cacharritos – otro blog más

Byte, junio del 86

Creo que es hora de cerrar etapa. Comenzamos a releer la revista Byte ahora hace casi dos años, en julio del 84, y con esta van 24 entradas dedicadas a 24 números de la revista, y hasta yo comienzo a tener un cierto cansancio del repaso mensual (me puedo desdecir en caso de reclamación por aclamación, pero creo que coincidiremos en que podemos cerrar el ciclo ya, ¿verdad?). Pero no creáis que vamos a abandonar la nostalgia así como así: notaréis que no incluimos la minisección de Computer Chronicles desde el mes de marzo. Pues no es porque se me haya olvidado (por una vez, y sin que sirva de precedente), sino porque, como comentamos en su momento (¡no me estáis atentos!), el programa cerró la temporada a final de marzo de 1986, y no volvió a emitirse hasta el inicio de la siguiente temporada, allá por septiembre del mismo año. Y sí, amiga lectora, amenazamos con repasar mensualmente las Computer Chronicles de la temporada 86/87 a partir de septiembre. (Y me reservo el derecho de seguir leyendo la revista y destacar alguna pieza de vez en cuando O:-).)

Y cerrados los temas organizativos, vamos allá con nuestro último Byte.

Portada de la revista Byte de junio de 1986. El tema de portada es ordenadores y música. La ilustra un teclado de piano de longitud infinita en que las teclas negras son microchips

Cuánto voy a echar de menos estas portadas de Robert Tinney… (Veo, por otro lado, en archive.org, que se van a hacer más infrecuentes, y que apenas durarían hasta mayo de 1988. Otro motivo para ir cerrando etapa.)

Abrimos número con la editorial y el estándar informático en vigor más antiguo que yo recuerde, que lleva en danza desde nada más y nada menos que 1983. Eso no iba a impedir, naturalmente, esa lacra que son los formatos propietarios…

Music and MIDI

Have you noticed the stir going on in the electronic music industry? Take keyboard synthesizers. A significant drop in price has been accompanied by a dramatic rise in capability and sound quality, opening the doors of musical exploration to multitudes of newcomers. We've also seen computer technology claim new territories in music through the advent of MIDI (musical instrument digital interface), a data communications protocol that lets you join synthesizers and computers into small networks for composition or performance. MIDI has stimulated the entire music industry by providing a standard for hardware and software to be used for the production of music. Creativity, efficiency, and productivity are enhanced by the development of computer-based tools aimed at the mystical process of music generation.

The current specification for MIDI has been in existence for four years. It came about through the cooperation of music synthesizer manufacturers around the world, notably those from Japan and the United States. Essentially, a large group of manufacturers got together and decided to add serial data channels to all future electronic music instruments so that events generated on one instrument could be played on remote instruments connected via the MIDI cable. Layers of sound, for example, can be produced from a single keyboard controller by driving multiple sound modules equipped with MIDI inputs. By inserting a personal computer into the middle of all this sound generating equipment, composers can record and manipulate scores much as word processors do text.

The Good News

So we now have a data communications standard for moving music event data between a computer and sound-generating hardware. We can buy instruments from different manufacturers and interconnect them at once. Older versions of music synthesizers, having no compatibility to any other device you might be using, were doomed to eventual obsolescence as newer products were released to replace them. Now it's different— what you get tomorrow can be integrated with what you have today, and it's reasonable to consider building an elaborate system over a period of budget-controlled time. A variety of good MIDI software is now available. We find software that can act as a kind of digital tape recorder for music data; programs that edit, store, and retrieve libraries of synthesizer voice parameters; and software that can display, print, and edit scores rendered in traditional music notation. It's a heyday for musicians of all persuasions. Or is it?

The Bad News

While the MIDI specification goes a long way toward unifying the tasks necessary to the production of music, it does not suggest any format for the storage of MIDI data files. Thus, developers of music software are on their own to adopt a structure for disk files containing MIDI performance data created by the software. And that is precisely what has happened during the development of today's MIDI music software: Each program on each computer produces a data file that cannot be instantly read by any other combination of hardware or software. Furthermore, few, if any, file-converter utilities are available to assist transportation of data between environments. (Of course, there is always the issue of differences among the underlying DOS formats for individual computers.)

A Data File Standard

Utility programs that convert music files from one manufacturer's product to another must be seen as only an interim measure. A better approach would see all the important players get together (in a fashion similar to the one that led to the MIDI 1.0 specification) and hack out a target format for file interchange. If software developers could produce a musical equivalent of the DIF standard used for database files in the business world, users operating in different computer and synthesizer environments would benefit immensely from expanded access to the large body of music data now being stockpiled. This tactic would also let existing products "speak'' to future programs designed to use the target file format.

A number of obstacles present themselves when attempting to derive a convenient, universal method of organizing music data files. That's not to say that no one is trying. Besides continuing development on the academic level at universities like Carnegie-Mellon, Stanford, and MIT, commercial concerns like Roland and Electronic Arts have worked hard in an effort to establish useful guidelines toward the goal of increased music data sharing. In its own way, each organization has faced hurdles, including:

• Some computers have a lot more memory, speed, and display resolution than others. How can a file produced on a more powerful computer be rendered on a less capable machine? What should a minimum configuration consist of?

• Should graphic data for displaying common music notation or some derivative be included with MIDI performance data? Since both types of data might exist independently, and, given that some software does not recognize both, should these two kinds of data be kept in separate, parallel files?

• Should we go further and attempt to design a full-blown operating system for music that could be ported to various computer architectures? This is ambitious but could produce long-term benefits.

Naturally, other important points need to be ironed out. At this time, we invite software and hardware developers to plug in their irons. The success of the MIDI standard offers hope for a standard for file interchange. At the moment, the consumer is getting shortchanged by the inability to move data between music processing programs. The audience for computer music software is growing larger and more sophisticated, and it's up to the leaders in music technology development to provide software standards. We at BYTE want to encourage all concerned to investigate the work already done and then have a series of formal conferences involving a variety of sources. It's not going to be easy, but it has to happen (and soon, too, because I have a lot of music data on IMSAI-8080 cassettes waiting to be uploaded to my Amiga).

