avr/qmk/googletest - [no description]

about summary refs log tree commit diff stats
path: root/googlemock/docs/v1_5/Documentation.md
diff options
author	Gennadiy Civil <gennadiycivil@users.noreply.github.com>	2017-08-14 16:05:27 -0700
committer	GitHub <noreply@github.com>	2017-08-14 16:05:27 -0700
commit	5ed471caec6f341018707e74e0dc41201fb59edd (patch)
tree	7d9b6428b2661baf08c8e50bbd9fa2eac6b54816 /googlemock/docs/v1_5/Documentation.md
parent	e0fc65c5fbfe4e50a0369d032e9b2811b4b7db77 (diff)
parent	08b1a1f73cec48481ec3e477e8c247e7aa534df5 (diff)
download	googletest-5ed471caec6f341018707e74e0dc41201fb59edd.tar.gz googletest-5ed471caec6f341018707e74e0dc41201fb59edd.tar.bz2 googletest-5ed471caec6f341018707e74e0dc41201fb59edd.zip
Merge pull request #1204 from gennadiycivil/master
Changing Build Status AppVeyor badge with AppVeyor ownership change
Diffstat (limited to 'googlemock/docs/v1_5/Documentation.md')
0 files changed, 0 insertions, 0 deletions
#n146'>146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202
-------------------------------------------------------------------------------
-- Title        : Standard VITAL TIMING Package
--              : $Revision$
--              :
-- Library      : This package shall be compiled into a library
--              : symbolically named IEEE.
--              :
-- Developers   : IEEE DASC Timing Working Group (TWG), PAR 1076.4
--              :
-- Purpose      : This packages defines standard types, attributes, constants,
--              : functions and procedures for use in developing ASIC models.
--              :
-- Known Errors : 
--              :
-- Note         : No declarations or definitions shall be included in,
--              : or excluded from this package. The "package declaration"
--              : defines the objects (types, subtypes, constants, functions,
--              : procedures ... etc.) that can be used by a user.  The package
--              : body shall be considered the formal definition of the
--              : semantics of this package.  Tool developers may choose to
--              : implement the package body in the most efficient manner
--              : available to them.
-- ----------------------------------------------------------------------------
--
-- ----------------------------------------------------------------------------
-- Acknowledgments:
--   This code was originally developed under the "VHDL Initiative Toward ASIC
--   Libraries" (VITAL), an industry sponsored initiative.  Technical
--   Director: William Billowitch, VHDL Technology Group; U.S. Coordinator:
--   Steve Schultz;  Steering Committee Members: Victor Berman, Cadence Design
--   Systems; Oz Levia, Synopsys Inc.; Ray Ryan, Ryan & Ryan; Herman van Beek,
--   Texas Instruments; Victor Martin, Hewlett-Packard Company.
-- ----------------------------------------------------------------------------
--
-- ----------------------------------------------------------------------------
-- Modification History :
-- ----------------------------------------------------------------------------
-- Version No:|Auth:| Mod.Date:| Changes Made:
--   v95.0 A  |     | 06/02/95 | Initial ballot draft 1995
--   v95.1    |     | 08/31/95 | #203 - Timing violations at time 0
--                               #204 - Output mapping prior to glitch detection 
--   v98.0    |TAG  | 03/27/98 | Initial ballot draft 1998
--                             | #IR225 - Negative Premptive Glitch
--                                      **Pkg_effected=VitalPathDelay,
--                                      VitalPathDelay01,VitalPathDelay01z.
--                               #IR105 - Skew timing check needed
--                                      **Pkg_effected=NONE, New code added!! 
--                               #IR248 - Allows VPD to use a default timing 
--                                        delay
--                                      **Pkg_effected=VitalPathDelay,
--                                        VitalPathDelay01,VitalPathDelay01z,
--				                 #IR250 - Corrects fastpath condition in VPD
--                                      **Pkg_effected=VitalPathDelay01,
--                                        VitalPathDelay01z,
--                               #IR252 - Corrects cancelled timing check call if
--                                        condition expires.  
--                                        **Pkg_effected=VitalSetupHoldCheck,
--                                        VitalRecoveryRemovalCheck.
--                               #IR105 - Skew timing check 
--                                        **Pkg_effected=NONE, New code added
--   v98.1    | jdc | 03/25/99 | Changed UseDefaultDelay to IgnoreDefaultDelay
--                               and set default to FALSE in VitalPathDelay()
--   v00.7    | dbb | 07/18/00 | Removed "maximum" from VitalPeriodPulse()
--                               comments


LIBRARY IEEE;
USE     IEEE.Std_Logic_1164.ALL;

PACKAGE VITAL_Timing IS
    TYPE VitalTransitionType IS ( tr01, tr10, tr0z, trz1, tr1z, trz0,
                                  tr0X, trx1, tr1x, trx0, trxz, trzx);

    SUBTYPE VitalDelayType     IS TIME;
    TYPE VitalDelayType01   IS ARRAY (VitalTransitionType   RANGE tr01 to tr10)
         OF TIME;
    TYPE VitalDelayType01Z  IS ARRAY (VitalTransitionType   RANGE tr01 to trz0)
         OF TIME;
    TYPE VitalDelayType01ZX IS ARRAY (VitalTransitionType   RANGE tr01 to trzx)
         OF TIME;

    TYPE VitalDelayArrayType     IS ARRAY (NATURAL RANGE <>) OF VitalDelayType;
    TYPE VitalDelayArrayType01   IS ARRAY (NATURAL RANGE <>) OF VitalDelayType01;
    TYPE VitalDelayArrayType01Z  IS ARRAY (NATURAL RANGE <>) OF VitalDelayType01Z;
    TYPE VitalDelayArrayType01ZX IS ARRAY (NATURAL RANGE <>) OF VitalDelayType01ZX;
    -- ----------------------------------------------------------------------
    -- **********************************************************************
    -- ----------------------------------------------------------------------

    CONSTANT VitalZeroDelay     : VitalDelayType     :=   0 ns;
    CONSTANT VitalZeroDelay01   : VitalDelayType01   := ( 0 ns, 0 ns );
    CONSTANT VitalZeroDelay01Z  : VitalDelayType01Z  := ( OTHERS => 0 ns );
    CONSTANT VitalZeroDelay01ZX : VitalDelayType01ZX := ( OTHERS => 0 ns );

