User's Manual
PREFACE
between 80286 and 8086 processor families reduces both the time and the cost of software
development.
The Organization of This Manual
This manual describes the 80287 Numeric Processor Extension (NPX) for the 80286 microprocessor.
The material in this manual
is
presented from the perspective of software designers, both at an appli-
cations and at a systems software level.
• Chapter One, "Overview of Numeric Processing," gives an overview of the 80287
NPX
and reviews
the concepts of numeric computation using the 80287.
• Chapter Two, "Programming Numeric Applications," provides detailed information for software
designers generating applications for systems containing an
80286 CPU with an 80287 NPX. The
80286/80287 instruction set mnemonics are explained in detail, along with a description of
programming facilities for these systems. A comparative
80287 programming example
is
given.
• Chapter Three, "System-Level Numeric Programming," provides information of interest
to
systems
software writers, including details of the
80287 architecture and operational characteristics.
• Chapter Four, "Numeric Programming Examples," provides several detailed programming examples
for the 80287, including conditional branching, the conversion between floating-point values and
their
ASCII
representations, and the calculation of several trigonometric functions. These examples
illustrate assembly-language programming
on
the 80287 NPX.
• Appendix
A,
"Machine Instruction Encoding and Decoding," gives reference information
on
the
encoding of
NPX
instructions.
• Appendix
B,
"Compatability between the 80287
NPX
and the 8087," describes the differences
between the
80287 and the 8087.
•
Appendix C, "Implementing the
IEEE
P754 Standard," gives details of the IEEE P754 Standard.
• The Glossary defines 80287 and floating-point terminology. Refer to it
as
needed.
Related Publications
To best use the material in this manual, readers should be familiar with the operation and architecture
of
80286 systems. The following manuals contain information related to the content of this supplement
and of interest to programmers of
80287 systems:
• Introduction to the 80286, order number 210308
•
ASM286
Assembly Language Reference Manual, order number 121924
• 80286 Operating System Writer's Guide, order number 121960
• 80286 Hardware Reference Manual, order number 210760
• Microprocessor and Peripheral Handbook, order number 210844
• PL/M-286 User's Guide, order number 121945
• 80287 Support Library Reference Manual, order number 122129
• 8086 Software Toolbox Manual, order number 122203 (includes information about 80287 Emulator
Software)
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