Lo que quiero de unas «smart glasses»

Foto robada de Amazon de un frontal, una especie de cinta para el pelo que tiene en su parte delantera una pequeña linterna

Hace unos días se filtraron las smart glasses de Samsung, que serán las enésimas en salir al mercado. Si tenéis memoria de elefante, recordaréis que ya hemos hablado de smart glasses por aquí, porque nos gusta la tecnología más que el dulce y porque nos interesa su potencial como herramienta para mejorar la accesibilidad.

Las gafas de Samsung son, visualmente, un clon más del diseño único que parecen tener estas cosas: el aspecto de unas Rayban Wayfarer muy grandes con su cámara medianamente disimulada. Si queréis ver una comparativa de unas cuantas de las que han salido ya al mercado, este artículo de Victoria Song en The Verge tiene pinta de ser vuestro mejor recurso (y las fotos son impagables).

Y es el aspecto que precisamente no deberían tener: porque ese disimulo las hace extremadamente atractivas para el tipo de personajes que quiere usarlas para grabar situaciones poco adecuadas sin que se note. Y eso hace que, si me las pongo yo (que el concepto me llama un montón)… corra el riesgo de que alguien me tome por uno de esos individuos.

¿Cuál es el aspecto adecuado para unas smart glasses? Pues no hace falta que tengan la pinta del frontal que abre esta entrada, ni de las gafas de superguerrero de Dragonball Z de aquí abajo, pero necesitan ser obvias, y no presentar ninguna duda posible a quien pueda estar delante de su objetivo. Samsung, ya sabes. (Y tener un módulo de cámara bien obvio también os permitiría tener una mejor calidad de imagen, just saying.)

Dibujo de un personaje de Dragonball Z con sus gafas con pantalla. Las gafas cubren un solo ojo y son extremadamente obvias

Byte, abril del 86

Proseguimos con nuestro proyecto de leer la revista Byte, cuarenta años más tarde. El resto de entradas de la serie, como siempre, las encontrarás en la etiqueta Byte de obm.

Portada de la revista Byte de Abril de 1986. El tema es numbre crunching. Lo ilusta una especie de cascanueces digital (está hecho de un par de chips) que ha roto un 1 y un 0

Comenzamos con un anuncio del mítico Clipper, un lenguaje de programación pensado para reemplazar el del no menos legendario dBASE. A los programadores de una cierta edad (la última versión salió en 1997) igual se les cae una lagrimita.

Clipper gives dBASE III users more time to do more. Or less.

Clipper allows you to run all dBASEIII programs 2 to 20 times taster than they do with the standard dBASE interpreter.

That frees up extra' time you're wasting if you're running dBASE III programs without Clipper.

Extra time to think. To create. To produce. To use as you choose.

You see, Clipper is the first true compiler for dBASE III. Clipper eliminates the timeconsuming translation which the dBASE interpreter performs line after line whenever a program is run.

With Clipper, once you've debugged your source code, it's compiled into more efficient machine code. 

And Clipper compiles all your dBASE III programs. The ones you have today. The ones you'll have tomorrow. But don't wait until tomorrow to order Clipper.

Today, Clipper has already been purchased to speed up dBASE run time at 3M and Touche Ross. At Exxon and NASA. In the Harvard Physics Department. For the State of Arizona and TRW.

And that's just a few of the installations worldwide. From Greece to Venezuela to Canada to Europe.

So stop wasting time.

Call our toll-free 800 number and get Clipper.

You'll spend less time running dBASE III and more time running the rest of your life.

No os perdáis, por cierto, la sección «Ask Byte» que comienza justo antes del anuncio. Y recordad que se trata del número de abril.

Y un anuncio más. De Xerox y el PARC, su centro de investigación en el que se inventó la mitad de la informática (es probable que me quede corto), hablamos por aquí hace nada más y nada menos que catorce años. En el 86 vendían sus impresoras láser (las inventaron ellos, al fin y al cabo) y su Documenter System (haced zoom en la pantalla del ordenador de la izquierda y descubriréis un sistema que parece de una década más tarde, el Xerox 6085, heredero mítico del Xerox Star).

Anuncio de Xerox. A la izquierda vemos un ordenador con un monitor de 19 pulgadas (descomunal para la época). A la derecha vemos un sistema de impresión láser comercial que ocupara varios armarios, más ordenadores de la familia y un esquema de conexión de muchos ordenadores en una red.

Siguiendo con el tema de la autoedición, un poco más adelante nos encontramos el primer anuncio (que yo recuerde) de una implementación de TeX, que ya venía con LaTeX el sistema de autoedición que se había lanzado en el 84 y sigue adorando el mundo científico cuarenta años más tarde (yo lo descubrí a mediados de los 90, en su versión para Amiga, y no sigo porque si no, se me acabará cayendo la lagrimita).

AT LAST: Professional Typesetting Capability For PC Users

With PCTeX™, the best-selling full implementation of Professor Don Knuth's revolutionary typesetting program TeX.

FINEST Typeset Quality Printing

WIDEST Range Of Output Device Drivers:

• Epson FX, LQ • HP LaserJet*
• Toshiba • Apple LaserWriter
• Corona LP-300* • APS-5 phototypesetter
• Screen preview, with EGA or Hercules card

MOST COMPLETE Product Offering:

PC TeX (not copy protected) includes the following:

• Our specially written PCTeX Manual, which enables you to start using TeX right away.
• Custom "macro packages" that provide formats for letters, manuals, technical documents, etc.
• The LaTeX document preparation system, a fullfeatured macro package for preparing articles, books, reports, etc., and LaTeX User's Manual.
• AMSTeX developed by the Amer. Math. Society for professional mathematical typesetting.

Site licenses, volume discounts, and interfaces to PC Paintbrush, PC Palette, FancyFont and Fontrix are also available.

PRICED FROM ONLY $249.00!

(Printer drivers and interfaces additional.)

Laser printer, fonts &; software from $2995.00

Unas páginas más adelante, la revista le dedicaba unas páginas a una revisión tanto a PC TeX como a su competidor MicroTeX.

PCTeX and MicroTeX

Professional typesetting on MS-DOS machines

TeX (pronounced "tech") is a powerful typesetting package developed by Donald Knuth of Stanford University. It gives you unprecedented control over the appearance of typeset output and is especially valuable for setting "penalty" text such as mathematics, tables, foreign languages, technical material, and so on. You can get the complex output in figure 1 by typing:

$$F(b) - F(a) = \int _a~b f(x) dx $$ $$f(x) = \lim _{\delta \rightarrow 0} {f(x + \delta) - f(x) \over \delta }$$

The TeX system was written in Pascal to be portable, and it has been installed on a variety of mainframes, primarily at universities and research institutes. (The source code is available from Knuth at a nominal cost.) Despite its portability, however, TeX typically takes some time and effort to install on a new machine due to its size and complexity. Only recently has it become available on a low-cost microcomputer system, and two very nice TeX systems are now available for IBM Personal Computers MS-DOS machines.

How TeX Works

TeX is a formatter, not a word processor. You can compose your text using any editor that produces a straight ASCII file and insert commands in the text file to control the appearance of the final document. Then you send the ASCII file to the TeX program, which reads and processes it. TeX writes a DVI (device-independent) output file that consists of tightly coded commands to accomplish, for example, the following: move to such-and-such location, set character n from font m.

