The fourth, if I'm not mistaken, in the 'revealed' series by Nick Hampshire, The Commodore 64 Kernal and Hardware Revealed is, like its companions in the series, an excellent and informative book.

Not exactly what you'd call a bedtime read, the book is packed full of the kind of information that's most useful for reference purposes. The introductory chapter is entitled 'Inside The Commodore 64'. I've seen that a lot of times before, but never seen it explained in such technical detail. As well as circuit diagrams, there are descriptions of the main chips such as the 6510, 6526 and the SID and VIC chips.

Subsequent chapters deal with serial communications, the cassette unit, the user port and interrupts. If this seems a strange mix of subjects, that's because they are the main areas in which the C64's KERNAL system operates. In each chapter the functions of the hardware and software are described in full. There are disassembly listings of all the Kernal functions together with documentation on how they work.

The book is more than a collection of diagrams and disassembly listings though. The text, as well as supplementing the technical information, goes over some interesting and useful subjects. The cassette chapter includes an extensive explanation of how data is recorded, how turbo loads work, and includes two fast-load listings you can incorporate into your own programs.

The chapter on the user port shows you how to hook up a speech processor chip.

To get the most out of Kernal and Hardware Revealed it would certainly help to have a working knowledge of electronics, or at least know one end of a soldering iron from the other. However, it will still be a useful book for those who want to know their machine inside out and back to front. The book is written for the most part in a highly technical style and a fair amount of knowledge on the part of the reader is taken for granted. It's not therefore a book I'd recommend to the inexperienced.

Overall, a useful book for the experienced programmer.