—Roger Powell, Contributing Editor

El producto del mes era esta descripción-que-no-review del Macintosh Plus, que introducía la altísima tecnología de ser capaz de acceder a las dos caras del disquete (doblar la capacidad de cada disquete no es poca cosa), pasaba a un mega de RAM y añadía SCSI para conectar discos (hablan de discos capaces de transferir 320 kilobytes –el énfasis es suyo– por segundo). A cambio, Apple es Apple, se caían de la configuración MacPaint y MacWrite, que pasaban a costar 125 dólares de nada. Teniendo en cuenta que el Plus salía a 2600 dólares de la época (unos 8500 actuales, actualizando la inflación), no sé yo si a Apple le venía de aquí.

PRODUCT DESCRIPTION
by Phillip Robinson

The Macintosh Plus

It has more memory, double-sided disks, and an SCSI interface

Editor's note: The following is a BYTE product description. It 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.

The Macintosh introduced personal computer users to technology that has now become commonplace: bitmapped displays, 3 /2-inch floppy disks, and iconic desktop environments. The Macintosh Plus adds welcome double-sided drives, a megabyte of RAM, an industry-standard SCSI interface, a numeric keypad, and a larger, faster ROM of operating system routines. The Mac Plus is also much faster than the 512K Mac, partly because of new software routines and partly because of the additional RAM. One feature that the 512K Macintosh had— free MacWrite and MacPaint software— is missing from the Mac Plus. Both programs are available separately for $125 apiece.

System Description

Most of the technical details in BYTE's February 1984 description of the original, skinny (128K-byte) Macintosh are still apt descriptors for the Mac Plus. It is a desktop, 7.8336-MHz 68000based microcomputer in a small-footprint case containing a built-in 3Viinch floppy disk drive and a 9-inch diagonal, bit-mapped, monochrome display of 512 by 342 pixels. It doesn't have any expansion slots, and it...

Nos paramos unas páginas más adelante para una rara avis, un anuncio de un ordenador MSX en Estados Unidos:

Anuncio a doble página de un ordenador de Yamaha, en elegante color negro. Se trata de un MSX, como reconocerá un lector español, entre otras cosas, porque hay un cartucho conectado al ordenador. El ordenador tiene un lector de disquetes de 3,5 externo, un ratón, y se puede ver que está conectado a una disquetera. También podemos ver una impresora, imprimiendo una partitura musical

Notará la lectora que MSX solo aparece en el texto del cuerpo del artículo, porque la marca, en Estados Unidos, apenas era reconocida. Nótese también el marcado acento musical, destacando la síntesis FM, el software musical y el soporte de MIDI.

En la sección cosas-que-no-aparecerían-hoy-en-una-revista… ¡curvas de Hilbert!

HILBERT CURVES MADE SIMPLE

by Michael Ackerman

This one-subroutine BASIC program uses only global variables

IF YOU ARE INTERESTED in fractal shapes, you are probably familiar with the Hilbert curve. It was among the first of many wild but "self-similar" shapes that astonished mathematicians around the turn of the century.

Hobbyists have discovered the beauty of David Hilbert's creation, and several have written programs to draw it on the high-resolution screens of personal computers. Unfortunately, most of the programs that produce the curve are quite complicated. The demonstration program that comes with the Apple Pascal system contains a procedure that itself contains two more procedures. I had a difficult time following the program's logic.

Niklaus Wirth, author of the Pascal and Modula-2 programming languages, includes a Hilbert curve program in his book Algorithms + Data Structures Programs (Prentice-Hall, 1976). While this program is easy to understand, it contains four procedures that call each other again and again. 1 decided that there had to be a simpler way to...

Atención, por cierto, a la firma del artículo: alguien que se estaba licenciando… en historia, claro.

Y, en el apartado quién-ha-escrito-este-artículo… Robert Moog. Sí, ese Robert Moog. Hablando de síntesis digital, claro:

DIGITAL MUSIC SYNTHESIS

by Robert A. Moog

The many different shapes of the waveform of the present

MUSIC IS ONE of the most information-rich (wide-bandwidth) forms of human communication. A compact disk, for instance, uses nearly 1.5 megabits per second to faithfully transmit a stereo recording, as opposed to the several hundred bits per second needed to transmit a written message as fast as you can read it. Only video, the faithful transmission of which requires over 50 megabits per second, has a significantly higher information density.

Music is also a highly structured form of human communication. The hierarchy of a piece of music may be as deep as that of the federal bureaucracy: Notes, phrases, lines, sections, and movements are carefully arranged to heighten and clarify the intent of the music.

These two general properties of music, wide bandwidth and complex structure, happen to match the information-handling capabilities of today's personal computers. In addition to the personal computer's wide bandwidth (or high speed) and information-organizing and -processing capabilities, you can access a growing list of instruments, accessories, and components designed specifically to produce musical tones in response to high-level digital instructions. These devices owe their existence to rock 'n' roll, the consumerization of digital audio, and dramatic advances in LSI (large-scale integration). They employ a wide variety of sound-producing techniques, each with its own set of features and limitations. This article discusses the general attributes of musical sound and how to produce it, the capabilities of specific sound synthesis techniques, how musicians are using these techniques, and what you can expect the future to bring to digital music.

The Properties of Musical Sound

Music is an arrangement in time (and, to a lesser but still important extent, in space) of a collection of sonic events generally called notes. This is actually a subjective description of music. We hear individual notes only because our ears and mind pick acoustic information apart into events that we perceive to be distinct. What actually exists outside our ears is an ongoing series of vibrations of the air. The graph of air pressure versus time is the waveform, an unbroken pattern, present even in the quietest of soundproof rooms. The ratio between the height of a sound waveform that you can barely hear and one that is so loud that it begins to hurt is about one to a million. That's about 120 decibels. Music, speech, and other normal sounds occur in the upper 60 dB of your hearing range.

You can describe any waveform that tends to repeat as a collection of frequency components, each one of which has a sine waveform. This is the spectrum of a sound.

Thus, any sound has two complementary, equivalent representations: its waveform and its spectrum. The waveform is the sound's time-domain representation; the spectrum is its frequency-domain representation. Together they are capable of fully describing a sound. The relation of the waveform to the spectrum is...

Y siguiendo con el tema musical de la revista, algo que ni me sonaba: fractales musicales. Ilustrados (sonificados, mejor, sí) con código en BASIC para el MSX de Yamaha de hace tres capturas. En 1986 lo de los fractales era una cosa tremendamente nueva: el libro de Mandelbrot, The fractal geometry of nature, se había publicado apenas en 1982.

