docs/wiki/geda-vams_netlister_readme.html

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  13 <h1 class="sectionedit1" id="vams_netlister_readme">VAMS netlister README</h1>
  14 <div class="level1">
  15
  16 </div>
  17 <!-- EDIT1 SECTION "VAMS netlister README" [1-36] -->
  18 <h2 class="sectionedit2" id="vams_netlister">VAMS netlister</h2>
  19 <div class="level2">
  20 <pre class="code">date: 10 october 2000
  21 gEDA: gnetlist vams mode
  22 first unrevised vams mode documentation
  23
  24
  25 Written by: Martin Lehmann
  26 -------------------------------------------------------------------------
  27
  28
  29 VHDL-AMS support for the gEDA gnetlist tool
  30 -------------------------------------------
  31
  32 CONTENT:
  33
  34    1. functionality
  35       1. ARCHITECTURE generation
  36       2. ENTITY generation
  37       3. automatisate gnetlist calls
  38
  39    2. implementation
  40       1. the vams mode of gEDA gnetlist
  41          1. scheme
  42             1. settings and new definition
  43             2. gnet-vams.scm
  44                1. routines main structure
  45             3. helpfully setting in gEDA gschem environment
  46
  47          2. new c-code
  48             1. routines
  49             2. code-adaptation
  50
  51       2. automatic generating gnetlist calls in gEDA gschem
  52          1. generated gEDA gnetlist calls
  53          2. scheme
  54             1. generate_netlist.scm
  55             2. settings
  56
  57          3. new c-code
  58             1. routines
  59             2. code-adaptation
  60
  61
  62    The purpose of our endevour, is that gEDA gnelist completly
  63    supportted VHDL-AMS (VHDL Analog and Mixed-Signal) netlist
  64    generation.
  65
  66    The VHDL-AMS netlist support mode is called vams.
  67
  68
  69    1. FUNCTIONALITY
  70
  71    gEDA gnetlist in vams mode allow it to generate a VHDL-AMS
  72    ARCHITECTURE or an ENTIY declaration. Which of both tasks is
  73    performed, dependends on the generate-mode variable. This variable
  74    is defined in the gnetlist command or will be set default.
  75
  76    If generate-mode=1 (default) gnetlist creates a netlist as an
  77    VHDL-AMS ARCHITECTURE of the current schematic. Otherwise
  78    (generate-mode=2), it creates an VHDL-AMS ENTITY declaration of the
  79    selected component (this task needs information from gEDA gschem,
  80    see below).
  81
  82    Now follows a stepwise discription of the program run in both
  83    submodes.
  84
  85    We presuppose that you are familiar with the structure of gEDA
  86    gnetlist usage (otherwise try gnetlist -help) and that you have
  87    ever seen an VHDL-AMS ARCHITECTURE with its belonging ENTITY. If
  88    you does not then the following distription will be seems very
  89    strange to you. Maybe the syntax files (syntax_entity.txt,
  90    syntax_architeture.txt) can helps you further.
  91
  92    ==================================================================
  93
  94    1.1. ARCHITECTURE GENERATION
  95
  96
  97    We suppose generate-mode is equal to 1, from this it follows that
  98    vams creates a netlist as an ARCHITECTURE (saved to
  99    &lt;value-of-toplevel-attribute-entity&gt;_arc.&lt;output-fileextension&gt;).
 100
 101
 102      ARCHITECTURE &lt;architecture-identifier&gt; OF &lt;entity-identifier&gt; IS
 103
 104    The architecture-identifier we are getting from the toplevel
 105    attribute architecture, which we have introduced. If it is not
 106    defined, we are setting architecture-identifier default
 107    (default_architecture).  The same have we doing with the
 108    entity-identifier (toplevel attribute entity, default_entity).
 109
 110
 111      {&lt;subnet-object&gt; &lt;subnet-name&gt; : subnet-kind;}
 112
 113    In the signal declaration part all subnets of the schematic will be
 114    declarated. A subnet declaration consists of an net-object, a
 115    net-name and a net-kind. All subnets are connected to various
 116    components pins. If this pins have all the same port-object and the
 117    same port-kind it is ok, but if one of them different, the net is
 118    faulty, and will be not declarated. Moreover, if the subnet-object
 119    a quantity, then it will be checked, whether the subnet consists
 120    exactly one output pin (port-mode), else the subnet is faulty too.