    ---------------------------------------------------------------------------
    -- examples of usage:
    ---------------------------------------------------------------------------
    -- tpd_CLK_Q : VitalDelayType  := 5 ns;
    -- tpd_CLK_Q : VitalDelayType01  := (tr01 => 2 ns, tr10 => 3 ns);
    -- tpd_CLK_Q : VitalDelayType01Z := ( 1 ns, 2 ns, 3 ns, 4 ns, 5 ns, 6 ns );
    -- tpd_CLK_Q : VitalDelayArrayType(0 to 1)
    --                          := (0 => 5 ns, 1 => 6 ns);
    -- tpd_CLK_Q : VitalDelayArrayType01(0 to 1)
    --                          := (0 => (tr01 => 2 ns, tr10 => 3 ns),
    --                              1 => (tr01 => 2 ns, tr10 => 3 ns));
    -- tpd_CLK_Q : VitalDelayArrayType01Z(0 to 1)
    --                        := (0 => ( 1 ns, 2 ns, 3 ns, 4 ns, 5 ns, 6 ns ),
    --                            1 => ( 1 ns, 2 ns, 3 ns, 4 ns, 5 ns, 6 ns ));
    ---------------------------------------------------------------------------

    -- TRUE if the model is LEVEL0 | LEVEL1 compliant
    ATTRIBUTE VITAL_Level0 : BOOLEAN;
    ATTRIBUTE VITAL_Level1 : BOOLEAN;

    SUBTYPE std_logic_vector2 IS std_logic_vector(1 DOWNTO 0);
    SUBTYPE std_logic_vector3 IS std_logic_vector(2 DOWNTO 0);
    SUBTYPE std_logic_vector4 IS std_logic_vector(3 DOWNTO 0);
    SUBTYPE std_logic_vector8 IS std_logic_vector(7 DOWNTO 0);

    -- Types for strength mapping of outputs
    TYPE VitalOutputMapType  IS ARRAY ( std_ulogic ) OF std_ulogic;
    TYPE VitalResultMapType  IS ARRAY ( UX01       ) OF std_ulogic;
    TYPE VitalResultZMapType IS ARRAY ( UX01Z      ) OF std_ulogic;
    CONSTANT VitalDefaultOutputMap  : VitalOutputMapType
                                    := "UX01ZWLH-";
    CONSTANT VitalDefaultResultMap  : VitalResultMapType
                                    := ( 'U', 'X', '0', '1' );
    CONSTANT VitalDefaultResultZMap : VitalResultZMapType
                                    := ( 'U', 'X', '0', '1', 'Z' );

    -- Types for fields of VitalTimingDataType
    TYPE VitalTimeArrayT  IS ARRAY (INTEGER RANGE <>) OF TIME;
    TYPE VitalTimeArrayPT IS ACCESS VitalTimeArrayT;
    TYPE VitalBoolArrayT  IS ARRAY (INTEGER RANGE <>) OF BOOLEAN;
    TYPE VitalBoolArrayPT IS ACCESS VitalBoolArrayT;
    TYPE VitalLogicArrayPT IS ACCESS std_logic_vector;

    TYPE VitalTimingDataType IS RECORD
        NotFirstFlag : BOOLEAN;
        RefLast   : X01;
        RefTime   : TIME;
        HoldEn    : BOOLEAN;
        TestLast  : std_ulogic;
        TestTime  : TIME;
        SetupEn   : BOOLEAN;
        TestLastA : VitalLogicArrayPT;
        TestTimeA : VitalTimeArrayPT;
        HoldEnA   : VitalBoolArrayPT;
        SetupEnA  : VitalBoolArrayPT;
    END RECORD;

    FUNCTION VitalTimingDataInit RETURN VitalTimingDataType;

    -- type for internal data of VitalPeriodPulseCheck
    TYPE VitalPeriodDataType IS RECORD
        Last : X01;
        Rise : TIME;
        Fall : TIME;
        NotFirstFlag : BOOLEAN;
    END RECORD;
    CONSTANT VitalPeriodDataInit : VitalPeriodDataType 
                                 := ('X', 0 ns, 0 ns, FALSE );

    -- Type for specifying the kind of Glitch handling to use
    TYPE VitalGlitchKindType IS (OnEvent,
                                 OnDetect,
                                 VitalInertial,
                                 VitalTransport);

    TYPE VitalGlitchDataType IS
      RECORD
        SchedTime    : TIME;
        GlitchTime   : TIME;
        SchedValue   : std_ulogic;
        LastValue    : std_ulogic;
      END RECORD;
    TYPE VitalGlitchDataArrayType IS ARRAY (NATURAL RANGE <>)
         OF VitalGlitchDataType;

    -- PathTypes: for handling simple PathDelay info
    TYPE VitalPathType IS RECORD
        InputChangeTime : TIME;             -- timestamp for path input signal
        PathDelay       : VitalDelayType;   -- delay for this path
        PathCondition   : BOOLEAN;          -- path sensitize condition
    END RECORD;
    TYPE VitalPath01Type IS RECORD
        InputChangeTime : TIME;             -- timestamp for path input signal
        PathDelay       : VitalDelayType01; -- delay for this path
        PathCondition   : BOOLEAN;          -- path sensitize condition
    END RECORD;
    TYPE VitalPath01ZType IS RECORD
        InputChangeTime : TIME;             -- timestamp for path input signal
        PathDelay       : VitalDelayType01Z;-- delay for this path
        PathCondition   : BOOLEAN;          -- path sensitize condition
    END RECORD;

    -- For representing multiple paths to an output
    TYPE VitalPathArrayType    IS ARRAY (NATURAL RANGE <> ) OF VitalPathType;
    TYPE VitalPathArray01Type  IS ARRAY (NATURAL RANGE <> ) OF VitalPath01Type;
    TYPE VitalPathArray01ZType IS ARRAY (NATURAL RANGE <> ) OF VitalPath01ZType;