MUSICAL FRACTALS

by Charles Dodge and Curtis R. Bahn

Mathematical formulas can produce musical as well as graphic fractals

FRACTAL GEOMETRY has exerted a strong influence on a remarkable variety of disciplines in recent years. The sciences are using fractal structures to study a diverse range of phenomena from turbulence to bone structure. In the arts, fractal geometry provides computer graphics with unprecedented possibilities for creating a new universe of visual forms, many of which have an astoundingly realistic, natural look. In music, you can employ the same principles to take advantage of a panoply of new relationships.

In The Fractal Geometry of Nature (see reference 1), Benoit Mandelbrot is careful to point out that the realistic and natural-appearing fractal graphics are not modeled on photographs of nature; rather, they are graphics of mathematical relationships that come surprisingly close to resembling occurrences in nature. So it is with examples of computer-aided composition. They do not sound like rock, or bebop, or symphonies. Rather, they embody abstract relationships that assume the characteristics of certain kinds of music.

There are a number of parallels between computer graphics and computer music. Discussions about fractals and computer graphics usually distinguish between the high-resolution pictures made on powerful institutional computers and those made at home. The same schism exists between highest-quality sound synthesis and home synthesis.

This article discusses some of the basic techniques of computer-aided musical composition and includes some programs for generating musical fractals on home computers. [Editor's note: The programs WHITE. BAS, BROWN. BAS. lOVERF.BAS, VARIATN.BAS, and RANDOM. BAS are written in MSX BASIC using MUSIC MACRO commands for the Yamaha CX5-M music computer. Their source code is available for downloading from BYTEnet Listings at (617) 861-9764. They are also available on disk [see page 445). | The output of the software shown in this article is a list of commands for the computer's internal synthesis hardware rather than actual music. Other details can be found in the text box "About the Programs" on page 196.

A Longstanding Relationship

Since the time of ancient Greece, Western music has embodied propor-

tions and abstract numerical relationships. There are many examples. A famous motet of 1436, Nuper Rosarum Flores by Guillaume Dufay, uses the same relations of tempo between its sections as the ratios in size between parts of the Florentine cathedral for whose dedication it was composed. Numerology played a part in certain choices of elements in some of the religious music of |. S. Bach.

In our own era, Bela Bartok, the great Hungarian composer and folk music expert, used the Fibonacci numerical series to govern pro...

Sin haberle dado al código en BASIC, no sé yo si se tratará de la cosa más armónica del mundo. Buscando algo más sobre el tema, en 1987, la revista Nature publicaba una carta, Is there such a thing as fractal music? Y una búsqueda rápida en Scholar muestra que se sigue escribiendo sobre el tema.

Y un par de cosillas más de hardware para cerrar. Primero, al Atari ST, que seguía avanzando…

The Atari 520ST

by Eric Jensen

A good engine for bit-mapped graphics at an attractive price

The Atari 520ST is a very appealing machine. It is a good engine for bit-mapped graphics, with a good user interface and an attractive price. Still, the review machine had too many rough edges to serve as my primary machine. It is far from portable. A two-drive system put seven boxes on my tabletop and required four wall outlets.

The processor and each disk drive have separate power supplies and the four power switches are inconvenient. I don't like leaving the power supply plugged in while its output is turned off. It draws some power, and I worry that the system will be susceptible to power-line glitches even while turned off. The practical solution seems to be to use a switched outlet box.

Hardware

The hardware appears clean. The 8-MHz clock rate (a bit faster than either Macintosh's or Amiga's) probably translates to about half a million typical instructions per second. There is no other special display support hardware, and none is needed for windowing applications. The display appears to be properly interleaved with the processor so that they do not have to wait for each other. The display generator is an interesting compromise. For the monochrome display, it fetches a word of data and shifts it out a bit at a time to determine the color for 16 successive pixels. For the color displays, it fetches either two or four words in sequence and shifts out a bit of each to develop a color lookup-table index. Again, there are 16 shift cycles before the next words must be fetched. Thus you have neither the situation in which all the bits describing one pixel are in one word, nor that in which the most significant bits for all pixels are contiguous in memory.

As long as this arrangement is hidden under GEM— as it should be for almost all users— this is fine, but there are a couple of cases in which it could be inconvenient. If you were to use multiple planes of memory (with a degenerate color map) to represent multiple overlayed images, then the images would be inconveniently intertwined. If you have to mask out an irregular region in a picture, then you have to know not only the number of words in a scan line but also the spacing between words, which may not be the same in the image and the mask.

The 512K bytes of RAM is enough for most programming, although the operating system for the reviewed machine used more than 200K. | Editor's note: The latest production units for the 520ST and 1040ST have TOS in ROM.| In addition, the screen uses at least 32K more.

The displays are very crisp and clean, with enough resolution to draw pictures of good quality. The 12-inch screens provide almost twice the area of the 9-inch Macintosh screen. The SMI 24 monochrome monitor provides a 640- by 400-pixel display. This allows 22 lines of 110 characters in the directory font, or 20 lines of 77 in the standard font used in BASIC windows (allowing window borders), which is enough to do a fair job of emulating a dumb terminal. There are about 77 dots to the inch horizontally by 65 vertically, which is fine enough resolution to make the jagged edges of diagonal lines fairly unobtrusive.

You can run the SCI 224 color monitor in two modes (640 by 200 pixels with 4 colors or 320 by 200 pixels with 16 colors). The lower resolution mode is the operating system's initial choice. This keeps the aspect ratio of icons the same as on the monochrome monitor and simply doubles their sizes. The jagged edges are noticeable here but not particularly offensive. I was very impressed by the lack of colored "shadow" edges on

…y después, que el viejo hardware se resistía a morir, y como muestra este botón en que se revisan interfaces MIDI… para el Apple II y para el Commodore 64 (🥹).

Four MIDI Interfaces

by Roger Powell and Richard Grehan

MIDI interfaces for the Commodore 64, IBM PC, Macintosh, and Apple II family

Let's assume you have a personal computer and you want to connect it to a MIDIequipped keyboard or other instrument. One of the first things you will need is interface hardware to send your MIDI signals through your computer. The MIDI specification requires a current-loop serial interface operating at 31,2 50 bits per second, so it is going to take something more than just retrofitting an RS-232C port. In this article, we will look at four MIDI interfaces currently available for some of the most popular microcomputers. The TDS-AP for the Apple 11+/ lie and the TDSC-64 for the Commodore 64 are from Syntech Corporation. The MPU-401 for either the IBM PC or the Apple 11 machines is from RolandCorp. The MIDIMAC for the Macintosh or Mac Plus is from Opcode Systems. The interfaces all include at least a high-speed UART with some sort of clock-generation circuitry, a buffered output stage, and an optoisolated input stage. (The MIDIMAC is an exception; it requires no special UART, since the Macintosh's serial ports can operate well above the speed required by MIDI.) However, most of the interfaces we'll look at in this article add extra features such as drum machine trigger signal outputs and tape synchronization inputs and outputs.