 121    The three net attributes (object, kind, mode) we are getting from
 122    the pin attribs, port_kind, port_object and port_mode (which we
 123    have introduced newly) of a component pin.
 124
 125
 126      BEGIN
 127
 128    Ok. it&#039;s only marks the start of the architecture body.
 129
 130
 131      {&lt;label&gt; : ENTITY &lt;entity&gt; [(&lt;architecture&gt;)]
 132             [GENERIC MAP (&lt;set generic&gt; =&gt; &lt;generic-value&gt;
 133                          {; &lt;set-generic=&gt; &lt;generic-value&gt;})]
 134             PORT MAP ( &lt;pin-name&gt; =&gt; &lt;subnet-name&gt;{; &lt;.. =&gt; ..&gt;});}
 135
 136    We only support component instantiation statements, like this
 137    above, because we generate simple VHDL-AMS netlists. The label of
 138    an instance is defined from the uref of the instanciated
 139    component. Watch out, this label must be unique,it is not checked
 140    anywhere. The entity variable is not the same as the
 141    entity-identifier, it is the value of the device attribute which on
 142    its part identifies the precompiled ENTITY of this special
 143    component. Similar is the architecture variable belonging to the
 144    instanciated components ARCHITECTURE (note: one ENTITY can have more
 145    ARCHITECTURES), hence we are getting it from the component
 146    attribute ARCHITECTURE (newly introduced).
 147
 148    All generics of the generic-list are component parameters, which
 149    are different from its default values (set in its ENTITY
 150    declaration). How can we distinguish them?  All defined generics
 151    are attached to the component and looks like :
 152
 153            &lt;attribute-name&gt;=?&lt;default-value&gt; &lt;- default, not in
 154                                                 generic-list
 155
 156    And if you want to change a parameter, you only must delete the
 157    ?-character and replace the default-value with your wanted value,
 158    like this :
 159
 160            &lt;attribute-name&gt;=&lt;new-value&gt; &lt;- element of generic list
 161
 162    If you do it this way, the new assigned value and its attribute-name
 163    will be appear in the GENERIC MAP (set-generic=attribute-name and
 164    generic-value=new-value).
 165
 166    The PORT MAP consists of all pins of a component and which nets
 167    them connected to. The pin-name is getting from the pin# attribute
 168    of the pin and the subnet-name means the value of the label
 169    attribute of a net (mostly default named), which the pin is
 170    connected to. If the pin directly wired to a PORT component (=
 171    component, which device attribute =PORT), then we assign the uref
 172    of this component to subnet-name.
 173
 174
 175      END ARCHITECTURE &lt;architecture-identifier&gt;;
 176
 177    I think, this line needs no more explanation. The
 178    architecture-identifier is the same like in the first line of
 179    ARCHITECTURE declaration. Hence, the ARCHITECTURE part ends here.
 180
 181    ==================================================================
 182
 183    1.2. ENTITY GENERATION
 184
 185
 186    Now, we suppose generate-mode is equal to 2, from this it follows
 187    that vams creates an ENTITY declaration of a component (save to
 188    &lt;component-device&gt;.vhdl). If there no component selected (empty
 189    top-attribs list) then it will be created an toplevel ENTITY of the
 190    current schematic (save to
 191    &lt;value-of-toplevel-attribute-entity&gt;.vhdl).
 192
 193
 194      LIBRARY &lt;library-identifier&gt;{,&lt;library-identifier&gt;};
 195      USE     &lt;package-identidier&gt;{,&lt;package-identifier&gt;};
 196
 197    Well, the context clause part is not very ingenious. All libraries
 198    and packages you needs for your simulation you must insert staticly
 199    (a library contents precompiled ENTITIES, ARCHITECTURES and
 200    PACKAGES, which are needed from base components [base of the
 201    hierachical netlist] of your schematic. a package contents
 202    predefined types, constants, ...).  We are searching for a better
 203    usability of this part.
 204
 205
 206      ENTITY &lt;entity-identifier&gt; IS
 207          [genric_clause]
 208          [port_clause]
 209      END ENTITY;
 210
 211    If you want generate a toplevel ENTITY of your current schematic
 212    then the entity-identifier is defined from the toplevel attribute
 213    entity of the schematic-file. Moreover, there are no generic_clause
 214    and no port_clause.
