Inside the Sinclair QL

ZX Computing

David Harwood

HARWOOD'S HYPOTHESIS Shuffling over from software reviews, David Harwood is now delving into ZX's tottering book pile. HARWOOD'S HYPOTHESIS Shuffling over from software reviews, David Harwood is now delving into ZX's tottering book pile. Moving on to better and greater heights I am now positioned on the Book Page, where in each issue a critical and informative view on the current books will be presented. Purchasing a computer book is totally different to buying a games tape. Whereas many might not think twice when spending £5.95 on an Asteroids shoot-em-up type game, in order to spend £5.95 on a book, the prospective purchaser will go through much mental strain. Will the book gather dust on the shelf or will it, in no time at all, look like a book from the archive section of the local library? Once decided a purchase can be made and it is anybody's guess if the correct decision was made. Harwood's Hypothesis intends to evaluate each book carefully, so that you, the people who keep the computer business going, can make sure that your money isn't wasted. INSIDE THE SINCLAIR QL Sunshine have produced a book for those who 'want to know how their Sinclair QL ticks.' INSIDE THE SINCLAIR QL is written by Jeff Naylor and Diane Rogers and provides an introductory guide to computer hardware. The book is split into two sections. The first explains basically what a computer is, and the second strips the QL down. The basis of computing is at first given, starting off with simple circuit diagrams and progressing on to how a computer makes sounds and the idea behind the video picture (or VDU). Then a breakdown of the components of a computer is given, from the CPU to the ROM and RAM. This section was informative and fairly comprehensive but would not, I feel, appeal to the early beginner. The second section which, incidentally, is as comprehensive as the first, starts with a brief advertising blurb for the QL, showing its family tree (ie ZX80, ZX81, ZX SPECTRUM ... SINCLAIR QUANTUM LEAP) and the QL specification. The QL hardware structure is then described, along with the strip down of the Motorola 68008 microprocessor. A whole chapter is devoted to the 68008 instruction set as well as a chapter on exploring machine code on the QL. The final chapters, explaining the memory, video display and INPUT/OUTPUT methods have, perhaps been printed in the incorrect place and should have appeared at the same time as the QL hardware was described and not after the chapter on machine code. My conclusion is that this is quite an informative book, not at all intended for the beginner but someone who perhaps knows his/her BASIC, or SuperBASlC and wants to learn more about the computer. The book, retailing at £6.95, does cover the vast area of technicalities on the Sinclair QL and is well researched.