-- published by the Free Software Foundation.---- MODIFICATION HISTORY:---- version: | author:   | mod date: | changes made:--  V1.0    M.Radmanovic  03 Jul 25   Initial release---- This model must be compiled without VITAL compliance checking---------------------------------------------------------------------------------- PART DESCRIPTION:---- Library:    CONVERTER_VHDL-- Technology: CMOS-- Part:       AD7395-- Description: Dual, Serial Input 10-Bit DAC---- Known deficiencies: When SHDNNeg = '0' analog outputs should (but do not)-- go high impedance.--------------------------------------------------------------------------------LIBRARY IEEE;   USE IEEE.std_logic_1164.ALL;                USE IEEE.VITAL_timing.ALL;                USE IEEE.VITAL_primitives.ALL;LIBRARY FMF;    USE FMF.gen_utils.ALL;                USE FMF.conversions.ALL;---------------------------------------------------------------------------------- ENTITY DECLARATION--------------------------------------------------------------------------------ENTITY ad7395 IS    GENERIC (        -- tipd delays: interconnect path delays        tipd_SDI                    : VitalDelayType01 := VitalZeroDelay01;        tipd_LDANeg                 : VitalDelayType01 := VitalZeroDelay01;        tipd_LDBNeg                 : VitalDelayType01 := VitalZeroDelay01;        tipd_CLK                    : VitalDelayType01 := VitalZeroDelay01;        tipd_CSNeg                  : VitalDelayType01 := VitalZeroDelay01;        tipd_RSNeg                  : VitalDelayType01 := VitalZeroDelay01;        tipd_MSB                    : VitalDelayType01 := VitalZeroDelay01;        tipd_SHDNNeg                : VitalDelayType01 := VitalZeroDelay01;        -- tpd delays        -- tsetup values: setup times        tsetup_SDI_CLK              : VitalDelayType := UnitDelay;        tsetup_LDANeg_CLK           : VitalDelayType := UnitDelay;        -- thold values: hold times        thold_SDI_CLK               : VitalDelayType := UnitDelay;        thold_LDANeg_CLK            : VitalDelayType := UnitDelay;        -- tpw values: pulse widths        tpw_CLK_posedge             : VitalDelayType := UnitDelay;        tpw_CLK_negedge             : VitalDelayType := UnitDelay;        tpw_LDANeg_negedge          : VitalDelayType := UnitDelay;        tpw_RSNeg_negedge           : VitalDelayType := UnitDelay;         -- analog generics: value of Vref input In Volts        Vref                : real := 2.5;        -- generic control parameters        InstancePath        : STRING  := DefaultInstancePath;        TimingChecksOn      : BOOLEAN := DefaultTimingChecks;        MsgOn               : BOOLEAN := DefaultMsgOn;        XOn                 : BOOLEAN := DefaultXon;        -- For FMF SDF technology file usage        TimingModel         : STRING  := DefaultTimingModel    );    PORT (        SDI             : IN    std_ulogic := 'U';        LDANeg          : IN    std_ulogic := 'U';        LDBNeg          : IN    std_ulogic := 'U';        OUTA            : OUT   real := 0.0;        OUTB            : OUT   real := 0.0;        CLK             : IN    std_ulogic := 'U';        CSNeg           : IN    std_ulogic := 'U';        RSNeg           : IN    std_ulogic := 'U';        MSB             : IN    std_ulogic := 'U';        SHDNNeg         : IN    std_ulogic := 'U'    );    ATTRIBUTE VITAL_LEVEL0 of ad7395 : ENTITY IS TRUE;END ad7395;---------------------------------------------------------------------------------- ARCHITECTURE DECLARATION--------------------------------------------------------------------------------ARCHITECTURE