You run the DVI file through a DVI driver to actually print the typeset file on an output device. These DVI drivers are not part of the TeX package itself but are developed independently for each different output device. The final output looks the same— except for resolution— no matter what device you use. You can print draft output at 1 20 dots per inch on a dot-matrix printer, then run a^preliminary distribution copy on a 300-dpi laser printer, and then typeset the final version on a 1200-dpi phototypesetter.

The TeX system has a powerful macroprocessing facility and is virtually a language unto itself. Large libraries of macros have been created to handle a variety of typesetting chores. Such macro packages can hide the technical details of the particular design from the user while giving the designer great flexibility in creating a unified document style.

For example, you could create a macro called \title that skips 20 points, centers the text that follows it, prints the text in 14-point boldface roman, and skips another 20 points. If you change your mind about the style you want in the document, you can simply change the definition of \title so that, for instance, it moves to the top of a new page, prints 16-point small-caps text, and skips 30 points. You don't need to change anything else in the document.

TeX can accept such macro packages as input in two forms: as straight ASCII text files or in a highly compressed form called an FMT (formatted) file. The second form is desirable for packages that you use often because it is much faster. There are many standard packages of TeX macros, such as AMSTeX, LaTeX, and so on, that aid in document design. These are usually provided in ASCII form and then converted to FMT form at each installation, since the FMT form has some machine-dependent features.

PCTeX AND MicroTeX ON THE IBM PC

Some features are common to both PCTeX and MicroTeX. First, they each require a large system. At a minimum, you need 51 2K bytes of memory and a hard disk. If you want to load all the fonts provided, the systems can each use up to 6 megabytes...

No hablaremos del tema de portada, porque podría provocar mareos y vómitos entre el público, pero sí mencionaremos que habla de aproximar funciones, de invertir matrices o de resolver ecuaciones diferenciales con el método de Runge-Kutta 🤯 (a mí su variante RKF-4, citada en el artículo, me la explicaron en Cálculo Numérico de, creo recordar, segundo de mates) o con series de Taylor.

Sí hablaremos, eso sí, de cuando Pournelle (estoy por comenzar a llamarle Jerry, que ya es casi de la familia) se para de nuevo en el Amiga (y el ST) y sigue viendo que cualquiera de los dos sistemas podría haberse comido el pastel del Mac (esnif).

Amiga

The Commodore folks were not at COMDEX. They'd reserved space but didn't use it; instead, they held a press conference. The official line was that Commodore is selling all the Amiga computers it can make and thus has all the dealers it needs; it would be silly to spend all that money just to tell potential dealers they can't come aboard.

Atari's comment on that was, "We sell more Atari 520S'1S than Commodore sells Amigas, and we sure want to sign up more dealers." The rumor in the pressroom was that Commodore's bankers were signing its checks and wouldn't advance the money to pay for COMDEX.

I wouldn't know. What I do know is that the Commodore Amiga is one hell of an exciting machine.

Amiga versus Atari 520ST

I've had an Atari 520ST and an Amiga set up side by side for about a week. One thing is clear: either one of these machines could eat Apple's lunch. Both machines have sharp, crisp color graphics. Neither one has a text editor good enough that I'd use it to write books, but that's a software problem: both the Amiga and the 520ST can display professional-quality text in color. It shouldn't be long before someone writes editors transparent enough for creative writers. Indeed, we already have TDI Modula-2/ST up on the Atari, and it wouldn't take a heck of a long time to write a good text editor.

In addition, both the Atari-and the Amiga have versions of EMACS, the popular programming editor written by Richard M. Stallman. I haven't worked with the current versions, but real EMACS can be customized to know what language you're programming in, making the programmer's life much easier.

By the time you read this, both machines will have Lattice C. Lattice also has a bunch of software tools, like r Ifext Utilities and MacLibrary, a collection of C functions compatible with Macintosh QuickDraw. Software developers are enthusiastic about these: they make it easy to convert Macintosh software to the Amiga. Meanwhile, Borland is porting Turbo Pascal to the Amiga, and, as I've already mentioned, we have TDI's Modula-2 for the Atari. The Amiga's Microsoft BASIC is, as I write this, greatly superior to the Atari's present BASIC, but once again things are changing rapidly. Metacomco, a reliable outfit, is working with Atari, and its Personal BASIC ought to be up on the Atari well before you read this. Moreover, Metacomco is also working with Lattice to bring Lattice C and Ibolkit to the Atari. There won't be any shortage of programming languages for either machine.

Amiga has one major advantage. Microsoft is emphatic about having no plans whatever to port anything to the Atari; but Microsoft's Excel is still the best spreadsheet on the market, and by a lot. The 520ST with Excel would be a dynamite combination and would practically guarantee Atari's penetration into the business world. Excel is written in C for the 68000-based Macintosh, and both the Atari and the Amiga are 68000 machines; it wouldn't be that hard to get Excel onto either one.

The story I get is that Atari was originally going to run with Microsoft Windows, but when Microsoft didn't have Windows running in time for the 520ST's release, Atari went with Digital Research's GEM, which irritated Microsoft no end. Whatever the story you're likely to see Excel on the Amiga long before it gets to the Atari 520ST. It'll be a good combination, too. Meanwhile, there's already powerful business software for the Atari, including DB Master and Quickview's Zoomracks.

In my judgment, the Atari and the Amiga between them spell big trouble for Apple. I haven't seen anything you can do with a Macintosh that you...

Lo de que el ST iba a ser Windows sobre Motorola 68000 es el WTF más importante que haya leído yo en lo que llevamos de repaso de la revista. ¿Os imagináis?

Y sigo con «Jerry» viéndose venir la revolución que iba a suponer el CD-ROM. Desde 1986. Puntos para él, que la cosa no era tan obvia.

The Information Revolution

We've seen it coming for a long time, but now the CD-ROM is here. CDROM is the name agreed on for using compact disks as read-only storage for computer information. The CDROM disk drive is about the size and price of a good floppy-disk drive. Each CD-ROM disk can hold hundreds of megabytes of information: programs, data, text files, music and speech, animation and motion pictures— all can be put onto the disk and accessed.

Phillips has CD-ROM drives for sale, and there are already a number of commercially available CD-ROM disks, along with software to access the data. Activenture, Gary Kildall's new company has Grolier's Academic American Encyclopedia with a really neat indexing system; in a few seconds to tens of seconds, you can search through the whole encyclopedia. It took less than a minute to find all the references to science fiction (about a dozen) and all references to science fiction with the name Pournelle in the same article (alas, none).

The Phillips people tell me there are about 40 databases on CD-ROMs. These include back issues of newspapers, stock-market histories, all kinds of financial data, technical manuals, math handbooks, you name it. Many haven't been announced yet, but Phillips is aware of them. Meanwhile, software to access these databases is either in preparation or, like Kildall's, already available.

CD-ROM disks can be manufactured for about $5 each in quantity and contain all the text information in the Encyclopaedia Britannica. A single CD-ROM disk can contain more text than the best industrial-quality line printer will print over its useful lifetime. A set of 20 of those disks would make an encyclopedia like nothing that ever existed: illustrations could include motion pictures and stereo. The article on space could include shots of Apollo 1 1 taking off, and so forth.

