In its day, Level II BASIC for the TRS-80 was an excellent programming language. Its chief drawback was derived from the fact that it was an interpreted (slow) language, not a compiled (fast) language.

I was ready for this book when it came out in 1982. Programmers like me wondered if there were any way to speed things up. BASIC compilers for the TRS-80 were not yet on the market. Then came this book with its promise to make my BASIC programs run faster.

FAST BASIC overcame the limitations of Level II BASIC in two stages. Stage One is called CONTROLLED BASIC. It uses PEEK and POKE to gain control over Level II BASIC at key points in its operation. It provided greater efficiencies in device control, in particular. For example, CONTROLLED BASIC gave Level II BASIC users direct control over TRS-80 buses, ports, video display, keyboard, cassette tape, and other peripheral devices.

Stage Two is called FAST BASIC. It makes Level II BASIC faster by enhancing it with machine language routines. How much faster? Examples in this book show that arithmetic calculations will run 3 to 4 times faster and string sorts will run 1,000 times faster. This book shows how to write enhancements like these by means of only twenty machine language instructions. The machine instructions that must be learned are kept low because all of the routines already exist in the TRS-80's ROM. The instructions are easy to master because debugging is done in BASIC, not assembler.

Of course, if you plan to enhance your Level II BASIC programs with machine language, it is essential to know how to write programs in assembly language. To this end, Part Three of this book is devoted to the Z80 chip, its register set, and its instruction set.

This brings us to Part Four, FAST BASIC itself, which achieves its greatest gains by enhancing FOR-NEXT loops, string sorting, concatenating strings, and block searching. Part Four provides step-by-step instructions for turning a Level II BASIC program, first, into a SIMPLE BASIC program and, second, into a machine language enhanced FAST BASIC program.

To make their case, the Gratzers provide an example in Chapter 12 of how to speed up a search using FAST BASIC. In Level II BASIC, their TRS-80 took 5 hours and 20 minutes to perform a FIND that searched a 64K block of memory from beginning to end. In FAST BASIC, the same task was performed in 1 second!

Much help is found in the appendices to this book.

Appendix One tells about the most useful of the TRS-80's 800 or so ROM routines and how to call them: (1) math functions, (2) type conversions, (3) I/O routines, and (4) graphics.

Appendix Two contains the Z80 instruction set with emphasis on: (1) setting and resetting flags, (2) transferring 8-bit data, (3) transferring 16-bit data, (4) transferring blocks, (5) searching blocks, (6) performing 8-bit arithmetic, (7) performing logical operations, (8) performing 16-bit arithmetic, (9) doing bit manipulation, and (10) handling halts and interrupts.

Appendix Three provides two alternate listings of the Z80 instruction set. (1) An alphabetic listing is provided for those times when you want to do hand assembly of short assembly language programs. (2) A numeric listing is provided for those times when you want to do disassemblies by hand of small machine language programs.

Appendix Four deals with advanced features of binary arithmetic: (1) binary addition, (2) binary subtraction, (3) two's complement arithmetic, (4) overflow flag, (5) binary fractions, (6) single precision arithmetic, and (7) double precision arithmetic.

Appendix Five contains two hex tables: (1) a Hex Addition Table and (2) a Hex Conversion Table.

Appendix Six contains an alphabetic list of labels for calling all of the ROM routines that are referenced in the book.

Appendix Seven contains an annotated bibliography of books, devices, machine language resources, ROM references, algorithms, magazines, software sources, editors, assemblers, and debugging tools.

Appendix Eight contains complete listings of programs that are introduced in Part One of the book. For example, there is a very nice disassembler written in TRS-80 Level II BASIC by H. Lakser.

Assumptions: (1) the reader is familiar with Level II BASIC for the TRS-80 Microcomputer; (2) the reader owns and knows how to use the Radio Shack Editor Assembler.

My Chief Gripes: First, this book is printed on cheap paper which is turning brown and brittle with age. Second, this book has a cheap glue which binds the pages to the spine. If the book is opened flat, pages easily break loose from the spine. Shame on John Wiley & Sons, Inc., for stooping so low as this just to get a book to market quickly and cheaply. ( )