    TYPE VitalTableSymbolType IS (
       '/',      -- 0 -> 1                                      
       '\',      -- 1 -> 0                                      
       'P',      -- Union of '/' and '^' (any edge to 1)                     
       'N',      -- Union of '\' and 'v' (any edge to 0)                       
       'r',      -- 0 -> X                                      
       'f',      -- 1 -> X                                      
       'p',      -- Union of '/' and 'r' (any edge from 0)               
       'n',      -- Union of '\' and 'f' (any edge from 1)               
       'R',      -- Union of '^' and 'p' (any possible rising edge)      
       'F',      -- Union of 'v' and 'n' (any possible falling edge)     
       '^',      -- X -> 1                                      
       'v',      -- X -> 0                                      
       'E',      -- Union of 'v' and '^' (any edge from X)               
       'A',      -- Union of 'r' and '^' (rising edge to or from 'X')                           
       'D',      -- Union of 'f' and 'v' (falling edge to or from 'X')                          
       '*',      -- Union of 'R' and 'F' (any edge)                      
       'X',      -- Unknown level                               
       '0',      -- low level                                   
       '1',      -- high level                                  
       '-',      -- don't care                                  
       'B',      -- 0 or 1                                      
       'Z',      -- High Impedance                              
       'S'       -- steady value                                
    );

    SUBTYPE VitalEdgeSymbolType IS VitalTableSymbolType RANGE '/' TO '*';




 -- Addition of Vital Skew Type Information 
 -- March 14, 1998 

    ---------------------------------------------------------------------------
    -- Procedures and Type Definitions for Defining Skews 
    ---------------------------------------------------------------------------
    
    TYPE VitalSkewExpectedType IS (none, s1r, s1f, s2r, s2f);
   
    TYPE VitalSkewDataType IS RECORD
        ExpectedType : VitalSkewExpectedType;
        Signal1Old1 : TIME;
        Signal2Old1 : TIME;
        Signal1Old2 : TIME;
        Signal2Old2 : TIME;
    END RECORD;

    CONSTANT VitalSkewDataInit : VitalSkewDataType := ( none, 0 ns, 0 ns, 0 ns, 0 ns );


    -- ------------------------------------------------------------------------
    --
    -- Function Name:   VitalExtendToFillDelay
    --
    -- Description:     A six element array of delay values of type 
    --                  VitalDelayType01Z is returned when a 1, 2 or 6
    --                  element array is given.  This function will convert
    --                  VitalDelayType and VitalDelayType01 delay values into
    --                  a VitalDelayType01Z type following these rules:
    --
    --                  When a VitalDelayType is passed, all six transition
    --                  values are assigned the input value.  When a 
    --                  VitalDelayType01 is passed, the 01 transitions are
    --                  assigned to the 01, 0Z and Z1 transitions and the 10
    --                  transitions are assigned to 10, 1Z and Z0 transition
    --                  values.  When a VitalDelayType01Z is passed, the values
    --                  are kept as is.
    --
    --                  The function is overloaded based on input type.
    --
    --                  There is no function to fill a 12 value delay
    --                  type.
    --
    -- Arguments:         
    --
    --  IN                 Type           Description
    --                     Delay          A one, two or six delay value Vital-
    --                                    DelayType is passed and a six delay,
    --                                    VitalDelayType01Z, item is returned.        
    --                    
    --  INOUT
    --   none
    --
    --  OUT
    --   none
    --
    --  Returns              
    --   VitalDelayType01Z
    --
    -- -------------------------------------------------------------------------
    FUNCTION VitalExtendToFillDelay (
            CONSTANT Delay : IN VitalDelayType
          ) RETURN VitalDelayType01Z;
    FUNCTION VitalExtendToFillDelay (
            CONSTANT Delay : IN VitalDelayType01
          ) RETURN VitalDelayType01Z;
    FUNCTION VitalExtendToFillDelay (
            CONSTANT Delay : IN VitalDelayType01Z
          ) RETURN VitalDelayType01Z;

    -- ------------------------------------------------------------------------
    --
    -- Function Name:   VitalCalcDelay
    --
    -- Description:     This function accepts a 1, 2 or 6 value delay and 
    --                  chooses the correct delay time to delay the NewVal 
    --                  signal.  This function is overloaded based on the
    --                  delay type passed. The function returns a single value
    --                  of time.
    --
    --                  This function is provided for Level 0 models in order
    --                  to calculate the delay which should be applied 
    --                  for the passed signal. The delay selection is performed
    --                  using the OldVal and the NewVal to determine the 
    --                  transition to select.  The default value of OldVal is X.
    --
    --                  This function cannot be used in a Level 1 model since
    --                  the VitalPathDelay routines perform the delay path
    --                  selection and output driving function.
    --
    -- Arguments:         
    --
    --  IN                 Type           Description
    --                      NewVal         New value of the signal to be
    --                                     assigned   
    --                      OldVal         Previous value of the signal.
    --                                     Default value is 'X'
    --                      Delay          The delay structure from which to
    --                                     select the appropriate delay.  The
    --                                     function overload is based on the
    --                                     type of delay passed.  In the case of
    --                                     the single delay, VitalDelayType, no
    --                                     selection is performed, since there
    --                                     is only one value to choose from.
    --                                     For the other cases, the transition
    --                                     from the old value to the new value
    --                                     decide the value returned.  
    --                    
    --  INOUT
    --   none 
    --
    --  OUT
    --   none
    --
    --  Returns              
    --   Time                              The time value selected from the
    --                                     Delay INPUT is returned.
    --
    -- -------------------------------------------------------------------------
    FUNCTION VitalCalcDelay (
            CONSTANT NewVal : IN std_ulogic   := 'X';
            CONSTANT OldVal : IN std_ulogic   := 'X';
            CONSTANT Delay  : IN VitalDelayType
          ) RETURN TIME;
    FUNCTION VitalCalcDelay (
            CONSTANT NewVal : IN std_ulogic   := 'X';
            CONSTANT OldVal : IN std_ulogic   := 'X';
            CONSTANT Delay  : IN VitalDelayType01
          ) RETURN TIME;
    FUNCTION VitalCalcDelay (
            CONSTANT NewVal : IN std_ulogic   := 'X';
            CONSTANT OldVal : IN std_ulogic   := 'X';
            CONSTANT Delay  : IN VitalDelayType01Z
          ) RETURN TIME;