It can't be long before this technology changes the way we look at and use information. Couple a CDROM disk drive to an Atari, and you have the potential for a powerful educational system: the greatest teachers and lecturers in the world complete with every demonstration tool they ever wanted. Want to explain the solar system? You can be a talking head for a while, then switch to color animated models, first of the planets in their orbits, with speedup at perigee and slowdown at apogee; color bars to show that the planets sweep out equal areas in equal times; and actual Voyager photographs of the planets themselves. Moreover, a section on integral calculus could use the planetary orbital animation to illustrate just what an integral is.

Now, true, the educational lobby will try its best to hang on to "credentialism" and will continue to insist that no fundamental changes be made in our present educational system. But no matter how hard educators drag their feet, this new technology can't be stopped. Not only the Library of the Month Club but the College Course of the Month Club have just become realities.

CD-ROMs will change the whole nature of scholarship. Even after all these years, only a handful of scholars have had access to the original text of the Dead Sea Scrolls; now, everything known about them, including...

Ante un pequeño alud de software para el ST y el Amiga, Bruce Webster dejaba la segunda parte de su comparativa de ordenadores basados en el 68000 de Motorola para el mes siguiente…

Amiga Software

As mentioned last month, Amiga software has just started to hit the shelves. In the past week, I've received about a dozen programs, all coming from just two publishers: Electronic Arts and Lattice.

As with the ST, the best Amiga program so far is a painting program: Deluxe Paint, written by Daniel Silva and published by Electronic Arts. Deluxe Paint is reminiscent of MacPaint— a menu bar across the top, icons along one side— but there's a big difference: color. And lots of it.

What really makes Deluxe Paint stand out are its features. Let's start with the color palette. In low-resolution mode (320 by 200 pixels), you can have 32 different colors (out of a possible 4096). Like DEGAS, you can individually adjust each color. But the palette's functions don't stop there. You can select any two colors on the palette and have it automatically generate a set of intervening colors. For example, if color #5 is pure red and color #15 is pure green, the spread function will turn colors 6-14 to shades that go from red to green— in this case, passing through orange and yellow along the way. I was able to easily generate a "rainbow" palette by creating the classic rainbow colors (red, orange, yellow, green, blue, indigo, violet) at regular intervals, then using the spread function to create intervening shades. Like DEGAS, you can set up a range of colors to cycle through; unlike DEGAS, you can define up to three different cycle ranges, each with its own speed.

As for painting, you have most of the tools found in MacPaint and DEGAS— like lines, filled and framed shapes, etc —and quite a few found in neither, like the ability to do smearing, shading, or blending of the colors. You can grab any rectangular portion of the screen and use it as a brush. You can save and load brushes, which gives you an effective "clipboard" for saving chunks of pictures.

Comparing DEGAS (on the ST) and Deluxe Paint (on the Amiga) isn't easy, if simply because they are on two different computers. I prefer the two-screen user interface of DEGAS; it's easier to learn and a bit less cryptic. Deluxe Paint, on the other hand, has significantly more capabilities and options. Just about everything that DEGAS lets you do, Deluxe Paint lets you do in more ways and with more options, though there are a few things that DEGAS does better (or that Deluxe Paint just doesn't do). And like DEGAS and the ST, Deluxe Paint is a program you should buy if you own an Amiga.

Three of the remaining EA programs are games: Seven Cities of Gold, One on One, and Archon. Unfortunately...

Nótese la admiración por Deluxe Paint, absolutamente merecida.

Y nos vamos (este mes os lo he hecho breve) con un anuncio para no dejar desierta la categoría de «cosas que creemos que se han inventado ahora, pero no»:

Ilustración minimalista, con una enorme área negra en los dos tercios de la derecha en negro y el tercio de la izquierda en azul. En la frontera entre el blanco y el azul parece una bola de luz de la que salen algunos filamentos brillantes. Hay un nombre en grande, Guru, y un texto que dice Introducing software with a mind of its own.

Sí: hace 40 años la IA ya se iba a comer el mundo de los negocios. (Micro Data Base Systems, la empresa del anuncio, había lanzado un gestor de bases de datos un par de años antes, que vendían como un dbASE más potente y ¡con SQL! (SQL es del 73, pero no se estandarizaría hasta el 86) y lo complementaban ahora con un «entorno de soporte a decisiones», KnowledgeMan, y Guru, un «sistema experto»revolucionario sistema de IA».)

Pues eso: hasta aquí la Byte del mes. Si queréis hacer los deberes para el mes que viene, como siempre, aquí tenéis los archivos de la revista Byte en archive.org.

Lecturas (2026.II)

Comenzamos con una lectura ligera… pero no tanto, porque el surrealismo es considerable en esta historia de Raquel Gu y Javier Pérez Andújar, que en ocasiones se preocupa más de su humor absurdo que de tener muy claro dónde tiene los pies y dónde la cabeza. Aun así, divertido, fácil y recomendable para desconectarse un rato del mundo.

Uno se ha leído en su vida unos cuantos libros de Bill Bryson. No todo lo que ha escrito, porque eso es casi un trabajo a tiempo completo, pero en cualquier caso, unos cuantos de los libros. El tipo tiene una cultura inconmensurable y un estilo en general divertidísimo de contar las cosas. No sé por qué, en esta ocasión el libro no me ha divertido tanto como otros que me había leído con anterioridad. Por algún motivo, el tono de viejo gruñón que se ríe de sí mismo más que de lo que se queja no me ha funcionado demasiado, y con una cierta frecuencia se me ha quedado en viejo gruñón a secas. (¿Podría ser que el viejo gruñón fuese yo y no Bryson? No podemos descartarlo.)

Mención aparte para las notas al pie de la edición Kindle: la traductora (Mireia Rué) se lo curra hasta el infinito para trufar el libro de notas para hacer comprensibles todas las referencias extremadamente british a los que no lo somos… (¡gracias!) pero, al menos en la app de Kindle para Android en mi Boox Nova Air, las notas son básicamente ilegibles :-S.

Ya nos hemos declarado fans en alguna otra ocasión de Octavia Butler. En esta ocasión tocaba una novela corta (cortísima: 35 páginas) que se hizo con el Hugo, el Locus y el Nebula. Se hace, efectivamente, corta, pero es sobrecogedora en grado extremo. Puede echar un poco para atrás por lo escabroso, pero me ha parecido genial.

Otro autor que nos entusiasma, y otra historia breve, en esta ocasión un pelo más de 150 páginas. Si Millás escribiese la previsión del tiempo, lo más probable es que por aquí la leyéramos con devoción. Deja, eso sí, la duda que debe generar un señor escribiendo un personaje femenino, especialmente si es como el de la novela: ¿perspectiva de género razonable, o exceso de mirada masculina?

Y cerramos con otra autora que ya habíamos visitado. Esta vez Mary Beard, en un ejercicio bastante meta, se fija en los clásicos doce césares, pero con el objetivo de ver cómo sus representaciones a lo largo del tiempo (llegando prácticamente hasta el presente) retratan cómo hemos visto y vemos el poder. Imagino que habrá otros libros mejores para repasar las historias de esos doce césares, pero si te interesa más lo que dice la historia como disciplina que la historia que cuenta (es mi caso), te lo vas a pasar pipa.

(Por cierto: millones de notas al pie que, a diferencia del libro de Bill Bryson, se pueden leer perfectamente.)