 215
 216    In case of an component based ENTITY declaration, the
 217    entity-identifier is getting from the device attribute of the
 218    selected component (this attribute is included in top-attribs list,
 219    which is defined in the automatic generated gnetlist command .. more
 220    about this, later).
 221
 222
 223      generic_clause :=
 224                GENERIC ( &lt;generic-identifier&gt; : REAL := &lt;default-value&gt;
 225                         {;&lt;generic-identifier&gt; : REAL := &lt;default-value&gt;});
 226
 227    All needed generic-identifiers and it default-values are getting
 228    from the top-attribs list. Note: all attached attributes of a
 229    component appears in the generic_clause, only special attributes,
 230    like uref, source and architecture, are taked out. The values of
 231    this attributes are taked from the top-attribs list, too, but it
 232    does not matter whether the value starts with a ?-character or not
 233    (?-character always will be deleted, if it exist in front of a
 234    value).
 235
 236
 237      port_clause :=
 238             PORT (&lt;port-kind&gt; &lt;port-identifier&gt; : [&lt;port-mode&gt;] &lt;port-type&gt;
 239                   {;&lt;port-kind&gt; &lt;port-identifier&gt; : [&lt;port-mode&gt;] &lt;port-type&gt;});
 240
 241    All variables of this clause are grabbed from the symbol of the
 242    selected component. Port-kind corresponds with the value of the
 243    port_kind attribute of the pin, which pin# attribute value is equal
 244    to port-identifier. Just as corresponds port-type with the the
 245    value of the pin attribute port_type and port-mode with the value
 246    of port_mode.
 247
 248    ===================================================================
 249
 250    1.3. AUTOMATISATING gnetlist CALLS
 251
 252    Because it is very arduous to type the whole gnetlist command,
 253    which all its parameters, per hand into the terminal, we are
 254    implement an automatisation of this process in gEDA gschem. This
 255    makes it possible to create a VHDL-AMS ARCHITECTURE or ENTITY
 256    whitout any commandline actions. The only thing you must do, is to
 257    use one of the following hotkeys:
 258
 259             &lt;g e&gt; for generating an ENTITY
 260             &lt;g n&gt; for genarating an ARCHITECTURE.
 261
 262         NOTE to &lt;g e&gt; - hotkey : If one component of the schematic
 263                                  selected then the ENTITY generation
 264                                  will be applied to this component !!
 265
 266    ===================================================================
 267
 268    2. IMPLEMENTATION
 269
 270    At this section it will be explained the basic concept of the
 271    implementation, which is splited in two sections. The first one
 272    aimed to the gnelist implementation and the second to the gschem
 273    implementation.
 274
 275
 276    2.1. THE VAMS MODE OF gEDA gnetlist
 277
 278    To realize gnetlist VHDL-AMS support, it was necessary to create
 279    new scheme and c stuff.
 280
 281
 282    2.1.1. SCHEME
 283
 284    The scheme implementation contents two parts. On one hand the new
 285    file gnet-vams.scm, which realize the VHDL-AMS-code generation, and
 286    on the other hand some settings in rc-files.
 287
 288
 289    2.1.1.1. SETTINGS AND NEW DEFINITIONS
 290
 291    The following lines insert in your gschemrc, or wherever you want,
 292    but it must be loaded at gnetlist startup.
 293
 294            - load two modules, which we needs in our new implementation.
 295
 296              (define-module (ice-9 ls) :use-module (ice-9 common-list)
 297                                        :use-module (ice-9 string-fun))
 298
 299            - load main file for VHDL-AMS support, which contents the
 300              startup procedure vams.
 301
 302              (load &quot;&lt;path_of_gnet-vams.scm&gt;/gnet-vams.scm&quot;)
 303
 304
 305    2.1.1.2. gnet-vams.scm
 306
 307    This file contents all necessary scheme-functions to generate
 308    VHDL-AMS-code. Especially, the main procedure vams, which can be
 309    execute from the gnetlist command.
 310
 311          For example :
 312
 313                 gnetlist -g vams schematic_filename.sch
 314
 315       ...
