INTRODUCTION
Conventions
If there is a conflict between text and tables, the table shall be accepted as being correct.
Key Words
The names of abbreviations, commands, fields and acronyms used as signal names are in all uppercase type (e.g., IDENTIFY DRIVE). Fields containing only one bit are usually referred to as the “name” bit instead of the “name” field.
Names of drive registers begin with a capital letter (e.g., Cylinder High register).
Numbering
Numbers that are not followed by a lowercase “b” or “h” are decimal values. Numbers that are followed by a lowercase “b” (e.g., 01b) are binary values. Numbers that are followed by a lowercase “h” (e.g., 3Ah) are hexadecimal values.
Signal Conventions
Signal names are shown in all uppercase type.
All signals are either high active or low active signals. A dash character
When a signal is asserted, it means the signal is driven by an active circuit to its true state.
When a signal is negated, it means the signal is driven by an active circuit to its false state.
When a signal is released, it means the signal is not actively driven to any state. Some signals have bias circuitry that pull the signal to either a true or false state when no signal driver is actively asserting or negating the signal. These instances are noted under the description of the signal.
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