When the original Advanced User Guide was reviewed some four years ago in Beebug Vol. 2 No. 6, we commented that it was surely destined to become the Bible for all serious Beeb owners. We weren't wrong either. It provided the kind of detailed and in-depth information that the User Guide never did, and was an enormous success with thousands of Beeb enthusiasts.

My own copy of the Advanced User Guide looks in a sad and sorry state these days, so the release of a New Advanced User Guide at this time is most welcome. This is a revised and updated version of the original book now covering the Model B, the B+, the Master, the Master Compact and the Electron.

Within the 440 pages of this spiral-bound book, are vast amounts of detailed information covering all aspects of the hardware and software incorporated in the range of BBC micros. There are in-depth details of the Basic assembler, with specific references to both the 65CO2 and 65C12, all the FX/OSBYTE calls, implementation of paged ROM software, events and interrupts, shadow RAM, the video and serial ULAs, input/output ports and interfacing, using the Tube, the Master CMOS RAM and real-time clock, programming the 1770 disc controller, and much much more.

To supplement this information, there are several listings of example programs that in themselves provide useful utilities. These include a printer buffer program, and one for reading IBM PC format discs using any BBC computer that has a 1770 disc controller.

Not only has additional information been added in this new release of the Advanced User Guide, but the guide has also been re-organised, making reference to particular topics that much easier.

The New Advanced User Guide like its predecessor, is not a book for the beginner or casual user of the Beeb. It is aimed at the programmer or serious user who requires the kind of information not available from the User Guides supplied by Acorn for the various machines. You may well ask, however, if the Master owner who already has the Master Reference manuals will find enough new information in this book to justify its purchase. The answer must be a definite yes. Although this book contains information that may already be found in the Master manuals, there is a great deal here that you will not find in Acorn's offerings.

I for one am delighted at the release of this book. I have found the original over the last four years to be invaluable, and the dilapidated condition of my own copy is testimony to the use and attention it has received. This new book will take its place on my bookshelf and continue to be my main source of reference whenever I am urgently seeking that vital piece of information about the software or hardware of my machine.