Preface
Product revision status
The rn
pn
identifier indicates the revision status of the product described in this book, where:
- r
n
- Identifies the major revision of the product.
- p
n
- Identifies the minor revision or modification status of the product.
Glossary
The ARM Glossary is a list of terms used in ARM documentation, together with definitions for those terms. The ARM Glossary does not contain terms that are industry standard unless the ARM meaning differs from the generally accepted meaning.
See the ARM Glossary for more information.
Typographic conventions
- italic
- Introduces special terminology, denotes cross-references, and citations.
- bold
- Highlights interface elements, such as menu names. Denotes signal names. Also used for terms in descriptive lists, where appropriate.
- monospace
- Denotes text that you can enter at the keyboard, such as commands, file and program names, and source code.
- space
- Denotes a permitted abbreviation for a command or option. You can enter the underlined text instead of the full command or option name.
- monospace italic
- Denotes arguments to monospace text where the argument is to be replaced by a specific value.
- monospace bold
- Denotes language keywords when used outside example code.
- <and>
- Encloses replaceable terms for assembler syntax where they appear in code or code fragments. For example:
MRC p15, 0 <Rd>, <CRn>, <CRm>, <Opcode_2>
- SMALL CAPITALS
- Used in body text for a few terms that have specific technical meanings, that are defined in the ARM glossary. For example, IMPLEMENTATION DEFINED, IMPLEMENTATION SPECIFIC, UNKNOWN, and UNPREDICTABLE.
Timing diagrams
The following figure explains the components used in timing diagrams. Variations, when they occur, have clear labels. You must not assume any timing information that is not explicit in the diagrams.
Shaded bus and signal areas are undefined, so the bus or signal can assume any value within the shaded area at that time. The actual level is unimportant and does not affect normal operation.
Key to timing diagram conventions
Signals
The signal conventions are:
- Signal level
-
The level of an asserted signal depends on whether the signal is active-HIGH or active-LOW. Asserted means:
-
HIGH for active-HIGH signals.
-
LOW for active-LOW signals.
-
- Lower-case n
-
At the start or end of a signal name denotes an active-LOW signal.
Feedback
ARM welcomes feedback on this product and its documentation.
Feedback on this product
If you have any comments or suggestions about this product, contact your supplier and give:
- The product name.
- The product revision or version.
- An explanation with as much information as you can provide. Include symptoms and diagnostic procedures if appropriate.
Feedback on content
If you have comments on content then send an e-mail to errata@arm.com . Give:
- The title.
- The number .
- The page number(s) to which your comments refer.
- A concise explanation of your comments.
ARM also welcomes general suggestions for additions and improvements.