A ver cuándo (o si) llega la tercera edición de 2026 del lecturas…

Dispositivos para interactuar con el ordenador: Tourbox Lite y el touchpad de Amazon

Diría que hacía un buen tiempo que no hablábamos de cacharritos por aquí fuera de los repasos a la revista Byte [consulta sus notas: no tanto, pero no somos lo que fuimos… la anterior entrada en enero, y antes de eso, en agosto del año pasado].

Uno es, mal que le pese [nota del editor: no le pesa], un adicto a los cacharritos que suponen maneras diferentes de interactuar con la tecnología. Y últimamente han caído en el escritorio de obm un par de ellos…

Foto de primer plano de una mesa, con un teclado de ordenador a la derecha (como referencia de tamaño). A la izquierda podemos ver una cajita con botones de formas diversas (dos son redondos, hay cuatro más de formas redondas, y un par de ruedas: una de ellas como la ruedita de un ratón de ordenador, la otra más parecida al control de volumen de una radio. Al lado de esa caja, hay un touchpad, de unos quince centímetros de diagonal. Ambos dispositivos son negros.

Comencemos por la Tourbox Lite, que llegó antes (y no fui yo, señoría: ¡soy inocente!). La excusa (como si nos hiciese falta) es que muchos programitas de edición audiovisual ganan si les aparecen rueditas y otros botones para que podamos usar la «memoria muscular» y trabajar algo más deprisa. (En mi caso, el software es Adobe Audition, que para algo tengo un podcast.)

Y, sin alargarnos mucho, la cosa funciona. Tener unos pocos botones a los que les puedes asignar las funcionalidades más habituales, y poder usar las rueditas para cosas como zooms o los «sliders» del programa de turno, hace las cosas un poco más eficientes. Supongo que solo se justifica el gasto si haces un uso intenso de ese tipo de software, pero como a mí me salió gratis… 😅

En la foto podéis ver que el cacharro está conectado por cable, pero hay versión Bluetooth para los alérgicos a los cables. Y si echáis en falta más botones, tenéis la Turbox Elite, e incluso la Elite Plus (a mí me vienen grandes, claramente).

Y por el otro lado, el touchpad. Uno ha sido siempre de ratón, pero tenía una cierta envidia del touchpad que vende Apple para sus ordenadores… pero no la suficiente como para dejarse los 139 eurazos que cuesta. En algún momento busqué alternativas, pero lo que había en el mercado era bastante cutre (o me lo parecía a mí, como mínimo). Para mi sorpresa, hace unas semanas vi que Amazon tenía uno en su línea Basics y los menos de treinta euros del precio acabaron con mi ya de por sí no muy rígida resistencia. Y, oiga, pues será de la línea Basics, pero a mí me parece que el producto es más que decente. Como podéis ver en la foto, es enorme (6,4″ de diagonal). No podéis ver que el clic es físico, y no háptico, que es lo que se lleva ahora, pero a mí me sirve perfectamente. El soporte para los gestos «multidedo» es bueno y, a ese precio, no sé encontrarle problemas, la verdad. Podría usarlo más, ciertamente, pero, insisto, por apenas 30 euros…

Apa, eso es todo.

Bueno, no, falta una cosa: si seguís los enlaces a Amazon, sabed que son de su programa de «referrals»y que, en caso de compra, me llevaría una pequeña comisión.

Byte, marzo del 86

Proseguimos con nuestro proyecto de leer la revista Byte, cuarenta años más tarde. El resto de entradas de la serie, como siempre, las encontrarás en la etiqueta Byte de obm. En enero habíamos hablado del Atari 520ST y este mes toca el hermano mayor, el 1040ST.

Portada de la revista Byte. La ilustra una foto cenital de un ordenador, con su monitor (de tubo, claro) y su ratón de dos botones. Hay un segundo tema de portada, Homebound Computing

Destaco, en primer lugar, un megaanuncio de Microsoft publicitando sus lenguajes de programación.

Solo pongo la portada, porque se alarga hasta siete páginas más, que el catálogo de Redmond era extenso y su presupuesto para publicidad profundo. Sirve el anuncio, además, para ver cuáles eran los lenguajes que Microsoft consideraba importantes en la época. Arrancan con C («First with the pros«), Macro Assembler («The Quickest. Bar none«), FORTRAN («The overwhelming favorite«), COBOL («The interactive edge«), Pascal («When you’ve outgrown the others«) compartiendo página con QuickBASIC («BASIC just got faster«), que ilustraban, si no me equivoco, con una HP12, y cerraban con LISP («The language of artificial intelligence«), muMATH («Mainframe math on your PC«) y Sort («Versatility without compromise«), compartiendo página también.

¿Quién esperaba ver a FORTRAN y COBOL ahí arriba en 1986? Yo, no. Ni siquiera recordaba que Microsoft hubiese tenido un sistema de álgebra simbólica…

Y de la publicidad de lenguajes saltamos al programa que, en una realidad paralela a la nuestra, ocupa el lugar de Photoshop: el mítico Deluxe Paint (aquí, una carta de amor al Deluxe Paint III), que en aquella época no le sacaba los colores (see what I did there?) a los de Adobe… porque Photoshop 1.0 no llegaría al mercado hasta el muy lejano año de 1990.

Drawing and Painting Program for Amiga

Electronic Arts has released a graphics package for drawing and painting with the Amiga. Deluxe Paint, first in a series of arts software for the Commodore machine, has 20 drawing tools, 7 painting modes, 14 special-effects tools for brushes, 10 built-in brush shapes, and a palette of 32 colors (out of a possible 4096).

Deluxe Paint's drawing tools include magnify and zoom functions that let you split the screen into a normal image and a magnified portion of the image. As you zero in on and alter details in the magnified window, changes are reflected in the normal window. Another tool lets you customize paintbrushes. Anything you can draw can be framed, picked up, and used as a new paintbrush.

The package offers four types of brushes: circles, squares, dots, and airbrush. You can rotate any brush 360 degrees, flip it vertically or horizontally, stretch it into new shapes, or shear its angles. Shading and smearing capabilities help with texture and nuance.

You can create animation effects with what Electronic Arts calls "color cycling—cycling a variety of colors through a static picture to concoct the illusion of motion. You can use three different color cycles and speeds per picture.

Five color controls let you handle the mix of red, green, and blue and adjust the hue and brightness of each color. The software enables the Amiga to automatically generate the shades of color between any two pigments you pick.

Deluxe Paint, priced at $79.95, is designed to work with two other programs still in the Electronic Arts workshop, Deluxe Print and Deluxe Video Construction Kit (reportedly slated for April release). It requires 2 56K bytes of RAM and Kickstart 1.1.

Me paro un momento en la sección de libros para recordar al muy mítico (en aquella época) Peter Norton. Si tuviste un PC con MS-DOS, muy probablemente recuerdes sus míticas Norton Utilities (que ¡siguen existiendo!), pero a lo mejor no sabías que era un autor de «best sellers» sobre la programación del PC.

