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Board Level Hardware Description
1
Manual Terminology
1-10
Throughout this manual, a convention is used which precedes data and address
parameters by a character identifying the numeric format as follows:
$
dollar
%
percent
&
ampersand
For example, "12" is the decimal number twelve, and "$12" is the decimal
number eighteen. Unless otherwise specified, all address references are in
hexadecimal.
An asterisk (*) following the signal name for signals which are level
significant denotes that the signal is true or valid when the signal is low.
An asterisk (*) following the signal name for signals which are edge significant
denotes that the actions initiated by that signal occur on high to low transition.
In this manual, assertion and negation are used to specify forcing a signal to a
particular state. In particular, assertion and assert refer to a signal that is active
or true; negation and negate indicate a signal that is inactive or false. These
terms are used independently of the voltage level (high or low) that they
represent.
Data and address sizes are defined as follows:
A byte is eight bits, numbered 0 through 7, with bit 0 being the least
significant.
A word is 16 bits, numbered 0 through 15, with bit 0 being the least
significant.
A longword is 32 bits, numbered 0 through 31, with bit 0 being the least
significant.
The terms "control bit" and "status bit" are used extensively in this document.
The term control bit is used to describe a bit in a register that can be set and
cleared under software control. The term "true" is used to indicate that a bit is
in the state that enables the function it controls. The term "false" is used to
indicate that the bit is in the state that disables the function it controls. In all
tables, the terms 0 and 1 are used to describe the actual value that should be
written to the bit, or the value that it yields when read. The term status bit is
used to describe a bit in a register that reflects a specific condition. The status
bit can be read by software to determine operational or exception conditions.
specifies a hexadecimal character
specifies a binary number
specifies a decimal number
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