 316
 317
 318    2.1.2.1. ROUTINES MAIN STRUCTURE
 319
 320    the mainly functions structure looks like:
 321
 322    - (vams output-filename)
 323
 324      ARCHITECTURE generation
 325
 326         - (vams:write-secondary-unit architecture entity  output-port)
 327
 328             - (vams:write-architecture-declarative-part output-port)
 329                   - (vams:write-signal-declarations output-port)
 330
 331             - (vams:write-architecture-statement-part packages output-port)
 332                   - (vams:write-generic-map output-port package)
 333                   - (vams:write-port-map package output-port)
 334
 335      ENTITY declaraction
 336
 337          - (vams:write-primary-unit entity port-list generic-list output-port)
 338
 339              - (vams:write-context-clause output-port)
 340
 341              - (vams:write-generic-clause generic-list output-port)
 342                   - (vams:write-generic-list generic-list output-port)
 343
 344              - (vams:write-port-clause port-list output-port)
 345                   - (vams:write-port-list port-list output-port)
 346
 347
 348    2.1.1.3 HELPFULLY SETTING IN THE gEDA gschem ENVIRONMENT
 349
 350    This settings are not absolutly necessary, but they makes work
 351    easier.
 352
 353         - set in .gEDA/gschemrc or wherever you want, but place it
 354           right.
 355
 356                 (attribute-promotion &quot;enable&quot;)
 357                 (promote-invisible &quot;enable&quot;)
 358                 (enforce-hierarchy &quot;disabled&quot;)
 359
 360                 (attribute-name &quot;port_object&quot;)
 361                 (attribute-name &quot;port_type&quot;)
 362                 (attribute-name &quot;port_mode&quot;)
 363                 (attribute-name &quot;entity&quot;)
 364                 (attribute-name &quot;architecture&quot;)
 365
 366
 367    2.1.2. NEW C - CODE
 368
 369    To got all informations, which we needed for currently netlist
 370    generation, we must implemented two new c - functions.
 371
 372
 373    2.1.2.1 NEW ROUTINES (saved in vams_misc.c)
 374
 375
 376      SCM vams_get_package_attributes(SCM scm_uref)
 377
 378    The first function gets all attribute names (not its values) of a
 379    component. This routine requires the name a component (package),
 380    especially the uref of it, and returns a list of all attribute
 381    names which are attached to this package.
 382
 383    We needs this functionality to produce a currectly
 384    VHDL-AMS GENERIC MAP.
 385
 386
 387      char* vams_get_attribs_list
 388            (OBJECT *object, SCM *list, OBJECT **return_found)
 389
 390    It exists only for the support of the first function.
 391
 392
 393    2.1.2.2. CODE ADAPTATION
 394
 395    To place this new functions at gnetlist scheme&#039;s disposal, you must
 396    perform the following actions.
 397
 398      (1) gnetlist/src/g_register.c
 399
 400            gh_new_procedure1_0
 401                (&quot;gnetlist:vams-get-package-attributes&quot;,
 402                  vams_get_package_attributes);
 403
 404
 405      (2) gnetlist/include/prototype.h
 406
 407            SCM vams_get_package_attributes(SCM scm_uref);
 408
 409
 410      (3) edit gnetlist/src/Makefile.in or directly in Makefile
 411
 412          (if you have edited Makefile.in you must run make config of
 413          course)
 414
 415           - add &quot;vams_misc.c&quot; to gnetlist_SOURCES - variable
 416           - add &quot;vams_misc.o&quot; to gnetlist_OBJECTS - variable
 417
 418      (4) copy vams_misc.c to gEDA/gnetlist/src/
 419
 420      (5) compile your code newly
 421
 422    ===================================================================
 423
 424    2.2. AUTOMATIC GENERATING gnetlist CALLS IN gEDA gschem
 425
 426    To realize this new feature it was necessary to put more
 427    information from the schematic to the scheme world of gEDA gschem.
 428    Concretly, we needs the filename of the current schematic, because
 429    gEDA gnetlist required it, and the attached attributes of a
 430    selected component for creating an VHDL-AMS ENTITY.  Hence, the
 431    gnetlist command is mutated to an unidirectional interface between
 432    the world of gschem scheme and the world of gnetlist scheme.
 433
 434    There are three important things, which transfer through this
 435    interface:
 436
 437         (1) the source-file, which contents the complett filename
 438             (with path) of the current schematic.
 439
 440         (2) the top-attribs list, which contents all attached
 441             attributes of the selected component.
 442
 443         (3) the generate-mode, which is defined by the users actions.
 444
 445
 446    2.2.1. STRUCTURE OF gEDA gnetlist CALLS FROM COMMANDLINE OR FROM gEDA
 447           gschem.