BOOK REVIEWS

THE PETER NORTON PROGRAMMER'S GUIDE TO THE IBM PC Peter Norton Microsoft Press Bellevue, WA: 1985 426 pages. $19.95

THE COMPUTER CULTURE Denis P. Donnelly, editor Fairleigh Dickinson University Press Cranbury, NJ: 1985 176 pages. $24.50

MICROSOFT MACINATIONS Mitchell Waite, Robert Lafore, Ira Lansing Microsoft Press Bellevue, WA: 1985 497 pages, $19.95

THE COMPUTER LAW ANNUAL 1985 Miles R. Gilburne, Ronald L. Johnston, Allen R. Grogan, editors Harcourt Brace Jovanovich New York: 1985 405 pages, $60

THE PETER NORTON PROGRAMMER'S GUIDE TO THE IBM PC

Reviewed by Donald Evan Crabb

Although the information Peter Norton provides in The Peter Norton Programmer's Guide to the IBM PC is not new or unique, reading it is an education. The book picks up where Norton's Inside the IBM PC (Robert J. Brady Co., 1983) left off. Whereas the earlier book concentrates on the hardware components of the IBM Personal Computer and how they work together, the new book is written strictly with the PC programmer in mind. Both works combined provide a comprehensive technical reference to the PC. As you might expect, these books cover some material in common. For example, both explore the ROM BIOS of the PC. But the discussion in The Programmer's Guide is designed for the programmer. In fact, this book should be useful to anyone who needs to understand the technical details involved in creating PC programs. Norton makes the distinction right from the start that he is providing more than just PC programming knowledge. He is trying to impart concepts about PC programming.

Norton also concerns himself with the philosophy of programming the PC. He laces the book with explanations about the design concepts that permeate the entire IBM PC line. Due to Norton's wealth of experience working with PCs, this information is synthesized so that it is more useful than the usual dry engineering discussion that you often get in books of this kind. He carefully divides the ROM information into four chapters: ROM BIOS basics, ROM BIOS video services, ROM BIOS disk services, and ROM BIOS keyboard services.

The Programmer's Guide details the original PC. But keep in mind the subtitle of this book: "The ultimate reference guide to the entire family of IBM personal computers." Norton explains differences between the design, construction, and systems software of the other members of the PC family and the PC. Most of the examples and information describe the Intel 8088 microprocessor and how it's programmed through the services provided by the ROM BIOS and by DOS. Many of the programming examples use BASIC as the representative high-level language. Pascal and C-language examples also appear. Norton shows how to write 8088 assembly-language interface programs for each of these languages.

The scope of the book extends to a number of programming areas. From video and disk basics, Norton moves from how the keyboard operates in programs to all the programming aspects of DOS. The final two chapters, "Program Building" and "Programming Languages," are worth the price of admission alone. Norton covers the conceptual basics of writing, compiling and interpreting, linking, and executing programs. Especially informative are the discussions of the DOS LINK program and the logical organization of assembly-language programs.

Norton discusses both the IBM Pascal compiler and the generic Microsoft Pascal compiler. He discusses Pascal data formats on the PC and how to work with them, as...

(Si tuviese más tiempo y dinero de los que tengo, seguramente haría por obtener una copia del Computer Law Annual 1985, porque por la crítica parece digno de leer con curiosidad histórica, con artículos sobre los problemas de propiedad intelectual de la ingeniería inversa, o la normativa antitrust, aunque también dicen que está escrito para juristas.)

No me alargaré mucho con el ordenador protagonista del número: a estas horas ya deberíais tener claro que el ST era mejor que el Mac (y del Windows de la época ya ni hablemos)… pero que estaba por debajo del Amiga (con la excepción de las aplicaciones musicales: ¿sabíais que Fatboy Slim sigue usando un ST?).

The Atari 1040ST

A megabyte of memory for $999

Editor's note: The following is a BYTE product preview. \t is not a review. We provide an advance look at this product because we feel that it is significant. A complete review will follow in a subsequent issue.

Atari's new $999 1-megabyte 1040ST (see photo 1) establishes a price break reminiscent of the Commodore 64's. And, as table 1 shows, the 1040ST will be the first computer to begin its retail life at a price that represents less than one dollar per kilobyte. The 1040ST is clearly a bargain, with over 1 megabyte of RAM (random-access read/write memory), its operating system in ROM (read-only memory), an internal 720Kbyte double-sided drive, an internal power supply, and the same features and functionality that already make the Atari 520ST an attractive purchase. (Editor's note: See "The Atari 520ST" by }on R. Edwards, Phillip Robinson, and Brenda McLaughlin. January BYTE, page 84. |

System Description

Our coverage of the 520ST adequately describes most of the features of the 1040ST (see also the "In Brief" box on page 86). The new computer has the same keyboard, the same ports (although these are now in new locations, see photo 2), and the same architecture. We remain uncomfortable with the keyboard, but the keytops are removable. We suspect that some speedy entrepreneur will provide alternative tapered keys for the ST machines.

The most obvious changes are cosmetic: The keyboard/computer unit is 2 inches deeper and 4'/2 pounds heavier than the 520ST and the keyboard provides a much more substantial feel. The mouse/joystick ports are now located under the bottom right front of the unit, a significant improvement for left-handed users.

A number of changes are more than cosmetic. The internal power supply eliminates two of the external power supplies needed by the 520ST (wire haters rejoice). We left the unit on for five days and experienced no difficulties with overheating. There is no internal fan, but the unit appears to adequately dissipate heat. The internal disk drive supports both single and double-sided disks. An RF (radio frequency) modulator will allow you to hook up the 1040ST to a television set; you might, therefore, obtain the high-resolution monochrome system for word processing and programming without sacrificing the use of low- and medium-resolution color. However, we received a preproduction unit lacking the RF modulator that will accompany the final product; therefore, we were unable to test the television quality of the computer's output.

The megabyte of RAM in the 1040ST isn't crammed into the case. The 520ST uses a custom Memory Controller chip to handle its sixteen 2 56K-byte dynamic RAM chips. The 1040ST uses the same Memory Controller. Because the controller can handle 32 RAM chips at a time, the Atari engineers simply had to find room for 16 more 2 56K-byte dynamic RAMs on the 1040ST circuit board to pump RAM capacity to a full megabyte (see photo 3). In fact, the Memory Controller can also govern 1 -megabit dynamic RAM chips. Atari should have little difficulty designing an ST with 4 megabytes of memory. Undoubtedly, the most interesting addition to this computer, apart from the extra memory, will be an empty socket for a graphics coprocessor. Our preproduction unit also did not include the socket, and it may not be offered with the first releases of the 1040ST Phil Robinson discussed this and Atari's future plans with Shiraz Shivji, vice president of research and development for the company (see the text box "An Interview with Shiraz Shivji" on page 90).

TOS IN ROM

With TOS (the operating system for both the 520ST and the 1040ST) in ROM, the 1040ST boots more quickly than the 520ST. [Editors note: Atari is currently supplying the ROM chips to 520ST developers and will be making the chips available through users groups.] Booting with a nonsystem disk takes less than 6 seconds, down from 37...

Los de mirada afilada habréis notado que en la portada, además del ST, había un segundo tema, el «homebound computing». ¿Que qué es eso? Nos lo cuenta el primer artículo del tema, que comienza recordándonos que el teletrabajo no lo inventó el COVID, y que ya se hablaba de ello hace cuarenta años, pero que anuncia que el tema se va a centrar en la informática como ayuda para las personas que, por el motivo que sea (una discapacidad, por ejemplo), no pueden desplazarse.

