Toni Baker’s first book had taught ZX81 owners machine code from scratch. Her Spectrum edition followed at the end of 1983, and her publisher’s advertisement for it opened with “At last!”. Mastering Machine Code on Your ZX Spectrum was a 315-page book at £9.95 that, the advertisement promised, “assumes absolutely no previous knowledge of machine code whatsoever”. It started with “simple addition and subtraction” and finished with a working game of draughts.
Fast facts
- Author: Toni Baker
- Publisher: Interface Publications, London
- Published: end of 1983; advertised in December 1983 and reviewed in January 1984
- Length and price: 315 pages, £9.95
- Platform: ZX Spectrum (Z80)
- Before it: Mastering Machine Code on Your ZX81, by Baker, from the same publisher
From the ZX81 book to the Spectrum
Baker was already the Sinclair machine-code author. Her ZX81 book had been on sale since early 1982, and in the October/November 1982 issue of ZX Computing she turned “her attention to the Spectrum” in the first of a magazine series called “Mastering machine code on your Spectrum”. Over the next year and a half its parts made the Spectrum play music, put moving patterns on the screen in time to a record, and built a racing-car game over two issues. The magazine announced “the last part of Toni Baker’s superb series” in February 1984, a couple of months after the book came out.
The book itself was an update of the ZX81 one. John Gilbert, reviewing it for Sinclair User in January 1984, pointed out that “former owners of ZX-81s may notice that the book is an update on Interface’s ZX-81 machine code book”. The Spectrum edition was longer, with extended chapters on printing characters to the screen and on the Spectrum’s own features. “There the differences end,” he wrote. Most of the worked examples were the ones ZX81 readers knew, among them a “graffiti” program that displayed the character set and three chapters that built up the draughts game.
What was in it
Interface’s advertisement gave the shape of the course. It began with arithmetic and moved on to the speed that BASIC could not offer: “real time graphics games like BREAKOUT”, music “in real time (impossible in BASIC)” and high-resolution plotting “faster than you would have believed possible”, before the full draughts program.
Gilbert singled out one part. A long chapter gave “a dictionary of all the instructions you can give to the Z-80 processor”, which he thought turned the book into “a useful reference guide which should be of use to all beginners”, though of “little use to advanced programmers”. Appendices gave hexadecimal-to-decimal conversion tables and a list of the system variables. His one complaint was the printing: one assembly listing had been produced on a Sinclair ZX Printer, and among the typeset listings it “sticks out like a sore thumb”, and was hard to read in places.
For beginners he preferred another book. Reviewing Baker’s alongside Interface’s Spectrum Machine Code Made Easy, Volume One, by James Walsh, he found that most of what Baker covered was in Walsh’s book too, and thought Walsh’s “better as it is easier to read”.
Baker promoted it herself, with some humour. In the first issue of Your Spectrum, in January 1984, her article on scrolling the screen began with a BASIC program “adapted from a program out of Mastering Machine Code On Your ZX Spectrum (written by some looney not a million miles from these pages — plug! — and published by Interface)”.
One of a series
Interface used the same title for other machines, with other authors. Mark Greenshields wrote Mastering Machine Code on your Commodore 64 (first printed May 1984), and Clive Gifford and Scott Vincent the Amstrad CPC464/664/6128 volume (March 1986). By then the publisher had moved from Earls Court Road to Kensington High Street.
The Spectrum book stayed on sale for years. In 1987 Interface was offering it to Your Computer readers as “this acclaimed book”, for “the Spectrum and Spectrum +”, at a special price of £5.00 plus 55p postage, in the same advertisement as the Commodore 64 and Amstrad editions.
Sources
- Your Computer, February 1982: mail-order book list (the ZX81 book).
- Your Computer, December 1983, p. 190: Interface Publications advertisement, 44-46 Earls Court Road (“At last!”, 315 pages, £9.95, the contents, BREAKOUT, music, draughts).
- Sinclair User issue 22, January 1984, p. 129: John Gilbert, “Computer facts are made easy for beginners” (review); p. 108, Interface advertisement (315 pages, £9.95).
- ZX Computing, October/November 1982, p. 93; April/May 1983, p. 118; June/July 1983, p. 91; December 1983/January 1984, p. 120; February/March 1984, p. 44: Toni Baker’s “Mastering machine code on your Spectrum” series.
- Your Spectrum issue 1, January 1984, p. 28: Toni Baker’s scrolling article and her plug for the book.
- Your Computer, April and July 1987 (p. 71 and p. 58): Interface readers’ offers, 9-11 Kensington High Street.
- Mark Greenshields, Mastering Machine Code on your Commodore 64 (Interface Publications, 1984), imprint page.
- Clive Gifford and Scott Vincent, Mastering Machine Code on your Amstrad CPC464/664/6128 (Interface Publications, 1986), imprint page.