   -- ------------------------------------------------------------------------
    --
    -- Function Name:   VitalPathDelay
    --
    -- Description:     VitalPathDelay is the Level 1 routine used to select
    --                  the propagation delay path and schedule a new output 
    --                  value.
    --
    --                  For single and dual delay values, VitalDelayType and
    --                  VitalDelayType01 are used.  The output value is
    --                  scheduled with a calculated delay without strength
    --                  modification.  
    --
    --                  For the six delay value, VitalDelayType01Z, the output 
    --                  value is scheduled with a calculated delay.  The drive 
    --                  strength can be modified to handle weak signal strengths
    --                  to model tri-state devices, pull-ups and pull-downs as
    --                  an example.
    --
    --                  The correspondence between the delay type and the
    --                  path delay function is as follows:
    --
    --                  Delay Type                Path Type
    --
    --                  VitalDelayType            VitalPathDelay
    --                  VitalDelayType01          VitalPathDelay01
    --                  VitalDelayType01Z         VitalPathDelay01Z
    --
    --                  For each of these routines, the following capabilities
    --                  is provided:
    --     
    --                  o Transition dependent path delay selection
    --                  o User controlled glitch detection with the ability
    --                    to generate "X" on output and report the violation
    --                  o Control of the severity level for message generation
    --                  o Scheduling of the computed values on the specified
    --                    signal.
    --                  
    --                  Selection of the appropriate path delay begins with the
    --                  candidate paths.  The candidate paths are selected by
    --                  identifying the paths for which the PathCondition is 
    --                  true.  If there is a single candidate path, then that
    --                  delay is selected.  If there is more than one candidate
    --                  path, then the shortest delay is selected using 
    --                  transition dependent delay selection.  If there is no 
    --                  candidate paths, then the delay specified by the 
    --                  DefaultDelay parameter to the path delay is used.
    --                  
    --                  Once the delay is known, the output signal is then
    --                  scheduled with that delay.  In the case of 
    --                  VitalPathDelay01Z, an additional result mapping of
    --                  the output value is performed before scheduling.  The
    --                  result mapping is performed after transition dependent
    --                  delay selection but before scheduling the final output.
    --                      
    --                  In order to perform glitch detection, the user is
    --                  obligated to provide a variable of VitalGlitchDataType
    --                  for the propagation delay functions to use.  The user
    --                  cannot modify or use this information.
    --
    -- Arguments:         
    --
    --  IN             Type                   Description
    --   OutSignalName  string                 The name of the output signal
    --   OutTemp        std_logic              The new output value to be driven
    --   Paths          VitalPathArrayType     A list of paths of VitalPathArray
    --                  VitalPathArrayType01   type.  The VitalPathDelay routine
    --                  VitalPathArrayType01Z  is overloaded based on the type
    --                                         of constant passed in.  With
    --                                         VitalPathArrayType01Z, the
    --                                         resulting output strengths can be
    --                                         mapped.
    --   DefaultDelay   VitalDelayType         The default delay can be changed 
    --                  VitalDelayType01       from zero-delay to another set
    --                  VitalDelayType01Z      of values.
    --
    --   IgnoreDefaultDelay BOOLEAN            If TRUE, the default delay will
    --                                         be used when no paths are
    --                                         selected.  If false, no event
    --                                         will be scheduled if no paths are
    --                                         selected.
    --
    --   Mode           VitalGlitchKindType    The value of this constant
    --                                         selects the type of glitch
    --                                         detection.
    --                       OnEvent           Glitch on transition event
    --                     | OnDetect          Glitch immediate on detection
    --                     | VitalInertial     No glitch, use INERTIAL
    --                                         assignment
    --                     | VitalTransport    No glitch, use TRANSPORT 
    --                                         assignment
    --   XOn            BOOLEAN                Control for generation of 'X' on 
    --                                         glitch.  When TRUE, 'X's are
    --                                         scheduled for glitches, otherwise
    --                                         no are generated.             
    --   MsgOn          BOOLEAN                Control for message generation on
    --                                         glitch detect.  When TRUE,
    --                                         glitches are reported, otherwise
    --                                         they are not reported.      
    --   MsgSeverity    SEVERITY_LEVEL         The level at which the message,
    --                                         or assertion, will be reported. 
    --   IgnoreDefaultDelay BOOLEAN            Tells the VPD whether to use the
    --                                         default delay value in the absense
    --                                         of a valid delay for input conditions 3/14/98 MG
    --
    --   OutputMap      VitalOutputMapType     For VitalPathDelay01Z, the output
    --                                         can be mapped to alternate
    --                                         strengths to model tri-state 
    --                                         devices, pull-ups and pull-downs.  
    -- 
    --  INOUT
    --   GlitchData     VitalGlitchDataType    The internal data storage
    --                                         variable required to detect
    --                                         glitches.
    --
    --  OUT
    --   OutSignal      std_logic              The output signal to be driven
    --
    --  Returns              
    --   none 
    --
    -- -------------------------------------------------------------------------
    PROCEDURE VitalPathDelay (
        SIGNAL   OutSignal          : OUT   std_logic;
        VARIABLE GlitchData         : INOUT VitalGlitchDataType;
        CONSTANT OutSignalName      : IN    string;
        CONSTANT OutTemp            : IN    std_logic;
        CONSTANT Paths              : IN    VitalPathArrayType;
        CONSTANT DefaultDelay       : IN    VitalDelayType      := VitalZeroDelay;
        CONSTANT Mode               : IN    VitalGlitchKindType := OnEvent;
        CONSTANT XOn                : IN    BOOLEAN             := TRUE;
        CONSTANT MsgOn              : IN    BOOLEAN             := TRUE;
        CONSTANT MsgSeverity        : IN    SEVERITY_LEVEL      := WARNING;
        CONSTANT NegPreemptOn       : IN    BOOLEAN             := FALSE;  --IR225 3/14/98
        CONSTANT IgnoreDefaultDelay : IN    BOOLEAN             := FALSE   --IR248 3/14/98 
    );
    PROCEDURE VitalPathDelay01 (
        SIGNAL   OutSignal          : OUT   std_logic;
        VARIABLE GlitchData         : INOUT VitalGlitchDataType;
        CONSTANT OutSignalName      : IN    string;
        CONSTANT OutTemp            : IN    std_logic;
        CONSTANT Paths              : IN    VitalPathArray01Type;
        CONSTANT DefaultDelay       : IN    VitalDelayType01    := VitalZeroDelay01;
        CONSTANT Mode               : IN    VitalGlitchKindType := OnEvent;
        CONSTANT XOn                : IN    BOOLEAN             := TRUE;
        CONSTANT MsgOn              : IN    BOOLEAN             := TRUE;
        CONSTANT MsgSeverity        : IN    SEVERITY_LEVEL      := WARNING;
        CONSTANT NegPreemptOn       : IN    BOOLEAN             := FALSE;  --IR225 3/14/98
        CONSTANT IgnoreDefaultDelay : IN    BOOLEAN             := FALSE;  --IR248 3/14/98 
        CONSTANT RejectFastPath     : IN    BOOLEAN             := FALSE   --IR250
    );
    PROCEDURE VitalPathDelay01Z (
        SIGNAL   OutSignal          : OUT   std_logic;
        VARIABLE GlitchData         : INOUT VitalGlitchDataType;
        CONSTANT OutSignalName      : IN    string;
        CONSTANT OutTemp            : IN    std_logic;
        CONSTANT Paths              : IN    VitalPathArray01ZType;
        CONSTANT DefaultDelay       : IN    VitalDelayType01Z   := VitalZeroDelay01Z;
        CONSTANT Mode               : IN    VitalGlitchKindType := OnEvent;
        CONSTANT XOn                : IN    BOOLEAN             := TRUE;
        CONSTANT MsgOn              : IN    BOOLEAN             := TRUE;
        CONSTANT MsgSeverity        : IN    SEVERITY_LEVEL      := WARNING;
        CONSTANT OutputMap          : IN    VitalOutputMapType  := VitalDefaultOutputMap;
        CONSTANT NegPreemptOn       : IN    BOOLEAN             := FALSE;  --IR225 3/14/98
        CONSTANT IgnoreDefaultDelay : IN    BOOLEAN             := FALSE;  --IR248 3/14/98 
        CONSTANT RejectFastPath     : IN    BOOLEAN             := FALSE   --IR250
    );

