Notational Conventions And Terminology - Intel 8XC196NT User Manual

Appendix C — Registers — provides a compilation of all device registers arranged alphabeti-
cally by register mnemonic. It also includes tables that list the windowed direct addresses for all
SFRs in each possible window.
Glossary — defines terms with special meaning used throughout this manual.
Index — lists key topics with page number references.
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NOTATIONAL CONVENTIONS AND TERMINOLOGY

The following notations and terminology are used throughout this manual. The Glossary defines
other terms with special meanings.
#
Addresses
Assert and Deassert
Clear and Set
Instructions
The pound symbol (#) has either of two meanings, depending on the
context. When used with a signal name, the symbol means that the
signal is active low. When used in an instruction, the symbol prefixes
an immediate value in immediate addressing mode.
In this manual, both internal and external addresses use the number
of hexadecimal digits that correspond with the number of available
address lines. For example, the highest possible internal address is
shown as FFFFFFH, while the highest possible external address is
shown as FFFFFH. When writing code, use the appropriate address
conventions for the software tool you are using. (For assembly code,
a zero must precede an alphabetic character and an "H" must follow
a hexadecimal value, so FFFFFFH must be written as 0FFFFFFH.
For 'C' code, a zero plus an "x" must precede a hexadecimal value,
so FFFFFFH must be written as 0xFFFFFF.)
The terms assert and deassert refer to the act of making a signal
active (enabled) and inactive (disabled), respectively. The active
polarity (low or high) is defined by the signal name. Active-low
signals are designated by a pound symbol (#) suffix; active-high
signals have no suffix. To assert RD# is to drive it low; to assert ALE
is to drive it high; to deassert RD# is to drive it high; to deassert ALE
is to drive it low.
The terms clear and set refer to the value of a bit or the act of giving
it a value. If a bit is clear, its value is "0"; clearing a bit gives it a "0"
value. If a bit is set, its value is "1"; setting a bit gives it a "1" value.
Instruction mnemonics are shown in upper case to avoid confusion.
You may use either upper case or lower case.
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