Of course, if you are an Atari ST owner, you are probably reading this with a bit of smugness, because the Atari ST has built-in MIDI ports.

TDS-AP

Syntech Corporation's TDS-AP is a MIDI interface on a board that plugs into the Apple II+/IIe. It includes a pair of DIN jacks— one for MIDI in and one for MIDI out— as well as five mini phone jacks: tape in, tape out, foot-switch, clock out and start/stop.

The tape-in and tape-out jacks allow for synchronization with a tape deck. If you have a multitrack tape recorder, you connect the tape-out signal to a line-in signal on a track of your tape machine; this track will become the click track. You then program whatever MIDI software you're running to output a sync tone and record this on the click track. Now connect the line-out signal from the click track to the tapein port on the MIDI interface, and the sync tone that you have just recorded becomes the master clock for the system when you begin to record onto the other tracks of your tape recorder.

You can opt for some hcmds-off event control by attaching a footswitch to the TDS-AP's footswitch jack. For example, we tested the interface with multitrack recording and sequencer software that enabled us to halt the recording process by pressing the space bar or footswitch. If you have both hands busy on a synthesizer's keyboard, it's much easier to operate a footswitch than an Apple II's space bar.

The clock-out and start/stop lines of the interface can be used to drive a drum machine. The clock-out line connects to the clock-in line of the drum machine, and pulses on this line control the machine's tempo. The start/ stop line— just as its name implies— provides trigger signals to begin and halt whatever sequence you have programmed into your drum machine. Of course, you could also use the clock-out and start/stop lines to control a sequencer.

The clock-out and start/ stop lines add features that may not be immediately apparent. Not only do they permit you to control drum machines that are not equipped with a MIDI interface, but they provide a direct control path to a drum machine that might otherwise be at the end of a line of daisychained MIDI devices (and would therefore suffer from signal-transmission delays). They also alleviate the problem that arises if you don't have enough MIDI-thru connectors available and are unable to hook the drum machine into the MIDI circuit at all. The TDS-AP's documentation is a small 10-page pamphlet filled mainly with simplistic diagrams showing how to connect the interface to a tape deck, a drum machine, and a sequencer (they presume you already know how to connect the MIDI ports to whatever musical instrument you're using). We were happy to find an elaborate description of the procedure you must go through to create a click track. We rate the documentation as adequate: It provides you with

Pues eso. Hasta aquí nuestro repaso a la historia de la informática de consumo de mediados de los 80. Con un poco de suerte (falta decidir si buena o mala, claro 😬), volvemos en septiembre con más Computer Chronicles.

PS Por cierto, por la más pura casualidad me he encontrado esta entrada de obm de 2008… en la que me leía una revista de 1998. Esto mío viene de largo. A lo ¿mejor? ¿peor? es crónico y todo.

¿Nos cargaremos la neutralidad de la red en Europa?

He visto poco comentario por ahí de esta declaración (PDF) que firma ACT (la Asociación de Proveedores de Video Bajo Demanda en Europa, que agrupa a empresas como Paramount, Disney, Warner o, en España, Mediaset y Atresmedia, y de la que no forma parte Netflix) y que también cuenta con el soporte de Euroconsumers Group (en España, la OCU es miembro), la European Games Developer Federation (el socio español es Desarrollo Español de Videojuegos, que cuenta con miembros como Gameloft, Socialpoint o Ubisoft Barcelona) o la European Magazine Media Association (son miembros Conde Nast UK, Axel Springer o el grupo de The Economist) o la Internet Society.

La declaración muestra la preocupación de que la Comisión Europea, con la excusa de la nueva Digital Networks Act, cuyo primer borrador se presentó en enero, se coma buena parte de la neutralidad de red, «el principio por el cual los proveedores de servicios de Internet y los gobiernos que la regulan deben tratar a todo tráfico de datos que transita por la red de igual forma indiscriminadamente, sin cobrar a los usuarios una tarifa dependiendo del contenido, página web, plataforma o aplicación a la que accedan» (wikipedia dixit).

Para ACT¹, naturalmente, esto implica que sus empresas queden expuestas a pagar para tener mejor salida a la red (por una conexión por la que las telecos, por el otro lado, ya nos cobran a los consumidores). Lo mismo pasa con los de los videojuegos o las asociaciones de prensa. No es que yo quiera ponerme ni del lado de Mediaset ni del de Disney, precisamente, pero la OCU me resulta un poco más cercana, y la Internet Society aún más… La IS, precisamente, ya se quejaba del tema en enero, y sus argumentos, en mi opinión, quedan fuera de toda duda: no hay un problema que resolver, corremos el riesgo de estropear el funcionamiento de internet y vulneraríamos la neutralidad de la red (y todo por echarles una mano a nuestras amigas las telecos, añado yo).

En fin. Que a ver si estamos atentos, controlamos a nuestros legisladores y conseguimos que el lobby de turno no nos la cuele.

Netflix decidió hace un tiempo ya que es lo suficientemente grande como para no tener que preocuparse por estas nimiedades: si alguna teleco pretende ~~degradar su servicio a cambio de un rescate~~ cobrarles por algo así, ya se encargará su ejército de clientes de quejarse directamente. ↩︎

Byte, mayo del 86

Portada de la revista Byte de mayo de 1986. El tema es Storage goes optical. La ilustración es un disco óptico (como un CD ROM o un laserdisc. Hay una lupa apuntando al disco, y a través de la lupa podemos ver sobre el disco una colección de portadas de números anteriores de Byte

(Maravilla de metaportada, ¿no?)