    -- ------------------------------------------------------------------------
    --
    -- Function Name:   VitalWireDelay
    --
    -- Description:     VitalWireDelay is used to delay an input signal.
    --                  The delay is selected from the input parameter passed.
    --                  The function is useful for back annotation of actual
    --                  net delays.  
    --                  
    --                  The function is overloaded to permit passing a delay
    --                  value for twire for VitalDelayType, VitalDelayType01
    --                  and VitalDelayType01Z.  twire is a generic which can
    --                  be back annotated and must be constructed to follow
    --                  the SDF to generic mapping rules.       
    --                  
    -- Arguments:         
    --
    --  IN          Type                  Description         
    --   InSig       std_ulogic            The input signal (port) to be
    --                                     delayed.
    --   twire       VitalDelayType        The delay value for which the input 
    --               VitalDelayType01      signal should be delayed.  For Vital-
    --               VitalDelayType01Z     DelayType, the value is single value 
    --                                     passed.  For VitalDelayType01 and
    --                                     VitalDelayType01Z, the appropriate
    --                                     delay value is selected by VitalCalc-
    --                                     Delay.
    --
    --  INOUT
    --   none 
    --
    --  OUT
    --   OutSig      std_ulogic            The internal delayed signal
    --
    --  Returns              
    --   none 
    --
    -- -------------------------------------------------------------------------
    PROCEDURE VitalWireDelay (
            SIGNAL   OutSig     : OUT   std_ulogic;
            SIGNAL   InSig      : IN    std_ulogic;
            CONSTANT twire      : IN    VitalDelayType
        );

    PROCEDURE VitalWireDelay (
            SIGNAL   OutSig     : OUT   std_ulogic;
            SIGNAL   InSig      : IN    std_ulogic;
            CONSTANT twire      : IN    VitalDelayType01
        );

    PROCEDURE VitalWireDelay (
            SIGNAL   OutSig     : OUT   std_ulogic;
            SIGNAL   InSig      : IN    std_ulogic;
            CONSTANT twire      : IN    VitalDelayType01Z
        );

    -- ------------------------------------------------------------------------
    --
    -- Function Name:   VitalSignalDelay
    --
    -- Description:     The VitalSignalDelay procedure is called in a signal
    --                  delay block in the architecture to delay the 
    --                  appropriate test or reference signal in order to 
    --                  accommodate negative constraint checks.
    --
    --                  The amount of delay is of type TIME and is a constant.
    --
    -- Arguments:         
    --
    --  IN                Type            Description         
    --   InSig             std_ulogic      The signal to be delayed.
    --   dly               TIME            The amount of time the signal is
    --                                     delayed.
    --
    --  INOUT
    --   none
    --
    --  OUT
    --   OutSig            std_ulogic      The delayed signal
    --
    --  Returns              
    --   none
    --
    -- -------------------------------------------------------------------------
    PROCEDURE VitalSignalDelay (
            SIGNAL   OutSig     : OUT   std_ulogic;
            SIGNAL   InSig      : IN    std_ulogic;
            CONSTANT dly        : IN   TIME
    );