WORKING AT HOME WITH COMPUTERS

by Jane Morrill Tazelaar

For some, telecommuting is a choice: for others, it is the only option

THERE ARE MANY REASONS for wanting to work at home. Some of them involve disabilities that make it impossible or impractical to work in an office. For many disabled persons, the alternative to working at home is no alternative at all; it is the only work they can do, the only way they can become productive members of the work force. Some people work at home because of priorities such as being available to young children, especially during the preschool years. Many parents of small children must choose between sending them to daycare centers or babysitters and earning a reasonable living. Other reasons involve the lack of local work opportunities in economically depressed or geographically remote areas. And for some people, working at home is a simple matter of choice. The electronic cottage, the flexiplace, telecommuting, worksteading, or whatever you wish to call it could be the answer to all these problems.

Starting Your Own Business

Starting your own business seems to be the answer for many people. There is a certain romance in the very word entrepreneur, and there is a great deal of information available to help you get started if the idea of being one appeals to you. The various organizations associated with the cottage industry movement— the Association of Electronic Cottagers, the National Association for the Cottage Industry, and the National Alliance of Homebased Businesswomen— offer good and helpful information for the aspiring entrepreneur. (See the text box "Sources Mentioned" on page 1 56 for addresses and phone numbers.) They also offer countless references, contacts, and, possibly most important, support groups.

Two subjects seemed to jump out at me from all the literature I have seen on starting your own business: selling and networking. First, if you don't want to sell, you probably don't want your own business. Most business ventures involve direct selling. Whether you provide a product or a service, you need to sell it. Even if you have salespeople working for you, you have to sell the idea to some financial institution to get funds to get started and to the people you hire to get them to work for you. Then, long after the basics are in place and you are operational, you'd better be prepared to talk about your product or service, explain its value, and convince a prospective buyer that he or she ought to do business with your company instead of someone else's— in other words, sell.

Networking is a way to increase your contacts. Whether people are business contacts or social contacts or both, they can add significantly to the success of your business. The people you know either personally or electronically are sources that can provide you with future customers, business partners, financiers, good tax accountants, awareness of your competition, discounts on computing equipment, the inside story on future technology, and so on.

Starting your own business is a very rewarding venture for some and a complete disaster for others. At the...

Me salto el artículo sobre síntesis de habla a partir de imágenes para pasar directamente al e-learning, que me toca la fibra especialmente.

THE ELECTRONIC UNIVERSITY NETWORK

by Donna Osgood

Get a degree without ever leaving your computer

UNTIL RECENTLY, education at home meant correspondence courses. Taking courses through the mail is a slow, cumbersome way to learn, and for many people it means missing out on a vital part of the education experience: contact with a human instructor. Without that, you can easily lose interest in the course and drop out.

Meanwhile, as the baby boom generation passes, colleges faced with declining enrollments are looking for ways to reach a wider range of potential students. They need to reach people who would not ordinarily be willing or able to matriculate in the traditional way.

TeleLearning's Electronic University Network addresses both problems. Through the Network, universities offer accredited courses to students who enroll, participate in "class," interact with instructors and other students, and take tests on the material they have studied, all without leaving their microcomputers. Since classes are small (usually 10 students per instructor) and feedback on each assignment comes within a day or so, students taking courses from colleges through the Electronic University Network get much more individual attention than they would in a large class on campus. Some of the other benefits of telecommunication apply here as well: An instructor can judge a student only on the basis of his or her work, without interference from preconceived notions and biases based on how the student looks, speaks, or acts.

Founded in 1983, TeleLeaming began offering accredited courses in March of 1984. In January 1985 it established full-fledged degree programs, and it now offers two associate degrees, two bachelor's degrees, three MBAs, and specialized professional certificates. The degrees are awarded by fully accredited colleges (Thomas A. Edison State College in Trenton, New lersey, City University in Bellevue, Washington, and lohn F. Kennedy University in Orinda, California). The Electronic University itself offers no credit, acting solely as a coordinating medium and resource center for students. About 17,000 students have enrolled.

Courses available through the Electronic University Network include noncredit courses for personal improvement (writing, computer literacy, drawing, and wine appreciation, for example), business and professional skill classes (time management, accounting, and business math, among others), and tutoring programs for children (reading, math, and computer literacy). Courses for credit span the humanities, natural sciences, mathematics, social sciences, and business at undergraduate and graduate levels.

How It Works

You enter the Electronic University by buying an enrollment package for $150. This one-time fee covers operating software, communications software, and lifetime enrollment in the Electronic University for your entire family. Tuition for individual classes is handled separately. The admissions questionnaire and class registration...

Y es que en 1986, el año en que los módems de 2400 baudios nos parecían lo más, la educación a distancia ya no era necesariamente por correspondencia, gracias a la Electronic University Network de Telelearning. Hay más sobre el tema en Tedium.co y en eLearning Inside, pero el artículo nos explica que la cosa no era ni siquiera «lo último de lo último», porque se había fundado en el lejano 1983 y tenía programas de grado oficiales desde 1985, con 17 000 estudiantes matriculados hasta entonces. Eso sí, los materiales de aprendizaje no eran en línea: te enviaban el libro a casa. Tecnología necesaria: un IBM PC o PCjr, un Apple II o un (cómo no) Commodore 64 (el 35% de los matriculados no tenía ordenador al apuntarse). ¡Y había hasta mensajería instantánea!

Pasar a otro tema del que también, oh sorpresa, seguimos hablando hoy: envejecimiento y tecnología.

INCREASING INDEPENDENCE FOR THE AGING

by K. G. Engelhardt and Roger Edwards

Robotic aids and smart technology can help us age less dependency

FOR THE FIRST time in history, a significant portion of our population is living to be senior citizens, and we have no experience in caring for large numbers of healthy, literate, articulate older persons, many of whom are highly educated. As our society grays, we need more ways to help increase the independence of those with chronic and multiple disabilities. Rapid advances in microprocessor based technologies are providing us with many new possibilities. Their miniaturization, flexibility, modularity, and ever-decreasing costs now make it possible to realistically address human problems that we could not just 10 years ago.

The need to control our environment and our lives in order to reduce dependence is critical to human development. Loss of personal independence is costly, not only in actual dollars spent on institutional and long-term care, but also in emotional and psychological terms. The need to reduce premature and unnecessary institutionalization of our elderly citizens is critical. We need more devices that will increase the independence and the sphere of control of individuals with disabilities and to augment the care givers' tasks with state-of-the-art tools to help them provide better care.

This article discusses potential applications of microprocessor-based technology for increasing independence in those with declining abilities. From panic buttons to smart houses, from stationary telemanipulators to self-navigating robots, from memory-aid devices to expert systems for daily living, microprocessor based technology can assist the functionally dependent older person.

Applications

An applications team was formed during the winter of 1984 to investigate potential uses for robots and robotic related technologies. The team identified 54 subgroups of tasks and divided them into 12 major categories: patient transport-lift-transfer, housekeeping, ambulation (walking patients to help prevent bedsores), physical therapy, depuddler (urine cleaner), surveillance (to help with wandering patients), physician assistant, nurse assistant, patient assistant, vital-signs monitor, mental stimulation, and one miscellaneous group. Let's look at some possible robotic applications in a few of these groups. Lifting and Transferring: The challenge of lifting and transferring individuals with partial or total paralysis, extensive weakness, or increased fragility due to age is significant. One robotic solution could be a track mounted robot arm that glides along the ceiling until it reaches the room to which it has been summoned. The care giver or the older person could then direct the arm to assist in lifting or transferring the individual from bed to chair or wheelchair to bath, for example. This assistance could also help...