 448
 449      typical commandline call :
 450
 451                 gnetlist [-o &lt;output-filename&gt;]
 452                          -g vams
 453                          &lt;schematic-file&gt;
 454
 455    There are nothing to explain. The top-attribs list and the
 456    generate-mode variable are default defined (&#039;() and 1).
 457
 458
 459    calls from gEDA gschem (3 possible variations) :
 460
 461
 462    Note: vhdl-path is a predefined variable, which is set in
 463          generate_netlist.scm first times. You can it simple redefine
 464          in your local gschemrc file, which is loading everytimes you
 465          starts gEDA gschem.
 466
 467
 468      (1) hot-key-stroke: - g n  (generate netlist)
 469
 470          --&gt; generates a netlist of the current schematic.
 471
 472
 473              gnetlist -o &lt;vhdl-path&gt;/&lt;target-file&gt;
 474                       -g vams
 475                       &lt;source-file&gt;
 476
 477           The source-file variable is equate to the complett
 478           path+filename of the current schematic, which we get with
 479           help of a self coded c function. If you cut out the filename
 480           of the source-file variable (source-file without path) then
 481           you are getting the target-file.generate-mode and
 482           top-attribs are default again.
 483
 484       (2) hot-key-stroke: - g e (generate-entity)
 485           and no component is selected.
 486
 487           --&gt; generates an toplevel ENTITY of the current
 488               schematic.
 489
 490
 491               gnetlist -c &lt;scheme-comm&gt;
 492                        -o &lt;vhdl-path&gt;/&lt;target-file&gt;
 493                        -g vams
 494                        &lt;source-file&gt;
 495
 496                   scheme-comm=&quot;(define top-attribs &#039;&lt;top-attribs&gt;)
 497                                (define generate-mode &#039;2)&quot;
 498
 499
 500            Source-file needs no comment, because it is the same as in
 501            (1). To get all attributes of a selected component, we are
 502            must write a new c function again. The values, which we get
 503            from this new function are saved in top-attribs. The sense
 504            of the scheme-comm command is to put top-attribs and
 505            generate-mode from the gschem to the gnetlist environment.
 506            At last, the target-file consists of the pure basefilename
 507            of the source-file and an .vhdl extention.
 508
 509        (3) hot-key-stroke: - g e (generate-entity)
 510            and only one component is selected.
 511
 512            --&gt; generates an ENTITY of the selected schematic.
 513
 514
 515                commandline is the same as in (2).
 516
 517
 518            Differences: The target-file is different, but it does not
 519            matter, because gnetlist generate an new output-filename in
 520            in this case (&lt;device-name-of-selected-component&gt;.vhdl,
 521            normally).But one fact is very important: the top-attribs
 522            variable includes all attached attributes of the selected
 523            component now.
 524
 525    2.2.2. SCHEME
 526
 527    The gnetlist command is generating from two scheme functions, which
 528    are saved in generate_netlist.scm. This functions starts if the
 529    gschem user is typing one of the specified hot-keys ([g e] starts
 530    generate-entity and [g n] starts generate-netlis). Both routines
 531    puts the whole gnetlist command together and execute it. The syntax
 532    you see above.
 533
 534
 535    2.2.2.1. generate_netlist.scm
 536
 537
 538    2.2.2.2. SETTINGS
 539
 540    If you want use the new feature then you must do some entries in one
 541    of your gEDA gschem rc-files
 542
 543      necessary defines:
 544
 545          - in system-gschemrc
 546
 547                     (&quot;g&quot; . gnetlist-keymap)
 548
 549            Edit your global-keymap and if &quot;g&quot; always defined then find
 550            out an other free hot-key-stroke.
 551
 552            Note: the documentation supports the &quot;g&quot; - key only.
 553
 554
 555          - in one of the gschem startup files
 556
 557              (define gnetlist-keymap
 558                &#039;((&quot;n&quot; . generate-netlist)
 559                  (&quot;e&quot; . generate-entity)))
 560
 561
 562      loads :
 563
 564             (load &quot;/home/fliser3/.gEDA/generate_netlist.scm&quot;)
 565
 566
 567    2.2.3. NEW C-CODE
 568
 569    The c-code makes it possible to get directly informations from the
 570    gschem tool, which is necessary for the online execution of
 571    gnetlist.