vhdl_behavioral of ad7395 IS    ATTRIBUTE VITAL_LEVEL0 of vhdl_behavioral : ARCHITECTURE IS TRUE;    CONSTANT partID             : STRING  := "ad7395";    CONSTANT resolution         : INTEGER := 10;    SUBTYPE dacval_type IS   NATURAL RANGE 0 TO (2**resolution-1);    SIGNAL SDI_ipd              : std_ulogic := 'U';    SIGNAL LDANeg_ipd           : std_ulogic := 'U';    SIGNAL LDBNeg_ipd           : std_ulogic := 'U';    SIGNAL CLK_ipd              : std_ulogic := 'U';    SIGNAL CSNeg_ipd            : std_ulogic := 'U';    SIGNAL RSNeg_ipd            : std_ulogic := 'U';    SIGNAL MSB_ipd              : std_ulogic := 'U';    SIGNAL SHDNNeg_ipd          : std_ulogic := 'U';    SIGNAL UPDATEA              : std_ulogic := '0';    SIGNAL UPDATEB              : std_ulogic := '0';    SIGNAL dacvalA              : dacval_type;    SIGNAL dacvalB              : dacval_type;BEGIN    ----------------------------------------------------------------------------    -- Wire Delays    ----------------------------------------------------------------------------    WireDelay : BLOCK    BEGIN        w_1  : VitalWireDelay (SDI_ipd, SDI, tipd_SDI);        w_2  : VitalWireDelay (LDANeg_ipd, LDANeg, tipd_LDANeg);        w_3  : VitalWireDelay (LDBNeg_ipd, LDBNeg, tipd_LDBNeg);        w_6  : VitalWireDelay (CLK_ipd, CLK, tipd_CLK);        w_7  : VitalWireDelay (CSNeg_ipd, CSNeg, tipd_CSNeg);        w_8  : VitalWireDelay (RSNeg_ipd, RSNeg, tipd_RSNeg);        w_9  : VitalWireDelay (MSB_ipd, MSB, tipd_MSB);        w_10 : VitalWireDelay (SHDNNeg_ipd, SHDNNeg, tipd_SHDNNeg);    END BLOCK;    Behavior : BLOCK        SIGNAL OUTA_zd              : real := 0.0;        SIGNAL OUTB_zd              : real := 0.0;    BEGIN    ----------------------------------------------------------------------------     -- Behavior Process    ----------------------------------------------------------------------------    digital : PROCESS (SDI_ipd, CLK_ipd, LDANeg_ipd, LDBNeg_ipd,                       CSNeg_ipd, RSNeg_ipd, MSB_ipd, SHDNNeg_ipd)    -- Timing Check Variables    VARIABLE Tviol_SDI_CLK      : X01 := '0';    VARIABLE TD_SDI_CLK         : VitalTimingDataType;    VARIABLE Tviol_LDANeg_CLK   : X01 := '0';    VARIABLE TD_LDANeg_CLK      : VitalTimingDataType;    VARIABLE Tviol_LDBNeg_CLK   : X01 := '0';    VARIABLE TD_LDBNeg_CLK      : VitalTimingDataType;    VARIABLE PD_CLK             : VitalPeriodDataType := VitalPeriodDataInit;    VARIABLE Pviol_CLK          : X01 := '0';    VARIABLE PD_LDANeg          : VitalPeriodDataType := VitalPeriodDataInit;    VARIABLE Pviol_LDANeg       : X01 := '0';    VARIABLE PD_LDBNeg          : VitalPeriodDataType := VitalPeriodDataInit;    VARIABLE Pviol_LDBNeg       : X01 := '0';    VARIABLE PD_RSNeg           : VitalPeriodDataType := VitalPeriodDataInit;    VARIABLE Pviol_RSNeg        : X01 := '0';    VARIABLE Violation          : X01 := '0';    SUBTYPE dacreg_type IS   std_logic_vector(resolution-1 DOWNTO 0);    VARIABLE inreg              : std_logic_vector(resolution-1 DOWNTO 0);    VARIABLE dacregA            : dacreg_type;    VARIABLE dacregB            : dacreg_type;    VARIABLE LDANeg_nwv         : X01;    VARIABLE LDBNeg_nwv         : X01;    VARIABLE CSNeg_nwv          : X01;    VARIABLE RSNeg_nwv          : X01;    VARIABLE MSB_nwv            : X01;    VARIABLE CLK_nwv            : X01;    VARIABLE SDI_nwv            : X01;    VARIABLE SHDNNeg_nwv        : X01;    -- Output Glitch Detection Variables    BEGIN        SDI_nwv     := to_X01(SDI_ipd);        LDANeg_nwv  := to_X01(LDANeg_ipd);        