    -- ------------------------------------------------------------------------
    --
    -- Function Name:  VitalSetupHoldCheck
    --
    -- Description:    The VitalSetupHoldCheck procedure detects a setup or a 
    --                 hold violation on the input test signal with respect
    --                 to the corresponding input reference signal.  The timing 
    --                 constraints are specified through parameters 
    --                 representing the high and low values for the setup and
    --                 hold values for the setup and hold times.  This 
    --                 procedure assumes non-negative values for setup and hold 
    --                 timing constraints. 
    --
    --                 It is assumed that negative timing constraints
    --                 are handled by internally delaying the test or
    --                 reference signals.  Negative setup times result in
    --                 a delayed reference signal.  Negative hold times
    --                 result in a delayed test signal.  Furthermore, the
    --                 delays and constraints associated with these and
    --                 other signals may need to be appropriately
    --                 adjusted so that all constraint intervals overlap
    --                 the delayed reference signals and all constraint
    --                 values (with respect to the delayed signals) are
    --                 non-negative.
    --
    --                 This function is overloaded based on the input
    --                 TestSignal.  A vector and scalar form are provided.
    --                  
    -- TestSignal XXXXXXXXXXXX____________________________XXXXXXXXXXXXXXXXXXXXXX
    --            :
    --            :        -->|       error region       |<--
    --            :
    --            _______________________________
    -- RefSignal                                 \______________________________
    --            :           |                  |       |
    --            :           |               -->|       |<-- thold
    --            :        -->|     tsetup       |<--
    --
    -- Arguments:         
    --
    --  IN                 Type           Description    
    --   TestSignal         std_ulogic     Value of test signal
    --                      std_logic_vector
    --   TestSignalName     STRING         Name of test signal
    --   TestDelay          TIME           Model's internal delay associated
    --                                     with TestSignal
    --   RefSignal          std_ulogic     Value of reference signal
    --   RefSignalName      STRING         Name of reference signal
    --   RefDelay           TIME           Model's internal delay associated
    --                                     with RefSignal
    --   SetupHigh          TIME           Absolute minimum time duration before
    --                                     the transition of RefSignal for which
    --                                     transitions of TestSignal are allowed
    --                                     to proceed to the "1" state without
    --                                     causing a setup violation.      
    --   SetupLow           TIME           Absolute minimum time duration before 
    --                                     the transition of RefSignal for which
    --                                     transitions of TestSignal are allowed
    --                                     to proceed to the "0" state without
    --                                     causing a setup violation.      
    --   HoldHigh           TIME           Absolute minimum time duration after
    --                                     the transition of RefSignal for which
    --                                     transitions of TestSignal are allowed
    --                                     to proceed to the "1" state without
    --                                     causing a hold violation.      
    --   HoldLow            TIME           Absolute minimum time duration after 
    --                                     the transition of RefSignal for which
    --                                     transitions of TestSignal are allowed
    --                                     to proceed to the "0" state without
    --                                     causing a hold violation.      
    --   CheckEnabled       BOOLEAN        Check performed if TRUE.
    --   RefTransition      VitalEdgeSymbolType
    --                                     Reference edge specified. Events on
    --                                     the RefSignal which match the edge
    --                                     spec. are used as reference edges.      
    --   HeaderMsg          STRING         String that will accompany any
    --                                     assertion messages produced.
    --   XOn                BOOLEAN         If TRUE, Violation output parameter
    --                                     is set to "X". Otherwise, Violation
    --                                     is always set to "0".
    --   MsgOn              BOOLEAN        If TRUE, set and hold violation 
    --                                     message will be generated.
    --                                     Otherwise, no messages are generated,
    --                                     even upon violations.
    --   MsgSeverity        SEVERITY_LEVEL Severity level for the assertion.      
    --   EnableSetupOnTest  BOOLEAN        If FALSE at the time that the 
    --                                     TestSignal signal changes, 
    --                                     no setup check will be performed.
    --   EnableSetupOnRef   BOOLEAN        If FALSE at the time that the 
    --                                     RefSignal signal changes, 
    --                                     no setup check will be performed.
    --   EnableHoldOnRef    BOOLEAN        If FALSE at the time that the 
    --                                     RefSignal signal changes, 
    --                                     no hold check will be performed.
    --   EnableHoldOnTest   BOOLEAN        If FALSE at the time that the 
    --                                     TestSignal signal changes, 
    --                                     no hold check will be performed.
    --              
    --  INOUT
    --   TimingData         VitalTimingDataType  
    --                                     VitalSetupHoldCheck information
    --                                     storage area.  This is used
    --                                     internally to detect reference edges
    --                                     and record the time of the last edge.
    --
    --  OUT
    --   Violation   X01                   This is the violation flag returned. 
    --
    --  Returns              
    --   none    
    --
    -- -------------------------------------------------------------------------
    PROCEDURE VitalSetupHoldCheck (
            VARIABLE Violation     : OUT    X01;
            VARIABLE TimingData    : INOUT  VitalTimingDataType;
            SIGNAL   TestSignal    : IN     std_ulogic;
            CONSTANT TestSignalName: IN     STRING := "";
            CONSTANT TestDelay     : IN     TIME := 0 ns;
            SIGNAL   RefSignal     : IN     std_ulogic;
            CONSTANT RefSignalName : IN     STRING := "";
            CONSTANT RefDelay      : IN     TIME := 0 ns;
            CONSTANT SetupHigh     : IN     TIME := 0 ns;
            CONSTANT SetupLow      : IN     TIME := 0 ns;
            CONSTANT HoldHigh      : IN     TIME := 0 ns;
            CONSTANT HoldLow       : IN     TIME := 0 ns;
            CONSTANT CheckEnabled  : IN     BOOLEAN := TRUE;
            CONSTANT RefTransition : IN     VitalEdgeSymbolType;
            CONSTANT HeaderMsg     : IN     STRING := " ";
            CONSTANT XOn           : IN     BOOLEAN := TRUE;
            CONSTANT MsgOn         : IN     BOOLEAN := TRUE;
            CONSTANT MsgSeverity   : IN     SEVERITY_LEVEL := WARNING;
            CONSTANT EnableSetupOnTest : IN BOOLEAN := TRUE;	--IR252 3/23/98
	        CONSTANT EnableSetupOnRef  : IN BOOLEAN := TRUE;	--IR252 3/23/98
    	    CONSTANT EnableHoldOnRef   : IN BOOLEAN := TRUE;    --IR252 3/23/98
	        CONSTANT EnableHoldOnTest  : IN BOOLEAN := TRUE	    --IR252 3/23/98
      );

    PROCEDURE VitalSetupHoldCheck (
            VARIABLE Violation     : OUT    X01;
            VARIABLE TimingData    : INOUT  VitalTimingDataType;
            SIGNAL   TestSignal    : IN     std_logic_vector;
            CONSTANT TestSignalName: IN     STRING := "";
            CONSTANT TestDelay     : IN     TIME := 0 ns;
            SIGNAL   RefSignal     : IN     std_ulogic;
            CONSTANT RefSignalName : IN     STRING := "";
            CONSTANT RefDelay      : IN     TIME := 0 ns;
            CONSTANT SetupHigh     : IN     TIME := 0 ns;
            CONSTANT SetupLow      : IN     TIME := 0 ns;
            CONSTANT HoldHigh      : IN     TIME := 0 ns;
            CONSTANT HoldLow       : IN     TIME := 0 ns;
            CONSTANT CheckEnabled  : IN     BOOLEAN := TRUE;
            CONSTANT RefTransition : IN     VitalEdgeSymbolType;
            CONSTANT HeaderMsg     : IN     STRING := " ";
            CONSTANT XOn           : IN     BOOLEAN := TRUE;
            CONSTANT MsgOn         : IN     BOOLEAN := TRUE;
            CONSTANT MsgSeverity   : IN     SEVERITY_LEVEL := WARNING;
            CONSTANT EnableSetupOnTest : IN BOOLEAN := TRUE;	--IR252 3/23/98
	        CONSTANT EnableSetupOnRef  : IN BOOLEAN := TRUE;	--IR252 3/23/98
    	    CONSTANT EnableHoldOnRef   : IN BOOLEAN := TRUE;    --IR252 3/23/98
	        CONSTANT EnableHoldOnTest  : IN BOOLEAN := TRUE	    --IR252 3/23/98
    );


