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PREFACE

About This Note

This note is a supplement to the

Macintosh Developer Notes, Number 2,
Macintosh Duo System,

APDA publication number R0457LL/A. It describes the
design features of the PowerBook Duo 250 computer, which is basically a
PowerBook Duo computer with an active-matrix display and expanded hard
disk capabilities.
This note provides the hardware or software developer with the additional
information needed to design hardware and software elements for the
PowerBook Duo 250 computer. This publication assumes you are familiar with
the functionality and programming requirements for Apple Macintosh
computers. It consists of three chapters

Chapter 1, “Introduction to the PowerBook Duo 250 Computer”

Chapter 2, “Hardware Modifications”

Chapter 3, “Software Modifications”
It also contains an index.

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