Terminology and Conventions

This section defines the abbreviations, terminology, and other conventions used throughout this document.

Abbreviations

Binary Multiples

The abbreviations K, M, and G (kilo, mega, and giga) represent binary multiples and have the following values.

K

=

210

(1024)

M

=

220

(1,048,576)

G

=

230

(1,073,741,824)

For example:

2KB

=

2 kilobytes

= 2 × 210 bytes

4MB

=

4 megabytes

=

4

× 220 bytes

8GB

=

8 gigabytes

=

8

× 230 bytes

2K pixels

=

2 kilopixels

=

2

× 210 pixels

4M pixels

=

4 megapixels

=

4

× 220 pixels

Register Access

The abbreviations used to indicate the type of access to register fields and bits have the following definitions:

Abbreviation

Meaning

 

 

IGN

Ignore

 

Bits and fields specified are ignored on writes.

MBZ

Must Be Zero

 

Software must never place a nonzero value in bits and fields specified as

 

MBZ. A nonzero read produces an Illegal Operand exception. Also, MBZ

 

fields are reserved for future use.

RAZ

Read As Zero

 

Bits and fields return a zero when read.

RC

Read Clears

 

Bits and fields are cleared when read. Unless otherwise specified, such bits

 

cannot be written.

RES

Reserved

 

Bits and fields are reserved by Compaq and should not be used; however,

 

zeros can be written to reserved fields that cannot be masked.

RO

Read Only

 

The value may be read by software. It is written by hardware. Software write

 

operations are ignored.

RO,n

Read Only, and takes the value n at power-on reset.

 

The value may be read by software. It is written by hardware. Software write

 

operations are ignored.

Alpha 21264/EV67 Hardware Reference Manual

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Compaq 21264, EV67 specifications Terminology and Conventions, For example, Abbreviations