IBM Personal System/2 50 Technical Reference page 3

Preface
The Technical Reference library is intended for those who develop
hardware and software products for IBM Personal Computers and
IBM Personal System/2. Users should understand computer
architecture and programming concepts.
This technical reference provides hardware and software interface
information for the IBM Personal System/2 Model 50 and should be
used with the following publications:
IBM Personal Systeml2 Hardware Interface Technical Reference
IBM Personal Systeml2 and Personal Computer BIOS Interface
Technical Reference
This manual consists of the following sections:
Section 1, "System Overview," describes the system, features
and specifications.
Section 2, "Programmable Option Select," describes registers
used for configuration.
Section 3, "System Board," describes the system specific
hardware implementations.
Warning:
The term "Reserved" describes certain signals, bits, and
registers that should not be changed. Use of reserved areas can
cause compatibility problems, loss of data, or permanent damage to
the hardware. When the contents of a register are changed, the state
of the reserved bits must be preserved. When possible, read the
register first and change only the bits that must be changed.
For information about components or devices not described in this
manual, refer to the Hardware Interface Technical Reference.
Information about diskette drives, fixed disk drives, adapters, and
external options are in separate option technical references.
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