Exploring the Apple IIGS (1987)(Gary B Little)

The purpose of this book is to show you how to develop software that takes advantage of the unique features of the GS without forcing you to sift through the thousands of pages of technical information available from Apple Computer, Inc. The major new features I will cover include the enhanced operating system (ProDOS 16), a powerful sound system, two super high-resolution color graphics display modes, and hundreds of standard subroutines, called functions, a program can use to perform various operations