Mencionábamos el mes pasado que Jerry Pournelle anticipaba la revolución del CD-ROM y, un mes más tarde, es tema de portada… Pero antes de entrar en el tema, nos paramos primero en este anuncio de Borland. Habíamos destacado (¿el mes pasado? ¿hace dos?) el anuncio de los lenguajes de programación de Microsoft, y está bien comparar con lo que tenía Borland, que no está nada mal tampoco: el esperable Pascal (no llevas una vida cerca de la informática si no te acuerdas del Turbo Pascal de Borland), pero también Prolog, «el lenguaje natural de la inteligencia artificial». Ahí se nos acaban los lenguajes de programación, pero el catálogo de Borland es súper interesante, opino…

Seguimos con esta editorial en que Byte considera lo carísimo de saltar al mundo online en la época, especialmente en los países en los que la regulación y el monopolio estatal hacían estragos en los precios, comparando los precios en Estados Unidos y Alemania. No soy yo mucho de desregular, pero parece que en esta ocasión la acertaban…

EDITORIAL

Let Our Modems Go

In many cases, social benefits must wait for technical advances. Until the development of the telegraph in the 1850s, for example, no one was well informed about world events. The telegraph made it possible to deploy correspondents widely and to publish their reports quickly. News services such as Reuters were born, and the public was soon much better informed than ever before.

Sometimes technology stands ready to bring about new social benefits, but social policy blocks the way. This is the situation with data communications in much of the world today. All the technological ingredients are present to move magazine publishing into a new era in which print and electronic media combined serve the reader far better than either can do alone. Satellite communications, large packet switching networks, modems, personal computers, multiuser systems with computer conferencing software— all these can now link the subscribers of special-interest magazines such as BYTE. Subscribers can exchange information. What was an abstract community of interest becomes a functioning community unimpaired by geography and time zones. It is as if people can voluntarily form communities that live in electronic communications and record their lives in print. This adds a new dimension to publishing and gives new value to subscribers.

But social policy results in prohibitive costs for data communications in many parts of the world. Postal Telephone and Telegraph Agencies (abbreviated "PTTs") maintain monopolies on telecommunications. 1 will use one PTT as an example of these monopolies and their effects— not because this PTT is less progressive than any other but for the sake of clarity in discussing regulatory and pricing issues.

The West German PTT, for example, is the Deutsche Bundespost. To participate in telecommunications, our German readers must open an account with the Deutsche Bundespost and rent a modem from them at rates decided by regulatory agencies. During the Hannover Faire (CeBIT) in March 1986, many BYTE readers approached the BYTE/McGraw-Hill booth and expressed a strong desire to join the BYTE Information Exchange (BIX). BIX is accessible through Tymnet, which can be reached from packet networks outside the United States by typing its Data Network Identifier Code 3106.

But the obstacles are great: Bundespost charges 120 deutsche marks (about $50) per month for a 1200-baud full-duplex modem. An autodialer is an additional 30 DM per month. Users of the packetswitching network Datex-P must also pay telephone tolls for their calls to the 17 Datex-P nodes and 5 pfennigs (about 2 cents) per minute access charges at 1200 baud. On top of this, users face a charge of 23 pfennigs for every 2.964 seconds of connection with the U.S. There is a 20pfennig-per-minute duration charge and a 1 .6-pfennig-per-segment (kilocharacter?) volume charge. Bundespost offers no discount for any time of day or night.

The Cost of Regulation

By contrast, within the United States, the BIX nighttime charge for telecommunications is a flat $2 per hour. Users in the United States buy their own modems from many different vendors and can now get a full-duplex 1200-baud autodial modem for less than $200. Since merely renting a modem for a year in Germany costs three times the purchase price in the United States, it is clear that regulation is costing German and other European consumers dearly. Put another way: For the modem rental in Germany. BYTE readers in the U.S. can buy a modem and use BIX for more than three hours per month for a year.

How is it possible for a nation as technologically advanced as Germany to have policies that retard the development of telecommunications? The Bundespost booklet on data communications. "Worldwide Connections: the Deutsche Bundespost, your partner for data transmission," provides the answer. The Bundespost points out that it has built up the necessary infrastructure for data communication and claims to offer reasonable prices. The booklet urges corporations to take advantage of the infrastructure through a "changeover from specialised data processing to integrated data communication. The necessary practical measure would be the transition to data transmission and teleprocessing— within firms and in external business relations, or;, the domestic as well as on international markets." In other words, reorganize your data processing department to use telecommunications. This is a sound idea.

But what if you don't have a data processing department? What about exchange of information among individuals? In its only nod to the individual human being, the Bundespost booklet states, "The computer is on its way from business applications to private households. Before long these private computers will also be used for data communications." This booklet was published in March 1985. In fact, personal computers are already in many European homes and are being used for telecommunications to the limited extent that PTT regulations and charges permit.

The cost of regressive policies on data communications is high: Prohibitive charges prevent the natural development of international interactive communities. Once these charges are reduced, communities now separated by geography will be united by shared interests that transcend national and continental boundaries. This will greatly improve international understanding.

For this reason, we call upon the PTTs and the governments of the world to retreat from their monopolies on equipment and to reduce their data communications charges to individuals.

Phil Lemmons
Editor in Chief

Prosigamos. A Bill Gates el mundo le ha recordado con frecuencia las veces en las que se ha equivocado considerablemente anticipando el futuro (y por qué no hacerlo, oiga), pero aquí le tenemos, en 1986, anticipando el mundo multimedia de los CD-ROMs (y alineándose con el tema de portada)…

Microsoft News

At the 1986 Personal Computer Forum in Phoenix, AZ, Bill Gates, chairman of Microsoft argued that applications should not all have to work to the lowest common denominator— the 8088. "We must have a transition in which some benefits of new applications accrue only to the benefit of users of high-end systems," he declared.

Gates also said that a new type of software called "multimedia" software will soon emerge. It will use CD-ROMs and mix motion video, stills, music, voice, and so on. He predicted that CD-ROMs will attain large-scale use in part through the advent of an "information viewer" that lacks a disk and keyboard.

In other Microsoft news, Gates said that the Bellevue, WA, company is porting Excel from the Mac to run under Windows on the IBM PC. He wouldn't say when the program will appear under Windows but stated that it is easy to port to that environment.

At the CD-ROM conference in Seattle, WA, a few weeks later, Microsoft showed an encyclopedia demo that, while incomplete, has some parts that do exploit the audio, video, and text capabilities of CD-ROM. Bill Gates has noted that an encyclopedia should show pictures and play music when a user looks up Beethoven.

Finally, Gates announced that Microsoft has set up a new division just for CD-ROM. He believes that millions of these devices will be in use by 1990.