 572
 573
 574    2.2.3.1. ROUTINES
 575
 576    It exists two new c-functions. Both are put down in
 577    misc_for_gnetlist.c.
 578
 579
 580      SCM get_selected_filename(gpointer data,
 581                           guint callback_action,
 582                           GtkWidget *widget)
 583
 584    This function returns the whole filename of the current schematic,
 585    which is picked from the w_current-&gt;page_current-&gt;page_filename
 586    string.
 587
 588
 589      SCM get_selected_component_attributes(gpointer data,
 590                                       guint callback_action,
 591                                       GtkWidget *widget)
 592
 593    How the name is saying, this functions returns all attributes of
 594    the selected component. It is realized with a simple while loop
 595    over all objects of the schematic, which picked out all elements
 596    where the selected flag is set.
 597
 598
 599    2.2.3.2. CODE-ADAPTATION
 600
 601    Here are some actions you must conclude to makes the software
 602    runable.
 603
 604    (1) new lines in /gschem/src/g_register.c
 605
 606         gh_new_procedure0_0 (&quot;get-selected-filename&quot;,g_get_selected_filename);
 607
 608
 609    (2) new lines in /gschem/include/prototype.h
 610
 611         SCM g_get_selected_filename();
 612
 613
 614    (3) copy the file misc_for_gnetlist.c to gschem/src
 615
 616    (4) add in file /gschem/src/Makefile.in or directly in Makefile.
 617
 618        (if you have edited Makefile.in you must run make config of
 619        course)
 620
 621         - add &quot;misc_for_gnetlist.c&quot; to gschem_SOURCES - variable
 622         - add &quot;misc_for_gnetlist.o&quot; to gschem_OBJECTS - variable
 623
 624    (5) add new lines in /gschem/src/g_key.c
 625
 626          SCM g_get_selected_filename(void)
 627          {
 628            return (get_selected_filename(window_current, 0, NULL));
 629          }
 630
 631
 632    (6) compile your changed c-code newly</pre>
 633
 634 </div>
 635 <!-- EDIT2 SECTION "VAMS netlister" [37-20220] -->
 636 <h2 class="sectionedit3" id="vams_netlister_syntax_architecture">VAMS netlister syntax architecture</h2>
 637 <div class="level2">
 638 <pre class="code">ARCHITECTURE &lt;architecture-identifier&gt; OF &lt;entity-identifier&gt; IS
 639
 640       {&lt;subnet-object&gt; &lt;subnet-name&gt; : subnet-kind;}
 641
 642 BEGIN
 643
 644   {&lt;label&gt; : ENTITY &lt;entity&gt; [(&lt;architecture&gt;)]
 645             [GENERIC MAP (&lt;set-generic&gt; =&gt; &lt;generic-value&gt;
 646                          {; &lt;set-generic=&gt; &lt;generic-value&gt;})]
 647             PORT MAP ( &lt;pin-name&gt; =&gt; &lt;subnet-name&gt;{; &lt;.. =&gt; ..&gt;});}
 648
 649 END ARCHITECTURE &lt;architecture-identifier&gt;;</pre>
 650
 651 </div>
 652 <!-- EDIT3 SECTION "VAMS netlister syntax architecture" [20221-20667] -->
 653 <h2 class="sectionedit4" id="vams_netlister_syntax_entity">VAMS netlister syntax entity</h2>
 654 <div class="level2">
 655 <pre class="code">LIBRARY &lt;library-identifier&gt;{,&lt;library-identifier&gt;};
 656 USE     &lt;package-identidier&gt;{,&lt;package-identifier&gt;};
 657
 658 ENTITY &lt;entity-identifier&gt; IS
 659    [GENERIC ( &lt;generic-identifier&gt; : REAL := &lt;default-value&gt;
 660             {;&lt;generic-identifier&gt; : REAL := &lt;default-value&gt;}); ]
 661    [PORT (&lt;port-kind&gt; &lt;port-identifier&gt; : [&lt;port-mode&gt;] &lt;port-type&gt;
 662         {;&lt;port-kind&gt; &lt;port-identifier&gt; : [&lt;port-mode&gt;] &lt;port-type&gt;});]
 663 END ENTITY;</pre>
 664
 665 </div>
 666 <!-- EDIT4 SECTION "VAMS netlister syntax entity" [20668-] --></body>
 667 </html>