    -- ------------------------------------------------------------------------
    --
    -- Function Name:   VitalRecoveryRemovalCheck
    --
    -- Description:     The VitalRecoveryRemovalCheck detects the presence of
    --                  a recovery or removal violation on the input test 
    --                  signal with respect to the corresponding input reference
    --                  signal.  It assumes non-negative values of setup and
    --                  hold timing constraints.  The timing constraint is 
    --                  specified through parameters representing the recovery
    --                  and removal times associated with a reference edge of 
    --                  the reference signal.  A flag indicates whether a test
    --                  signal is asserted when it is high or when it is low.
    --                  
    --                  It is assumed that negative timing constraints 
    --                  are handled by internally delaying the test or 
    --                  reference signals.  Negative recovery times result in 
    --                  a delayed reference signal.  Negative removal times 
    --                  result in a delayed test signal.  Furthermore, the 
    --                  delays and constraints associated with these and
    --                  other signals may need to be appropriately
    --                  adjusted so that all constraint intervals overlap 
    --                  the delayed reference signals and all constraint
    --                  values (with respect to the delayed signals) are
    --                  non-negative.
    --                  
    -- Arguments:         
    --
    --  IN               Type             Description
    --   TestSignal       std_ulogic       Value of TestSignal.  The routine is
    --   TestSignalName   STRING           Name of TestSignal 
    --   TestDelay        TIME             Model internal delay associated with
    --                                     the TestSignal
    --   RefSignal        std_ulogic       Value of RefSignal
    --   RefSignalName    STRING           Name of RefSignal
    --   RefDelay         TIME             Model internal delay associated with
    --                                     the RefSignal
    --   Recovery         TIME             A change to an unasserted value on
    --                                     the asynchronous TestSignal must
    --                                     precede reference edge (on RefSignal)
    --                                     by at least this time.
    --   Removal          TIME             An asserted condition must be present
    --                                     on the asynchronous TestSignal for at
    --                                     least the removal time following a
    --                                     reference edge on RefSignal.
    --   ActiveLow        BOOLEAN          A flag which indicates if TestSignal
    --                                     is asserted when it is low - "0."
    --                                     FALSE indicate that TestSignal is
    --                                     asserted when it has a value "1."
    --   CheckEnabled     BOOLEAN          The check in enabled when the value
    --                                     is TRUE, otherwise the constraints 
    --                                     are not checked.
    --   RefTransition    VitalEdgeSymbolType  
    --                                     Reference edge specifier.  Events on
    --                                     RefSignal will match the edge
    --                                     specified.
    --   HeaderMsg         STRING          A header message that will accompany
    --                                     any assertion message.
    --   XOn               BOOLEAN         When TRUE, the output Violation is
    --                                     set to "X."  When FALSE, it is always 
    --                                     "0."
    --   MsgOn             BOOLEAN         When TRUE, violation messages are
    --                                     output.  When FALSE, no messages are
    --                                     generated.
    --   MsgSeverity       SEVERITY_LEVEL  Severity level of the asserted
    --                                     message.
    --   EnableRecOnTest   BOOLEAN         If FALSE at the time that the 
    --                                     TestSignal signal changes, 
    --                                     no recovery check will be performed.
    --   EnableRecOnRef    BOOLEAN         If FALSE at the time that the 
    --                                     RefSignal signal changes, 
    --                                     no recovery check will be performed.
    --   EnableRemOnRef    BOOLEAN         If FALSE at the time that the 
    --                                     RefSignal signal changes, 
    --                                     no removal check will be performed.
    --   EnableRemOnTest   BOOLEAN         If FALSE at the time that the 
    --                                     TestSignal signal changes, 
    --                                     no removal check will be performed.
    --                             
    --   INOUT
    --    TimingData       VitalTimingDataType 
    --                                     VitalRecoveryRemovalCheck information
    --                                     storage area.  This is used
    --                                     internally to detect reference edges
    --                                     and record the time of the last edge.
    --   OUT
    --    Violation        X01             This is the violation flag returned.
    --
    --   Returns              
    --           none
    --
    -- -------------------------------------------------------------------------
    PROCEDURE VitalRecoveryRemovalCheck (
            VARIABLE Violation     : OUT    X01;
            VARIABLE TimingData    : INOUT  VitalTimingDataType;
            SIGNAL   TestSignal    : IN     std_ulogic;
            CONSTANT TestSignalName: IN     STRING := "";
            CONSTANT TestDelay     : IN     TIME := 0 ns;
            SIGNAL   RefSignal     : IN     std_ulogic;
            CONSTANT RefSignalName : IN     STRING := "";
            CONSTANT RefDelay      : IN     TIME := 0 ns;
            CONSTANT Recovery      : IN     TIME := 0 ns;
            CONSTANT Removal       : IN     TIME := 0 ns;
            CONSTANT ActiveLow     : IN     BOOLEAN := TRUE;
            CONSTANT CheckEnabled  : IN     BOOLEAN := TRUE;
            CONSTANT RefTransition : IN     VitalEdgeSymbolType;
            CONSTANT HeaderMsg     : IN     STRING := " ";
            CONSTANT XOn           : IN     BOOLEAN := TRUE;
            CONSTANT MsgOn         : IN     BOOLEAN := TRUE;
            CONSTANT MsgSeverity   : IN     SEVERITY_LEVEL := WARNING;
    	    CONSTANT EnableRecOnTest : IN   BOOLEAN := TRUE;	--IR252 3/23/98
	        CONSTANT EnableRecOnRef  : IN   BOOLEAN := TRUE;	--IR252 3/23/98
	        CONSTANT EnableRemOnRef  : IN   BOOLEAN := TRUE;	--IR252 3/23/98
	        CONSTANT EnableRemOnTest : IN   BOOLEAN := TRUE		--IR252 3/23/98
    );