Que sí, que hace cuarenta años ya nos interesaba si las tecnologías digitales podrían ser una ayuda para una sociedad que envejecía cada vez más. Y a continuación viene el tema en que nos paramos cada vez en obm: ordenadores y discapacidad visual.

COMPUTING FOR THE BLIND USER

by Aries Arditi and Arthur E. Gillman

Some special human factors must be considered in assembling a workable system

INEXPENSIVE COMPUTERS and nonvisual communications hardware have, in theory, made personal computing as accessible to blind as to sighted persons. But in practice, personal computing has its own special set of problems for the blind user. In this article we'll present some of the human-factors issues specific to nonvisual personal computing. Our concern is to make computers more accessible and efficient for blind and visually impaired persons. We hope our suggestions will be useful to individuals and to designers of hardware and software. Many of the improvements we discuss below can be implemented in several ways, often in more than one component of the system. They are intended to illustrate human-factors issues rather than to critique specific products.

The system we use as a basis for this discussion is a popular one for blind and visually impaired users and is inexpensive enough for home use as well as employment settings. It consists of an Apple IIe microcomputer operating under DOS 3.3, a Votrax Personal Speech System for voice output, and Raised Dot Computing's Braille-Edit program version 2.44a. [Editor's note: There is a more recent version of Braille-Edit with a number of new features and enhancements. See Henry Brugsch's review, "Braille-Edit", on page 251. Also, for an address list for manufacturers of products mentioned in this article, turn to page 208. | Most blind users have a printer for producing sighted (conventional) hard copy. Another useful peripheral is a braille printer, since braille hard copy is easier to proofread than voice output. While we will not specifically discuss braille hard copy, many of the human-factors issues discussed here are relevant to the design of braille printers.

Braille-Edit is an integrated software package designed to satisfy most blind users' needs to process documents. It is intended for use with a low-cost artificial-voice system such as the Votrax Personal Speech System or Street Electronics' Echo series (including the Echo+ speech synthesizer) and various other peripherals. Braille-Edit is not intended to (and does not) make all programs that run on the Apple accessible to the blind user, nor is it particularly useful in programming the computer. But it has a number of desirable utilities for the blind user, such as a translator of text to and from grade II braille (a commonly used coding system similar to Speedwriting shorthand) that makes impressively few errors and a copy facility for copying files to and from a paperless brailler such as the Versabraille from Telesensory Systems Inc. (TSI).

The hardware and software designed to make a system accessible to the blind user can be viewed as an...

El primer párrafo se podría haber escrito hoy… Cuarenta años más tarde, las tecnologías son 10 000 veces mejores, pero los problemas, o son los mismos o hemos introducido barreras nuevas para compensar las que (afortunadamente) hemos tirado abajo.

Y una vez cerrada la sección, nos pasamos a la guerra que se mantenía entre los ordenadores con CPUs Motorola 68000: el Mac, el ST y el Amiga (en orden rigurosamente creciente). Bruce Webster, uno de los autores estrella de la revista, hacía una comparativa que se alargó tanto que en este número solo cabía la primera parte, cuya conclusión es que el Mac está más maduro (llevaba mucho más en el mercado9, el 520ST es una ganga y el Amiga se veía lastrado por los problemas de Commodore, pero era el que apuntaba más maneras…

68000 Wars: Round 1

It is late November— almost Thanksgiving—as I finish writing this, and the editors back in Peterborough are screaming for my column. It's nice to be wanted, eh? However, if 1 don't wrap this up and upload it posthaste, I may be wanted in two or three states. Worse yet, a certain managing editor may end up being wanted for manslaughter, though I doubt if any reasonable jury would convict him. I must type faster...

I now have all three of the prominent 68000 machines: Apple's Macintosh, the Atari 520ST, and Commodore's Amiga 1000. I've had the Mac for nearly two years and the ST and Amiga for less than two months. And the single most common question I get these days is, "What do you think of the |one of the above| as compared to |one or two of the others above|?" Also, a lot of claims and counterclaims have been floating around concerning the relative merits of and problems with the three machines. In this column and the next few, 1 hope to sort out fact from fantasy and present some well-supported— if not completely objective— opinions. (Note: "Objective opinion" is an oxymoron, that is, a self-contradictory phrase, like "intelligent idiot" or "deliverable vaporware.")

Mac versus ST versus Amiga

The format of this column is simple. I'll take a number of different areas, one by one, and give my opinion on how the three machines stack up— who wins, who places, who shows. Where possible, this is based on direct experience. However, since I am not all-seeing or all-knowing, I have asked questions of those with more experience or knowledge, and I've done my best to acknowledge them at the end of the column.

Appearance and Physical Setup

The Macintosh wins this category easily. My 2-megabyte Mac has a 20-megabyte hard disk (MacBottom) and two disk drives (internal and external). The design is clean, attractive, professional, and unique. Better yet, the system takes up less than one square foot (9Vi by 9/2 inches) for the main unit and another 6 by 13 inches for the detachable keyboard, which can be easily moved 3 to 4 feet from the main unit. The Mac itself needs only one power outlet, though the hard disk requires its own as well. It definitely looks good in an executive suite and won't eat up all your desk space.

The Amiga comes in second, resembling the IBM PC (though, in my opinion, it looks nicer). The main unit is 17!/$ by 13 inches, covering more than twice as much desk space as the Mac. The monitor stacks nicely on top of the main unit, but a second (external) disk drive must sit to one side and takes up an 8- by 6-inch area. The detachable keyboard (6 by 16 inches) is larger than the Mac's, but it slides nicely under the main unit when not in use, and it can be moved almost as far as the Mac's. One warning, though: Since the expansion bus is on the right side of the Amiga, adding hardware is going to cause the Amiga to grow wider. The basic system (with two drives and monitor) needs two power outlets.

The ST comes in last, for reasons groused about last month. The main unit is 18!/$ by 9 l /2 inches. It therefore takes up less space than the Amiga, but neither the monitor nor the external disk drives can stack on it, so a complete system takes up much more desk space than either the Mac or the Amiga: A conservative estimate is about 21 by 21 inches. The keyboard is built into the main unit, so you don't have the additional space requirements for that, but you also don't have the flexibility of a detachable keyboard. The ST has a nice design but looks much like a home computer (which it is). Most unfortunate are the thick cables and external power supplies— one for the main unit and one for each disk drive. A basic system with monitor and two disk...

En nuestra sección habitual, temas que ni por casualidad encontraríamos hoy en una revista de informática… ¡las ecuaciones diofánticas!

Diophantine Equations

A man buys some x's at $154 each and some y's at $69 each. If he spends a total of $5000, how many of each did he buy?

Although this problem appears to be from a first-year algebra text, we find that the techniques required are not usually found in a "mainstream" course in mathematics. The equation 1 54x + 69y = 5000 has infinitely many solutions. However, assuming the man bought whole-number quantities, we want integral solutions [x,y] for the equation, and now we need a method for solving such equations.

