IEC 61691-1-1:2023

IEC 61691-1-1 ®
Edition 3.0 2023-10
™
IEEE Std 1076
INTERNATIONAL
STANDARD
Behavioural languages –
Part 1-1: VHDL Language Reference Manual
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IEC 61691-1-1 ®
Edition 3.0 2023-10
IEEE Std 1076™
INTERNATIONAL
STANDARD
Behavioural languages –
Part 1-1: VHDL Language Reference Manual
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.01, 35.060 ISBN 978-2-8322-7517-7
– i – IEEE Std 1076™-2019
Contents
1. Overview. 14
1.1 Scope. 14
1.2 Purpose. 14
1.3 Structure and terminology of this standard . 14
1.4 Word usage . 16
2. Normative references. 18
3. Design entities and configurations. 19
3.1 General . 19
3.2 Entity declarations. 19
3.3 Architecture bodies . 22
3.4 Configuration declarations. 25
4. Subprograms and packages. 32
4.1 General . 32
4.2 Subprogram declarations. 32
4.3 Subprogram bodies . 37
4.4 Subprogram instantiation declarations. 39
4.5 Subprogram overloading. 40
4.6 Resolution functions . 43
4.7 Package declarations . 44
4.8 Package bodies. 45
4.9 Package instantiation declarations . 47
4.10 Conformance rules . 48
5. Types. 49
5.1 General . 49
5.2 Scalar types . 50
5.3 Composite types. 58
5.4 Access types. 68
5.5 File types. 70
5.6 Protected types . 75
5.7 String representations. 79
5.8 Unspecified types. 81
6. Declarations . 85
6.1 General . 85
6.2 Type declarations . 86
6.3 Subtype declarations . 86
6.4 Objects . 88
6.5 Interface declarations . 96
6.6 Alias declarations. 119
6.7 Attribute declarations. 122
6.8 Component declarations.123
6.9 Group template declarations . 123
This is a copyrighted IEEE Standard. For personal or standards development use only.
Published by IEC under licence from IEEE. © 2019 IEEE. All rights reserved.
IEEE Std 1076™-2019 – ii –
6.10 Group declarations . 124
6.11 PSL clock declarations. 124
7. Specifications. 126
7.1 General . 126
7.2 Attribute specification. 126
7.3 Configuration specification.129
7.4 Disconnection specification . 135
8. Names . 138
8.1 General . 138
8.2 Simple names . 139
8.3 Selected names. 140
8.4 Indexed names. 142
8.5 Slice names . 143
8.6 Attribute names . 143
8.7 External names. 144
9. Expressions . 148
9.1 General . 148
9.2 Operators. 149
9.3 Operands . 163
9.4 Static expressions. 172
9.5 Universal expressions . 175
10. Sequential statements. 176
10.1 General . 176
10.2 Wait statement. 176
10.3 Assertion statement. 178
10.4 Report statement . 179
10.5 Signal assignment statement . 180
10.6 Variable assignment statement. 189
10.7 Procedure call statement . 191
10.8 If statement. 192
10.9 Case statement. 193
10.10 Loop statement. 195
10.11 Next statement. 196
10.12 Exit statement. 196
10.13 Return statement . 196
10.14 Null statement . 197
10.15 Sequential block statement. 197
11. Concurrent statements. 199
11.1 General .
...