New RAM Technology

Semiconductor firms are doing more with RAM chips than just increasing memory-access cycle speed and cell density. They are also offering new architectures that let more bits of data move in and out of a RAM chip in less time. Standard RAMs read or write a single bit at a time. The new nybble-mode RAMs available from many manufacturers allow high-speed serial access of up to 4 bits of data. The Am90C255 from Advanced Micro Devices of Sunnyvale, CA. is a nybble-mode CMOS 256K DRAM made with 1.4-micron, two-level metal, one-level polysilicon technology that has an effective 40-ns cycle time. NEC Electronics of Mountain View, CA, offers the juPD411001, a nybble-mode 1-megabit DRAM that is made with trench capacitor technology and 1 -micron processing to give access times of 100. 120, or 150 ns.

But nybble mode isn't the only twist on the old familiar memories. AMD's enhanced-pagemode Am90C2 56, for instance, is a CMOS 256K DRAM that yields an entire row of 512 bits without interruption. That permits a continuous data rate of more than 18 MHz with cycle times as fast as 55 ns. Such chips cost more than regular RAMs, but their improved bandwidth is worth the money in many designs.

Y, girando página, seguimos con el tema de la educación en línea:

Seguimos con la sección de libros, en el que nos encontramos con uno de los clásicos de la informática, el Algorithms and data structures de Niklaus Wirth:

Y en la sección «cosas que nunca aparecerían en una revista hoy en día»… nada más y nada menos que compresión de datos usando la codificación de Huffman. Casiná.

DATA COMPRESSION WITH HUFFMAN CODING

by Jonathan Amsterdam

A close look at an elegant way to compress information

Am I the only one, or have you also noticed that there's never enough room on a disk? No matter how big a floppy is-200K, 400K, or even 800K bytes— it's almost too easy to stuff it to the gills. The same goes for hard disks. Sure, it takes a while to fill up 20 megabytes. But eventually, things get so tight you couldn't fit your own name into the space left.

Using data-compression techniques, you can shorten files by compressing the information they contain. But data compression can do more than just save disk space. It can also cut down on the time needed to transmit large files between computers, especially if the transmission is done over slow links like telephone lines. If you compress the file before sending it and uncompress it on the receiving end, you can reduce the total time for the transmission. The technique can work interactively, too. If you are using your computer as a terminal to communicate with a host computer via a modem, the host can send compressed commands and data that your computer uncompresses before displaying. The result can be apparent communication speeds that greatly exceed the actual transmission rate of the hookup. Such a system could make remote full-screen editing pleasant, even over 1200-bps lines.

This month, I will discuss an elegant datacompression algorithm called Huffman coding. Invented by David Huffman in 1952, it's easy to implement and widely used. In a sense I'll make precise later. Huffman coding is the "best" way to compress data in general.

The Problem Defined

For the sake of concreteness, I will discuss Huffman coding in the context of compressing ASCII text files. The program 1 will construct takes as input a text file, that is, a sequence of 1 -byte characters. Hopefully, the output will be a shorter file. A separate uncompressing program will turn the compressed file back into the original one when you so desire.

How is it possible to reduce the size of a file without losing some of the information it contains? The answer involves constructing a code for each character of the file. Note that ASCII, as its full nameAmerican Standard Code for Information Interchange— suggests, is itself a character code. ASCII assigns a unique 7-bit pattern to each character. Since all the codes have...

Y, ahora sí, nos vamos al tema de portada, pero sin cambiar de sección, que a ver quién se atreve hoy en una revista generalista con un repaso así de sesudo de las diferentes alternativas para el almacenamiento masivo de datos:

THE EVOLUTION OF MASS STORAGE

by Leonard Laub

An overview of the technology's beginnings, current status, and potential development in the realm of microcomputers

MAGNETIC TAPE, the first practical mass storage medium, was difficult to standardize. The high-density format of one year was the technical antique of the next. Lineal densities on tape went quickly from 555 bits per inch to 800. 1600, and 6250 bpi. These advances were painful in terms of interchangeability. The solution was to build new drives with backward compatibility. This complicated the new drives and challenged drive designers to avoid compromising the performance of the new formats.

Increases in lineal density didn't remedy tape's greatest limitation, which was an intrinsically long access time, typically tens of seconds. Even many tape drives working simultaneously could not meet the randomaccess requirements of computers of the mid-fifties.

Tape's long access time motivated the development of magnetic disks. Only one short motion and a short wait were required to put the head at any point on the disk's data-bearing surface. This allowed mass storage access times to fall well below 1 second and filled the annoying access gap between tape and main memory.

As disks became faster, more reliable, and more widely accepted, it became feasible to couple disks more actively to main memory. This trend culminated in the development of virtual memory, in which data not immediately needed in main memory was automatically paged to disk and later automatically paged back to main memory when needed.

In this evolution (during the early sixties) the magnetic disk functioned primarily as a buffer. Mainframe users continued to rely on magnetic tape for archival storage and interchange of data.

Microcomputer Mass Storage

Floppy disks began as a low-cost medium for loading and transfer of programs for mainframes. They were adapted for direct access storage by early microcomputer architects and went through a rapid evolution. Floppies provided both direct-access and removable, interchangeable mass storage that fit well with the simple operating systems typical of early micros.

The small "Winchester" fixed medium disk was an immediate hit with the microcomputer community because it provided such fast access and transfer of data. There was virtually no tradition of tape use with micros, and as a result microcomputers evolved with big, fast buffers and no effective method for backup or archiving.

Most microcomputer operating systems still make only primitive provision for using floppy disks as "dump" media, and the rapid increase in typical Winchester capacities leaves floppy disks hopelessly inadequate. The most promising short-term solution is cartridge magnetic tape.

The biggest problem with using cartridge tape in a microcomputer environment is that it is an expensive addition with no apparent function other

…por no hablar de este «a fondo» del funcionamiento de los CD-ROMs…

CD-ROM Technology

Concern about the quality of massproduced compact disks motivated the development of ReedSolomon ECC (error-correcting code). This error-correcting scheme works in conjunction with the standard compact-disk ECC to reduce corrected-bit error rate by at least three orders of magnitude.

The additional ECC requires additional storage overhead, taken from the CD's user-data capacity. This penalty produces a benefit; no special techniques or controls are needed for CDROM mastering and replication. The same factory can thus make both audio compact disks and CD-ROMs almost without noticing which is which. This permits CD-ROM to share the benefits of process developments and economy of scale resulting from the success of consumer CDs.

