IEEE 1076 standard.VHDL language reference manual.2000
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Std 1076, 2000 Edition |
IEEE STANDARD VHDL |
concurrent assertion statements described, 9.4 elaboration of, 12.4.4 syntax, 9.4
where used, 1.1.3, Clause 9 concurrent procedure call statements
described, 9.3 syntax, 9.3 usage, 9.3
where used, 1.1.3, Clause 9
concurrent procedure call statements. See also: procedure call statements. concurrent signal assignment statements, 8.4
containing delay mechanisms, 9.5 described, 9.5
elaboration of, 12.4.4 execution of, 9.5 syntax, 9.5
where used, Clause 9
concurrent signal assignment statements. See also: conditional signal assignments, selected signal assignments, signal assignment statements.
concurrent statements described, Clause 9
elaboration of, 12.4, 12.4.4 syntax, Clause 9
where used, Clause 1, 1.1, 1.2.1, 9.1, 9.6.2 condition clauses
described, 8.1 syntax, 8.1 where used, 8.1
conditional signal assignments described, 9.5.1 syntax, 9.5.1
where used, 9.5 conditions
syntax, 8.1
where used, Clause 8, 8.1, 8.7, 8.10, 9.5.1, 9.5.2, 9.7 configuration declarations
anonymous, 12.1
as declarative regions, 10.1 described, 1.3, 1.3.2 scope of, 10.4
syntax, 1.3 usage
to control elaboration of a block statement, 12.4 to define components, 9.6
visibility of, 1.1.2 where used, 11.1
configuration items implicit, 1.3.1 syntax, 1.3, 1.3.1
configuration specifications
default entity aspect of, 5.2.2
described, 5.2, 5.2.1, 5.2.1.1, 5.2.1.2, 5.2.2 elaboration of, 12.3.2.2
implicit, 12.1 restrictions
for binding indications, 5.2.1 for others and all, 5.2
syntax, 5.2
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usage
to bind component instances to design entities, 1.3, 4.5 to define copies of blocks, 9.6
where used, 1.2.1 configurations
described, Clause 1 where used, 9.6
constant declarations described, 4.3.1.1 syntax, 4.3.1.1
where used, 1.1.2, 1.2.1, 2.2, 2.5, 4.3.1.1, 9.2 constants
deferred, 2.6, 4.3.1.1 explicitly declared, 4.3.1.1 generic, 1.1.1.1
in resolution functions, 2.4 index ranges of, 3.2.1.1 initial values of, 12.3.1.4 usage
as generate parameters, 9.7
as globally static primaries, 7.4.2 as subprogram parameters, 2.1.1.1
values of, 4.3.1.1 context clauses
described, 11.3 implicit, 14.2 syntax, 11.3
where used, Clause 11, 11.1 context items
syntax, 11.3 where used, 11.3
conversion functions
restrictions in signal associations, 4.3.2.2
D
deallocation, 3.3.2 declarations
elaboration of, Clause 12, 12.1, 12.3.1, 12.3.1.1–12.3.1.7 occurring immediately within declarative regions, 10.1 of items in a design entity, Clause 1, 1.1
overloaded, 10.3, 10.5 visibility
by selection, 10.3 direct, 10.3 hidden, 10.3 potential, 10.4
declarative parts, elaboration of, 12.3, 12.3.1, 12.3.1.1–12.3.1.7, 12.3.2, 12.3.2.1–12.3.2.3 declarative regions
described, Clause 10, 10.1, 10.2 deferred bindings, 1.3
deferred constants, 2.6 defined, 4.3.1.1
delay mechanisms described, 8.4 syntax, 8.4
where used, 8.4, 9.5
DELAYED attribute, 2.2, 4.3, 4.3.2, 14.1
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delays, 3.1.3.1 inertial, 8.4 transport, 8.4
delimiters
defined, 13.2 names of, 13.2
design entities
bindings to component instances, 1.3, 5.2.1, 5.2.1.1, 9.6.1, 9.6.2 bodies of, 1.2
declarative items, Clause 1, 1.1, Clause 5, 5.1 defining external blocks, 1.3.1
defining subcomponents of, 9.6 described, Clause 1, 1.1 interfaces of, 1.1, 4.4
library requirements, 1.1.3 ports, 1.1.1
visibility, 1.1.2 design files
syntax, Clause 11, 11.1 design hierarchies
defined by configurations, 5.2.1.1, Clause 12, 12.1 defined by design entities, Clause 12, 12.1 described, Clause 1, 1.1
elaboration
conditional or iterative, 9.7 described, 12.2
of component instances, 9.6.1, 9.6.2, 9.7 elaboration
described, Clause 12, 12.1
portability of ports and generics in root, Annex C design hierarchies. See also: blocks.
design methodologies
portability issues, Annex C reusing existing libraries, 9.6 structural design, 9.6
design units
described, Clause 11, 11.1–11.4 order of analysis, 11.4
primary
denoting, 6.3
syntax, Clause 11, 11.1 where used, Clause 11, 11.1
reported in assertion violations, 8.2 reported in report statements, 8.3 secondary
portability issues, Annex C syntax, Clause 11, 11.1 where, Clause 11, 11.1
specifications related to, Clause 5, 5.1 syntax, Clause 11, 11.1
visibility of packages, 2.5 where used, Clause 11, 11.1
designators
as a basic operation, Clause 3 described, 2.2
overloaded, 2.3.1 syntax, 2.1
where used, Clause 2, 2.1, 2.1.1.3
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digits
decimal
syntax, Clause 13, 13.1
where used, Clause 13, 13.1, 13.3.1, 13.4.1 extended
syntax, 13.4.1, 13.4.2
where used, 13.4.1, 13.4.2, 13.7
direction
of discrete subtype indications, 4.2 syntax, 3.1
where used, 3.1 disconnection specifications
default
syntax, 5.3 elaboration of, 5.3 syntax, 5.3
usage
to turn off drivers of guarded signals, 4.3.1.2 with concurrent signal assignment statements, 9.5
where used, 1.1.2, 1.2.1, 2.5 discrete ranges
bounds of, 6.5, 10.5 described, 3.2.1.1 direction of, 1.3.1, 6.5 static
described, 7.4 globally static, 7.4.2 locally static, 7.4.1
syntax, 3.2.1
where used, 1.3.1, 3.2.1, 6.5, 7.3.2, 8.9 discrete types
described, 3.1
used in case statements, 8.8
drivers
active, 12.6.1, 12.6.4 assignments to, 2.1.1.2 associated, 12.6.1 constant, 1.1.1.2 creation of, 12.6 described, 12.6.1
determined by null transactions, 2.4, 12.6.1 in kernel process, 12.6, 12.6.1
initial values of, 12.6
of guarded signals, 4.3.1.2, 5.3 disconnection of, 5.3, 12.3.2.3
of signals, 4.3.1.2 DRIVING attribute, 7.4.1, 7.4.2, 14.1
DRIVING_VALUE attribute, 7.4.1, 7.4.2, 14.1
E
elaboration
dynamic, 12.5 implementation-dependent, 12.3, 12.4 of configuration declaration, 1.3
of processes, Clause 12, 12.1
of statement parts, 12.4, 12.4.1–12.4.4
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elements associations
named, 7.3.2 positional, 7.3.2 syntax, 7.3.2 where used, 7.3.2
terminology, 3.1
entities
associations
with architectures, 1.2 with components, 5.2.1.1
overloaded, 10.5 entities. See also: named entities. entity aspect
default, 5.2.2 described, 5.2.1.1 syntax, 5.2.1.1 where used, 5.2.1
entity classes
syntax, Clause 5, 5.1 usage, 4.7
where used, 4.6, 4.7, Clause 5, 5.1 entity declarations
as declarative regions, 10.1
described, Clause 1, 1.1, 1.1.1, 1.1.1.1–1.1.1.2, 1.1.2–1.1.3 scope of, 10.2
syntax, 1.1 usage, 5.2.1.1 visibility
causing default bindings, 5.2.2, Clause 12, 12.1 where used, Clause 11, 11.1
entity declarative part, Clause 1, 1.1 described, 1.1.2
syntax, 1.1.2 entity designators
restrictions, 5.1 syntax, 5.1
where used, Clause 5, 5.1, 14.1 entity headers
described, 1.1.1, 1.1.2 syntax, 1.1.1
where used, Clause 1, 1.1 entity name lists
syntax, 5.1
where used, Clause 5, 5.1 entity names
usage, 5.2.2
where used, 1.1.3, 1.3, 5.2.1.1, 9.6 entity specifications
elaboration of, 12.3.2.1 syntax, 5.1
where used, Clause 5, 5.1 entity statement part
described, 1.1.3 syntax, 1.1.3 usage, Clause 1, 1.1
entity tags
restrictions, 5.1 syntax, 5.1
IEEE STANDARD VHDL
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LANGUAGE REFERENCE MANUAL
where used, Clause 5, 5.1 enumeration types
described, 3.1.1, 3.1.1.1 elaboration of, 12.3.1.2 predefined, 3.1.1.1
enumeration types. See also: literals—enumeration. EVENT attribute, 4.3.2, 7.4.1, 7.4.2, 14.1
exit statements described, 8.11 syntax, 8.11
where used, Clause 8 explicit ancestor. See: signals. exponents
syntax, 13.4.1, 13.4.2 where used, 13.4.1, 13.4.2
exporting data. See: files—external. expressions
as initial values of variables, 4.3.1.3 associated with signal parameters, 2.1.1.3 Boolean, Clause 8, 8.1
containing signal names, 12.3 default
for interface objects, 4.3.2, 4.3.2.2 for signal values, 4.3.1.2
defining the type of, 7.3.4 described, Clause 7, 7.1 guard, 9.1
in attribute specifications, 12.3.2.1 initializing a constant, 12.3.1.4 primaries in
described, 7.1
where used, Clause 7, 7.1 qualified, Clause 3
described, 7.3.4 syntax, 7.3.4
used as globally static primaries, 7.4.2 used as locally static primaries, 7.4.1 where used, 7.1, 7.2, 7.4
restrictions
on type, 4.3.1, 4.3.1.1
on type in case statements, 8.8 sequences in, 7.2
shift
syntax, 7.1 where used, 7.1
simple
syntax, 7.1
where used, 7.1, 7.3.2
static
definition of globally static, 7.4, 7.4.2 definition of locally static, 7.4 described, 7.4, 7.4.1, 7.4.2
in concurrent assertion statements, 9.4 where used, 1.3.1, 4.3.2
syntax, 7.1 time
usage, 8.4.1
where used, Clause 8, 8.1, 8.4.1 treatment during elaboration, 12.3
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universal
described, 7.5 used as operands, 7.3
where used, 4.3.1, 4.3.1.1, 4.3.1.2, Clause 5, 5.1, 6.4, 6.6, 7.3.4, 8.2, 8.3, 8.5, 8.8, 8.12, 9.5.2 expressions. See also: guards.
external blocks, 1.3.1
F
factors
syntax, 7.1 where used, 7.1
file declarations described, 4.3.1.4
elaboration of, 12.3.1.4 syntax, 4.3.1.4
where used, 1.1.2, 1.2.1, 2.2, 2.5, 4.3.1, 9.2 file types
described, 3.4, 3.4.1
operations implicitly declared for, 3.4.1 restrictions
on attributes, 4.4 on signals, 4.3.1.2
on subprogram parameters, 4.3.1.4, 4.3.2, 4.3.2.1 on subtype indications, 4.2, 4.3.2
usage, Clause 3
with external files, 4.3.1.4, 4.3.2 where prohibited, 3.3, 4.3.1
files
explicit, 4.3.1.4 external, 4.3.1.4 read operations, 4.3.2
used as subprogram parameters, 2.1.1.3 write operations, 4.3.2
floating point types
described, 3.1.4, 3.1.4.1 elaboration of, 12.3.1.2 portability issues, Annex C predefined, 3.1.4.1 required precision, 3.1.4 syntax, 3.1.4
FOREIGN attribute, 1.1.2, 1.1.3, 1.2, 1.2.1, 1.2.2, 2.2, 12.4, 14.2 exclusion from elaboration, 12.3
portability issues, Annex C foreign subprograms, 2.2
formal designators syntax, 4.3.2.2
where used, 4.3.2.2 formal parameters
as objects, 4.3 described, 2.1.1 scope of, 10.2 syntax, 2.1.1
type profiles, 2.3, 10.5 used as constants, 4.3.1.1 where used, Clause 2, 2.1
formal parameters. See also: subprogram specifications.
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formals
in map aspects, 5.2.1.2, 9.1 syntax, 4.3.2.2 unassociated, 5.2.1.2 usage, 4.3.2.2
where used, 4.3.2.2
formals. See also: formal parameters, generics, ports. format effectors
end of line, 13.2 syntax, 13.1
where used, Clause 13, 13.1 function calls
defining parentage of subprograms, 2.2 described, 7.3.3
evaluation of, 7.3.3 in association lists
as actuals, 4.3.2.2 as formals, 4.3.2.2
restrictions
on expanded names, 6.3 on groups, 4.7
syntax, 7.3.3
treatment during elaboration, 12.3, 12.3.1 usage
as globally static primaries, 7.4.2 as locally static primaries, 7.4.1 general description, Clause 2, 2.1
where used, 6.1, 7.2 functions
in signatures, 2.3.2 invoking execution of, 7.3.3 object classes for, 2.1.1 overloaded, 4.2
portability issues of impure, Annex C predefined
NOW, 14.1, 14.2 pure, 2.1, 2.2, 2.7, 7.4.2 resolution, 2.4, 4.2 returned values, 8.12 syntax, 2.1
usage, Clause 2, 2.1 where used, 4.3.2.2
functions. See also: return statements.
G
generate parameters as objects, 4.3
constants, 4.3.1.1, 12.4.2 usage, 4.3
as globally static primaries, 7.4.2 generate statements
as declarative regions, 10.1 defining internal blocks, 1.3.1 described, 9.7
elaboration of, 12.4.2
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labels, 1.3.1
elaboration of, 12.4.2 where used, 1.3.1
syntax, 9.7
where used, Clause 9 generation schemes
syntax, 9.7 where used, 9.7
generic clauses
elaboration of, 12.2.1 syntax, 1.1.1.1 where used, 4.5, 9.1
generic lists
defined, 1.1.1 syntax, 1.1.1, 1.1.1.1
where used, 1.1.1, 1.1.1.1 generic map aspect
default, 5.2.2 described, 5.2.1.2 syntax, 5.2.1.2 usage, 5.2.1
where used, 5.2.1, 9.1, 9.6 generic map aspects
elaboration of, 12.2.2 generics
constants, 1.1.1.1, 4.3.1.1, 12.2.1 described, 1.1.1.1
formal, 5.2.2
in binding indications, 5.2.1 in block headers, 9.1
in top-level design entity, 12.1
of unconstrained array types, 3.2.1.1 scope of, 10.2
where used, 4.3.2.2 group constituents
syntax, 4.7 where used, 4.7
group declarations described, 4.6, 4.7 syntax, 4.7 usage, 4.7
where used, 1.1.2, 1.2.1, 1.3, 2.2, 2.5, 9.2 group template declarations
described, 4.6 syntax, 4.6
where used, 1.1.2, 1.2.1, 2.2, 2.5, 2.6, 9.2 group templates, 4.6
guarded signal specifications described, 5.3 elaboration of, 12.3.2.3 syntax, 12.3.2.3
where used, 12.3.2.3 guards, 4.3.1.2, 9.1, 9.4
H
HIGH attribute, 3.1.4.1, 14.1 homographs, 10.3, 11.2
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I
identifiers, 4.2 basic
described, 13.3.1 syntax, 13.3.1 where used, 13.3.1
extended
described, 13.3.2 syntax, 13.3.2 where used, 13.3.2
of named entities, Clause 4
referenced within their own declarations, 10.3 restrictions, 13.9
scope of, 10.2
separators required between, 13.2 simple names for, 0.2.1
syntax, 13.3.1, 13.3.2 visibility rules for, 10.3–10.5 where used, 1.1, 1.2, 1.3, 11.2 with overlapping scopes, 10.3
identifiers. See also: names. IEEE Std 1164-1993, Annex D if statements
described, 8.7 syntax, 8.7 usage, 9.5.1
where used, Clause 8, 9.5, 9.5.1 IMAGE attribute, 14.1
portability issues, Annex C importing data. See: files—external. IN or INOUT ports. See: ports. incomplete type declarations, 3.3.1 index constraints
described, 3.2.1.1 elaboration of, 12.3.1.3 globally static, 7.4.2 in access types, 3.3
index ranges of array types, 3.2.1.1, 3.2.1.2, 6.5 locally static, 7.4.1
syntax, 3.2.1 usage, 7.3.6
where used, 3.2.1, 4.2 index specifications
containing discrete ranges, 1.3.1 syntax, 1.3.1
where used, 1.3.1 index subtype definitions
syntax, 3.2.1 where used, 3.2.1
index subtypes
compatibility with discrete ranges, 3.2.1.1 of shift operators, 7.2.3
instance names, syntax of, 14.1 INSTANCE_NAME attribute, 14.1 instantiated units
syntax, 9.6 where used, 9.6
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