    -- ------------------------------------------------------------------------
    --
    -- Function Name:  VitalPeriodPulseCheck
    --
    -- Description:    VitalPeriodPulseCheck checks for minimum
    --                 periodicity and pulse width for "1" and "0" values of
    --                 the input test signal.  The timing constraint is 
    --                 specified through parameters representing the minimal
    --                 period between successive rising and falling edges of
    --                 the input test signal and the minimum pulse widths 
    --                 associated with high and low values.  
    --                 
    --                 VitalPeriodCheck's accepts rising and falling edges
    --                 from 1 and 0 as well as transitions to and from 'X.'
    --                 
    --                    _______________         __________
    --       ____________|               |_______|
    --
    --                   |<--- pw_hi --->|
    --                   |<-------- period ----->|
    --                                -->| pw_lo |<--
    --                 
    -- Arguments:
    --  IN                 Type           Description
    --    TestSignal        std_ulogic     Value of test signal  
    --    TestSignalName    STRING         Name of the test signal
    --    TestDelay         TIME           Model's internal delay associated
    --                                     with TestSignal
    --    Period            TIME           Minimum period allowed between
    --                                     consecutive rising ('P') or 
    --                                     falling ('F') transitions.
    --    PulseWidthHigh    TIME           Minimum time allowed for a high
    --                                     pulse ('1' or 'H')
    --    PulseWidthLow     TIME           Minimum time allowed for a low
    --                                     pulse ('0' or 'L')
    --    CheckEnabled      BOOLEAN        Check performed if TRUE.
    --    HeaderMsg         STRING         String that will accompany any
    --                                     assertion messages produced.   
    --    XOn               BOOLEAN        If TRUE, Violation output parameter
    --                                     is set to "X". Otherwise, Violation
    --                                     is always set to "0".
    --                                     XOnChecks is a global that allows for
    --                                     only timing checks to be turned on. 
    --    MsgOn             BOOLEAN        If TRUE, period/pulse violation
    --                                     message will be generated.
    --                                     Otherwise, no messages are generated,
    --                                     even though a violation is detected.
    --                                     MsgOnChecks allows for only timing
    --                                     check messages to be turned on. 
    --    MsgSeverity       SEVERITY_LEVEL Severity level for the assertion.
    --         
    --   INOUT
    --    PeriodData        VitalPeriodDataType 
    --                                     VitalPeriodPulseCheck information
    --                                     storage area.  This is used
    --                                     internally to detect reference edges
    --                                     and record the pulse and period
    --                                     times.
    --   OUT
    --    Violation         X01            This is the violation flag returned. 
    --
    --   Returns              
    --    none
    --
    -- ------------------------------------------------------------------------
    PROCEDURE VitalPeriodPulseCheck  (
            VARIABLE Violation      : OUT    X01;
            VARIABLE PeriodData     : INOUT  VitalPeriodDataType;
            SIGNAL   TestSignal     : IN     std_ulogic;
            CONSTANT TestSignalName : IN     STRING := "";
            CONSTANT TestDelay      : IN     TIME := 0 ns;
            CONSTANT Period         : IN     TIME := 0 ns;
            CONSTANT PulseWidthHigh : IN     TIME := 0 ns;
            CONSTANT PulseWidthLow  : IN     TIME := 0 ns;
            CONSTANT CheckEnabled   : IN     BOOLEAN := TRUE;
            CONSTANT HeaderMsg      : IN     STRING := " ";
            CONSTANT XOn           : IN     BOOLEAN := TRUE;
            CONSTANT MsgOn         : IN     BOOLEAN := TRUE;
            CONSTANT MsgSeverity   : IN     SEVERITY_LEVEL := WARNING
        );
 
    -- ------------------------------------------------------------------------
    --
    -- Function Name:  VitalInPhaseSkewCheck
    --
    -- Description:    The VitalInPhaseSkewCheck procedure detects an in-phase
    --                 skew violation between input signals Signal1 and Signal2.
    --                 This is a timer based skew check in which a
    --                 violation is detected if Signal1 and Signal2 are in
    --                 different logic states longer than the specified skew 
    --                 interval.
    --
    --                 The timing constraints are specified through parameters
    --                 representing the skew values for the different states
    --                 of Signal1 and Signal2.
    --
    --
    -- Signal2    XXXXXXXXXXXX___________________________XXXXXXXXXXXXXXXXXXXXXX
    --            :
    --            :        -->|                         |<--
    --            :      Signal2 should go low in this region
    --            :
    --
    --            ____________
    -- Signal1                \_________________________________________________
    --            :           |                         |
    --            :           |<-------- tskew -------->|
    --
    -- Arguments:
    --
    --  IN                 Type           Description
    --   Signal1            std_ulogic     Value of first signal
    --   Signal1Name        STRING         Name of first signal
    --   Signal1Delay       TIME           Model's internal delay associated
    --                                     with Signal1
    --   Signal2            std_ulogic     Value of second signal
    --   Signal2Name        STRING         Name of second signal
    --   Signal2Delay       TIME           Model's internal delay associated
    --                                     with Signal2
    --   SkewS1S2RiseRise   TIME           Absolute maximum time duration for
    --                                     which Signal2 can remain at "0"
    --                                     after Signal1 goes to the "1" state,
    --                                     without causing a skew violation.
    --   SkewS2S1RiseRise   TIME           Absolute maximum time duration for
    --                                     which Signal1 can remain at "0"
    --                                     after Signal2 goes to the "1" state,
    --                                     without causing a skew violation.
    --   SkewS1S2FallFall   TIME           Absolute maximum time duration for
    --                                     which Signal2 can remain at "1"
    --                                     after Signal1 goes to the "0" state,
    --                                     without causing a skew violation.
    --   SkewS2S1FallFall   TIME           Absolute maximum time duration for
    --                                     which Signal1 can remain at "1"
    --                                     after Signal2 goes to the "0" state,
    --                                     without causing a skew violation.
    --   CheckEnabled       BOOLEAN        Check performed if TRUE.
    --   HeaderMsg          STRING         String that will accompany any
    --                                     assertion messages produced.
    --   XOn                BOOLEAN        If TRUE, Violation output parameter
    --                                     is set to "X". Otherwise, Violation
    --                                     is always set to "0."      
    --   MsgOn              BOOLEAN        If TRUE, skew timing violation 
    --                                     messages will be generated.
    --                                     Otherwise, no messages are generated,
    --                                     even upon violations.      
    --   MsgSeverity        SEVERITY_LEVEL Severity level for the assertion.
    --

context:
space:
mode: