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Leventhal's 6502 Subroutines

6502 Assembly Language Subroutines, by Lance Leventhal and Winthrop Saville, is a book all of you will want.  Specs:  550 pages, 7-1/2 by 9-1/4 inches, paperback, $12.99 from Osborne/McGraw-Hill.  I'll send you a copy for $12 plus $2 shipping (it weighs two pounds!).  Naturally, shipping will be more if you live outside the USA.

Quoting from the back cover:

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"If you want to use a specific assembly language routine, learn assembly language quickly, or improve your programming skills, 6502 Assembly Language Programming is for you.  It provides code for more than 40 common 6502 subroutines, including code conversion, array manipulation, arithmetic, bit manipulation, string processing, input/output, and interrupts.  It describes general 6502 programming methods (including a quick summary for experienced programmers), and tells how to add instructions and addressing modes [using several instructions in sequence, subroutines, or macros].  It even discusses common 6502 assembly language programming errors."
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All of the subroutines are thoroughly documented, making it easy to understand how they work, and how to use them.  The subroutines are useful in the Apple with no changes, other than those required to interface to your own programs.  Some of the subroutines even reference the Apple monitor ROMs!

The first five copies I bought were gone within three hours of their arrival, so I ordered 20 more.  Want one?