LDBNeg_nwv  := to_X01(LDBNeg_ipd);        CLK_nwv     := to_X01(CLK_ipd);        CSNeg_nwv   := to_X01(CSNeg_ipd);        RSNeg_nwv   := to_X01(RSNeg_ipd);        MSB_nwv     := to_X01(MSB_ipd);        SHDNNeg_nwv := to_X01(SHDNNeg_ipd);        ------------------------------------------------------------------------        -- Timing Check Section        ------------------------------------------------------------------------        IF (TimingChecksOn) THEN            VitalSetupHoldCheck (                TestSignal      => SDI_ipd,                TestSignalName  => "SDI",                RefSignal       => CLK_ipd,                RefSignalName   => "CLK",                SetupHigh       => tsetup_SDI_CLK,                SetupLow        => tsetup_SDI_CLK,                HoldHigh        => thold_SDI_CLK,                HoldLow         => thold_SDI_CLK,                CheckEnabled    => (RSNeg_nwv = '1' AND CSNeg_nwv = '0'),                RefTransition   => '/',                HeaderMsg       => InstancePath & partID,                TimingData      => TD_SDI_CLK,                XOn             => XOn,                MsgOn           => MsgOn,                Violation       => Tviol_SDI_CLK            );            VitalSetupHoldCheck (                TestSignal      => LDANeg_ipd,                TestSignalName  => "LDANeg",                RefSignal       => CLK_ipd,                RefSignalName   => "CLK",                SetupHigh       => tsetup_LDANeg_CLK,                SetupLow        => tsetup_LDANeg_CLK,                HoldHigh        => thold_LDANeg_CLK,                HoldLow         => thold_LDANeg_CLK,                CheckEnabled    => (RSNeg_nwv = '1' AND CSNeg_nwv = '0'),                RefTransition   => '/',                HeaderMsg       => InstancePath & partID,                TimingData      => TD_LDANeg_CLK,                XOn             => XOn,                MsgOn           => MsgOn,                Violation       => Tviol_LDANeg_CLK            );            VitalSetupHoldCheck (                TestSignal      => LDBNeg_ipd,                TestSignalName  => "LDBNeg",                RefSignal       => CLK_ipd,                RefSignalName   => "CLK",                SetupHigh       => tsetup_LDANeg_CLK,                SetupLow        => tsetup_LDANeg_CLK,                HoldHigh        => thold_LDANeg_CLK,                HoldLow         => thold_LDANeg_CLK,                CheckEnabled    => (RSNeg_nwv = '1' AND CSNeg_nwv = '0'),                RefTransition   => '/',                HeaderMsg       => InstancePath & partID,                TimingData      => TD_LDBNeg_CLK,                XOn             => XOn,                MsgOn           => MsgOn,                Violation       => Tviol_LDBNeg_CLK            );            VitalPeriodPulseCheck (                TestSignal      => CLK_ipd,                TestSignalName  => "CLK_ipd",                PulseWidthHigh  => tpw_CLK_posedge,                PulseWidthLow   => tpw_CLK_negedge,                HeaderMsg       => InstancePath & partID,                CheckEnabled    => (RSNeg_nwv = '1' AND CSNeg_nwv = '0'),                PeriodData      => PD_CLK,                XOn             => XOn,                MsgOn           => MsgOn,                Violation       => Pviol_CLK            );            VitalPeriodPulseCheck (                TestSignal      => LDANeg_ipd,                TestSignalName  => "LDANeg",                PulseWidthLow   => tpw_LDANeg_negedge,                HeaderMsg       => InstancePath & partID,                CheckEnabled    => (RSNeg_nwv = '1'),                PeriodData      => PD_LDANeg,                XOn             => XOn,                MsgOn           => MsgOn,                Violation       => Pviol_LDANeg            );            VitalPeriodPulseCheck (                TestSignal      => LDBNeg_ipd,                TestSignalName  => "LDBNeg",                PulseWidthLow   => tpw_LDANeg_negedge,                HeaderMsg       => InstancePath & partID,                CheckEnabled    => (RSNeg_nwv = '1'),                PeriodData      => PD_LDBNeg,                XOn             => XOn,                MsgOn           => MsgOn,                Violation       => Pviol_LDBNeg            );            VitalPeriodPulseCheck (                TestSignal      => RSNeg_ipd,                TestSignalName  => "RSNeg",                PulseWidthLow   => tpw_RSNeg_negedge,                HeaderMsg       => InstancePath & partID,                CheckEnabled    => TRUE,                PeriodData      => PD_RSNeg,                XOn             => XOn,                MsgOn           => MsgOn,                Violation       => Pviol_RSNeg            );            Violation := Tviol_SDI_CLK OR Tviol_LDANeg_CLK OR                         Tviol_LDBNeg_CLK OR Pviol_CLK OR Pviol_LDANeg OR                         Pviol_LDBNeg OR Pviol_RSNeg;            ASSERT Violation = '0'                REPORT InstancePath & partID & ": simulation may be" &                       " inaccurate due to timing violations"                SEVERITY Warning;        END IF;        ------------------------------------------------------------------------        -- Functionality Section        ------------------------------------------------------------------------        IF RSNeg_nwv = '0' THEN    -- reset            IF MSB_nwv = '1' THEN                dacregA := "1000000000";                dacregB := "1000000000";            ELSE                dacregA := (others => '0');                dacregB := (others => '0');            END IF;            dacvalA <= to_nat(dacregA);            dacvalB <= to_nat(dacregB);        ELSIF CSNeg_nwv = '0' AND RSNeg_nwv = '1' THEN            IF rising_edge(CLK_ipd) THEN                FOR I IN resolution-1 DOWNTO 1 LOOP                    inreg(i) := inreg(i-1);                END LOOP;                inreg(0) := SDI_nwv;                IF LDANeg_nwv = '0' OR LDBNeg_nwv = '0' THEN                    ASSERT false                    REPORT InstancePath & partID & ": do not clock in" &                        " while LDANeg or LDBNeg are logic LOW"                        SEVERITY Warning;                END IF;            END IF;        END IF;        IF RSNeg_nwv = '1' THEN            IF LDANeg_nwv = '0' THEN -- load DacA                dacregA := inreg;                dacvalA <= to_nat(dacregA);            END IF;            IF LDBNeg_nwv = '0' THEN -- load DacB                dacregB := inreg;                dacvalB <= to_nat(dacregB);            END IF;        END IF;        ------------------------------------------------------------------------        -- Path Delay Section        ------------------------------------------------------------------------    END PROCESS digital;    dacA : PROCESS (dacvalA)    BEGIN        OUTA_zd <= (REAL(dacvalA) * Vref/REAL(2**resolution));    END PROCESS dacA;    dacB : PROCESS (dacvalB)    BEGIN        OUTB_zd <= (REAL(dacvalB) * Vref/REAL(2**resolution));    END PROCESS dacB;    OUTA <= OUTA_zd WHEN to_X01(SHDNNeg_ipd) = '1' ELSE 0.0;    OUTB <= OUTB_zd WHEN to_X01(SHDNNeg_ipd) = '1' ELSE 0.0;    END BLOCK;END vhdl_behavioral;