Diophantine Equations

Equations of the form ax + by = c, for integral a, b. and c and integral solutions (x.y). are called Diophantine equations. No one is certain when or where Diophantus of Alexandria was born. Sources vary from "born about A.D. 50" to "flourished about A.D. 2 50." He is called "the father of algebra," having promoted algebraic notation and algebraic treatment of mathematical problems. Previously, such work was done by "rhetorical algebra" or geometric proofs.

A variety of methods are available for solving Diophantine equations. One of these is modulo arithmetic, a powerful and fascinating concept that 1 may explore more closely in a future column.

A very simple method of solving our original problem comes to mind. Since the equation is equivalent to y = (50001 54x)/69, we can simply try consecutive values of x (from 1 to 32 only) until we get an integral value for y.

Since we are mathematically inclined, such an inelegant approach may not sit well with us. Rather, we may prefer to look for a method of solution based on general principles of mathematics. What can we say in general about integral solutions for an equation of the form ax + by = c?

First, we can readily see under what conditions the equation would have no solution. Consider the greatest common denominator (GCD) of a and b. We will call it d. If d is not a factor of c, the equation will have no integral solutions. Why? Since aid is, by hypothesis, an integer and bid is also one, the value (ald)x + (bld)y will be an integer if x and y are integers. That is, the integers are closed under addition and multiplication. Thus, if eld is not an integer, either x or y must not be an integer.

Diophantus Meets Euclid

This leads us to Euclid's algorithm, which was the subject of my last column in January (page 397). If we employ Euclid's algorithm to determine the GCD of a and b, we can immediately determine whether there are integer solutions to the Diophantine equation by dividing the GCD into c. But we can use Euclid's algorithm for much more than that. To see how, let us reexamine the algorithm with an eye toward solving Diophantine equations. Figure 1 outlines the way the Euclidean algorithm finds the GCD of 1 54 and 69. Their GCD is 1, meaning that the two numbers are relatively prime. Now, to begin our examination of the way to solve Diophantine equations, let's modify our original equation to 154x' + 69y' = 1. That is, we will begin with the case where c is equal to the GCD.

In figure 2, I have rewritten the divisions of figure 1 as equations. In order to find integer values of x' and y' that solve the equation 154x' + 69y' = 1, all 1 need to do is substitute 154-2(69) for 16 in equations 2 and 3 and 69-4(154-2(69)) for 5 in equation 3. After collecting terms, I find that 1 = 13(154)-29(69). Thus, x = 13, y — 29 will satisfy the equation 154x' + 69y' = 1. We will call (13,-29) the basic solution to 154x' + 69y' = 1. Is it the only solution?

Let us write our equation in the general form again: ax + by = c. Now, let n be any integer and d be the GCD of a and b. If we add to the left-hand side of the equation, we haven't changed it...

(Y, para que no digáis que abuso del tema, me he saltado un artículo que comienza con «Windows can be implemented on almost any system with a memory-mapped display»…)

Me paro en la sección de BIX (ya recordaréis: el extracto en papel que hacía Byte de las conversaciones en su servicio en línea) para contemplar el nacimiento de IFF, el metaformato de archivos presentado por Electronic Arts que debería ser la base de cómo trabajamos hoy, y que permitía encapsular múltiples tipos de información (texto, gráficos y audio, para empezar) en un único archivo.

IFF Graphics Protocol

amiga/softw.devlpmt #157, from gregr [Gregg Riker, Electronic Arts]

TITLE: IFF (Information Format Files) Is Available!

I mentioned that I used IFF files with the SlideShow. Allow me to elaborate.

Electronic Arts has a general interest in promoting standards, so we knocked heads with some people at Commodore-Amiga and came up with IFF.

IFF is intended to be used by any and all interested developers. It offers a convenient way of allowing programs to exchange data with one another.

For example, Graphicraft will be able to exchange files with Deluxe Paint and other EA products. The design is extensible, in that you may add your own types to the standard. There are programs available in C (public domain!) that will read and write graphic images in IFF format.

If you're interested in a copy of the spec, please contact Rob Peck at Commodore-Amiga. He can supply you with a copy. If you have any problems or need more information, please contact Jerry Morrison at Electronic Arts, (415) 571-7171.

P.S.: IFF covers graphics, audio, and text and is expandable!

Y cierro con una curiosidad. A estas alturas deberíais estar tan enamorados y enamoradas de las ilustraciones de Byte como yo… y esto es tan claro que ya en aquella época la revista vendía ediciones limitadas de sus portadas:

Anuncio de dos ediciones limitadas de reproducciones de portadas de la revista. Una de ellas es una mano robótica dibujando una mano humana junto a una mano humana dibujando una robótica, y la otra es una ilustración de un disquete de cinco pulgadas y cuarto.

Y hasta aquí la Byte del mes. Si queréis hacer los deberes para el mes que viene, como siempre, aquí tenéis los archivos de la revista Byte en archive.org.

Pero, como venimos haciendo últimamente, no nos iremos sin darle un repaso a los episodios del mes de Computer Chronicles

El primero no es especialmente apasionante, y se dedicaba a las carreras profesionales en informática, incluyendo la emprendeduría… Una cosa a destacar es que no era totalmente necesario tener un grado en informática para encontrar trabajo en el campo: bastaba con unas cuantas asignaturas desde otros grados. Por cierto, que ya hablaban de la importancia de las competencias comunicativas… y ya se comentaba que las mujeres se iban a computer science y no a computer engineering. Tremendo, eso sí, en los breves del final del episodio, cómo AT&T presentaba un sistema de correo electrónico «de bajo coste»: ¡40 céntimos por enviar una página de texto! (Un sello costaba 22). Y con servicio de entrega en mano para personas sin correo electrónico por… ¡siete dólares y medio! ¡De la época! Todo ello mientras IBM presentaba un procesador experimental con 93 000 transistores (el procesador del iPhone 16 tiene… quince mil millones)

En el segundo episodio se hablaba de la computación en paralelo. Solo por ver un superordenador Cray de la época ya vale la pena darle al play. El H. T. Kung al que se entrevista a medio programa, por cierto, está a un grado de separación de Deep Blue, de unos de los primeros «gusanos» de internet, de la fundación de Y Combinator (una de las empresas de capital de riesgo más importantes del Silicon Valley)… y de las TPUs de Google. Se dice pronto. Y el Craig Mundie que sale justo después lideró la investigación y estrategia de Microsoft de 2006 a 2012.

Y para cerrar, dos episodios dedicados a los ordenadores y sus usos militares, otro tema del que seguimos hablando hoy. En esta primera parte se repasa la larga historia de esos usos militares, ya desde el ENIAC, y el enorme papel de DARPA en la investigación en el campo. No os perdáis las demostraciones de simuladores de vuelo de altísima tecnología que palidecen al compararlas con lo que podemos correr hoy en básicamente cualquier PC. Y la investigación en armas autónomas ya había comenzado, con el eventual premio Turing Raj Reddy.

Y en la segunda parte, sistemas informatizados en los barcos de la Armada de los Estados Unidos, capaces de disparar autónomamente (y el rechazo que provocaba la idea entre al menos parte de los militares de la época), o las «star wars» de Reagan… y menciones a coches autónomos.

Os diría que avanzaseis los deberes para anticipar el mes que viene… pero marzo fue el último mes de la temporada 85-86 del programa, y la siguiente temporada no llegaría hasta septiembre.

Y eso es todo por marzo… de 1986. El mes que viene, más.