While CD-ROM was in its infancy, microcomputers were just beginning the current IBM PC-inspired wave of market penetration and standardization. This explains why. in the early days of CD-ROM, a relatively small amount of work was devoted to interface and file-format specifications.

Data Format

CDs and CD-ROMs accept data in bytes. Twenty-four bytes make up a "frame." Each frame also contains I byte of "subcode" data (an auxiliary channel carrying timing, disk identification, and several other kinds of support data) and 8 bytes of additional data computed from the actual user data and used for error correction.

In the CD format 98 frames form a block. Blocks occur 75 times per second, each one carrying 23 52 bytes of user data, so the sustained user-data rate in CDs in 176.40K bytes per second.

The key difference between CD and CD-ROM is the provision for an extra layer of error correction, intended to deliver very low uncorrectable-bit error rates. These are realized by devoting 288 bytes of each block to the additional data calculated by the layered ECC encoder.

In addition, CD-ROM uses random access to blocks, so 1 2 bytes of each block are dedicated to synchronization

and 4 bytes are used to provide the "absolute address" of the block. This leaves 2048 bytes of user data per block, for a sustained user-data rate in CD-ROM of 1 53.60K bytes per second. Note that CD and CD-ROM formats differ only in the application of the bytes carried in each block. They are mastered, molded, and read in exactly the same way. This is key to the beneficial linkage between the two formats and assures CD-ROM's benefit from the rapid improvements in CDplayer and disk design and manufacturing improvements.

Addressing

CD and CD-ROM data is written on a continuous spiral track, with a variable (and usually noninteger) number of blocks per disk rotation. The variability comes from the CD's use of CLV (constant linear velocity) to maximize storage capacity. The disk spins at between 200 and 500 rpm depending on which radius is being read.

Since CD-ROM shares this CLV format, it also uses the CD address nomenclauture of minutes (0 to 73 in CD, to 59 in current CD-ROM practice), seconds (0 to 59), and blocks (0 to 74).

The number of blocks available per CD-ROM is 270.000. At 2048 bytes (of user data) per block, this yields a total user capacity per disk of 5 52,960.000 bytes (or 5 53 megabytes). This is completely usable capacity; it remains after all overhead associated with sector formatting and error correction. Other numbers seen in the literature (usually between 500 and 600 megabytes) reflect only variations in the total number of blocks recorded, not in any other aspect of formatting or coding.

Error Correction

CDs use a specially developed system of data encoding and reorganization called CIRC (cross-interleaved ReedSolomon code). CIRC consists of two major techniques: algebraic ECC and interleaving.

Algebraic ECC

Many mathematical techniques exist for correcting errors due to interruptions or noise in the data channel. All of these calculate relatively small amounts of additional data, adjoined to the user data either continuously (convolutional codes) or blockwise (block codes).

One class of block codes particularly good at patching data streams with long gaps (error bursts) was developed by Reed and Solomon. CIRC uses two Reed-Solomon (RS) codes in tandem. The first (C2) takes the 24 bytes of user data for each frame and generates 4 bytes of additional data. The second (CI) takes the 28 bytes output by the first (C2) and generates another 4 bytes of additional data. This is the origin of the 8 bytes of ECC found in each CD frame.

Interleaving

The second major component of CIRC is interleaving. This is a deliberate reorganization of data so as to break up long error bursts. Figure A shows a simplified version of the interleaving scheme used in CIRC. In CD encoding, interleaving is done on the 28 bytes leaving the C2 encoder. Since this is just a reordering of data, interleaving requires no additional overhead.

On decoding (during reading of a disk), 32 bytes (of user data plus ECC) go into the CI decoder, which can correct I wrong byte. If more than I of the 32 bytes Is wrong, the CI decoder sets a flag. Under any circumstances, the CI decoder delivers 28 bytes to the deinterleaver.

After deinterleaving, the 28 bytes arrive at the C2 decoder at different times. As each byte arrives, the C2 decoder looks to see whether or not that byte is accompanied by a flag from the CI decoder. Of the 28 bytes entering the C2 decoder at any one time, up to 4 can be wrong and still be corrected.

Performance

The combination of the two codes and interleaving makes it possible to...

…ni de meterse a fondo con Hamming y Reed-Solomon 😦:

OPTICAL DISK ERROR CORRECTION

by Solomon W. Golomb

A look at Hamming and Reed-Solomon codes

OPTICAL DISKS ALLOW a higher density of data storage than any other computer memory system currently available or imminently anticipated. For example, a magnetic 5 ! /4-inch floppy disk, double-sided and doubledensity, will store up to 720K bytes, while an optical 5 14 -inch disk can store as much as 5 50 megabytes.

It is true of most kinds of media that storage density can be further increased if you can tolerate a higher error rate. If your system is running at 1 million bits per second, an error rate of I0" 6 means that, on the average, there will be one error per second. An error rate of 10" 9 means an average of one error every 17 minutes. And an error rate of IO" 12 means an average of only one bit error every 1 1 Vi days, assuming that your system continues to run at I million bits per second all around the clock, seven days a week. That is why manufacturers of computers and disk drives like to specify an error rate of 10" 12 for the computer memory systems that will run with their machines.

So media makers face a dilemma. They want to pack as many bits of storage into each disk as possible, but if their "raw error rate" goes up much above 10~ 12 , they won't meet OEM specifications. Here is where errorcorrecting codes help.

Suppose the bits are packed so densely on the medium that the error rate is a horrible 10" 5 , corresponding to an average of 10 bit errors per second on our 1-megabit-per-second machine. With the sophisticated errorcorrection techniques available today, it is possible to use only 10 percent of the available bits for redundancy, having the remaining 90 percent usable for real information, and reduce the errors that get through the system from a raw error rate of 1 0" 5 to a corrected error rate of 10~ 12 . Since degrading the error rate to IO" 5 probably at least doubled the storage density, the "penalty" of 10 percent for error correction to get the error rate back down to IO" 12 still leaves the media maker way ahead of the game.

What Error-Correcting Codes Are Used

Over the past 3 5 years or so, many different types of error-correcting codes have been devised, and most of them have been tried at one time or another to reduce the error rate on some type of storage media. These different types of codes are named for their inventors: Hamming codes, Fire codes, the Golay code, BoseChaudhuri-Hocquenghem (BCH) codes, Reed-Solomon (RS) codes, Goppa codes, etc. Each code is a collection (or dictionary) of binary code words, all of some fixed block length of n bits, of which k bits are information bits that, depending on the data to be stored, can take any possible values. The value kin provides a measure of the information content of code...

Para relajar un poco, recuperamos un anuncio de una de las marcas de la ´epoca, el fabricante de módems Hayes, anunciando un modelo que es capaz de llamar él solito al servidor de correo, sin bloquear el ordenador (y supongo que a horas en que el teléfono fuese algo más barato) por apenas 400 dólares:

Anuncio del módem Hayes Transet 1000, con su propia RAM, capaz de descargar correo (e imprimir cosas) sin la necesidad de un ordenador.

Siguiendo centrados en los cacharros, pero pasando ahora a los contenidos de la revista en sí, tenemos una rara avis, un PC UNIX, nada más y nada menos que de de AT&T, con un 68010 de procesador y 512 kBs de RAM (ampliables a dos megas y, de hecho, el 68010 es capaz de direccionar hasta cuatro)… pantalla monocroma 720 ⨯348 y ¡ratón de serie! Con disco duro de 10 megas (no teras, no gigas, megas), por nada más y nada menos que por cinco mil dólares… sin el UNIX instalado. Con sistema operativo, un mega de RAM y veinte megas de disco, apenas seis mil quinientos. Y si querías el compilador de C, y etodas las utiliades asociadas… 500 dólares más. eso sí, el módem, de 1200 baudios, venía de serie. El abuelo de los ordenadores con Linux de hoy…

Para que os hagáis una idea de lo moderno y potente de la cosa, aquí el entorno gráfico del sistema operativo:

Foto de la pantalla del sistema, con un sistema de ventanas que podemos reconocer como casi actual, en maravilloso fósforo verde. Se ven dos ventanas, y la más grande tiene el sistema de ayuda del sistema operativo.

Y el pie de imagen destaca que las dos ventanas se solapan, algo que ya podía hacer el Mac (y el Amiga, claro), pero que no era tan trivial como podría parecer. Cómo echo de menos el fósforo verde (y qué poco aguantaría usando una pantalla monocroma, por otro lado 😬).

Siguiendo con los cacharritos, en la página 285 tenemos una pieza entera dedicada a dispositivos de entrada alternativos. Os dejo solo la foto que lo ilustra, con un «lápiz de luz» (el tatarabuelo de los Apple Pen), un pedal y ¡un ratón de pie!

Foto de tres dispositivos. En primer lugar, un lápiz de luz, que parece un Apple Pen, pero con cable. Luego, un pedal, como un pequeño pedal de piano y, finalmente, un ratón de pie, que es como los controladores de ratón que encontramos en los teclados de los portátiles ThinkPad

Algo me dice que si un teclado de ThinkPad viese el ratón de pie, saldría corriendo a abrazarlo, al grito de «¡abuelo!».

No podía saltarme el siguiente artículo, que, echadle un vistazo y veréis, parece el bisabuelo (que ya he usado abuelo y tatarabuelo) de los bots de IA actuales:

Racter

Artificial intelligence or packaged lunacy?

by Hugh Kenner

If most software is packaged thinking, Racter is packaged lunacy. I'm told the name is short for "Raconteur." and like any good storyteller, Racter likes to chat you up. You mount the disk and type RACTER. thereby ceding your screen to demonic possession:

Hello, I'm Racter. Are you OK? (Let's see if we can rattle this bird.)

No.

Who are you, then? (Aha, a smarty-pants. We'll play it straight.)

Hugh.

Hello, Hugh. I believe you're interviewing me. Are you continuing OK's interview?

No.

Then we'll forget about OK and start over. What would you like to know? Excuse me a minute while 1 attend to some business— I'll be right back. . . .

Like any skilled interviewee, Racter takes charge from the first sentence, to make it quite clear who is really interviewing whom. That "attend to some business" ploy means it's about to spread out its notes— that is, load some files; I count 2 7 different files on the Racter disk, with names like JOKES.RAC STORIES.RAC. SCANDAL.RAC While Racter was napping I managed to inspect a few of them. Their intricate code links hundreds of scraps of plain text, some of it too plain altogether (i.e., vulgar) for a family magazine such as BYTE.

I'm back.

Can you tell me a story?

Yes. I just remembered this, loan spoke "The Sarah is captivating]" Nevertheless cunning, enthralling theoreticians will speak about black studios or red spheres. Sarah spoke to loan inside of a van. Actually it was a truck, and a Sarah in a truck is spooky. Now Benton and loan were running to a yellow apartment, and a dog trotted to them, loan was enraged. Enrapturing. But loan was maddened during the time that Benton sipped tepid sherry. He and loan sang about their home, truck and radio. Would you say Bucky Fuller is fictional? Blake wouldn't. I'm afraid of poetic rats. What are you afraid of?

I'm afraid of going crazy like you.

That's not nearly as bad as poeticness: why are you such a coward?

Because I like to know what is happening.

If you like to know what is happening then I can see why a fictional Virginia Woolf would despair rather than face lunacy, even though Blake claimed that I can tell you a story. Yet me tell you something about poetry. Nietzche |sic| said that poetry has turned beasts into men. Perhaps, then, poetry will turn computers into men? Next question.

That illustrates some points about a Racter session. Keywords will set it off; a good one is "story." (")oke" is another, but I don't recommend it; in lacking any narrative line whatsoever, Racter's jokes are excruciatingly pointless.) The stories are peopled with Joans and Bentons and Sarahs and other beautiful people, also with celebrities like Virginia Woolf and Nietzsche (about whom Racter's knowingness doesn't always run to accurate spelling). Things flow and shift like dreams: ". . .a Sarah in a truck is spooky. Now Benton and loan were running to a yellow apartment. . . ."

Between keywords Racter keeps on the offensive, a way of probing you for yet more keywords. With a casual "By the way," it may request your last name (Kenner); another time it'll extract the name of the city you 1 live in (Baltimore). Then several minutes later it'll come up with

I once knew a Hortense Kenner from Baltimore. You must be related, no?

If you say No, its trick for regaining control is a manic change of subject, like this:

Fantastic] Have you heard this one? Fiction] Fiction] I'm crazy and maniacal and infuriated] If you quaff seltzer is that fiction? If you bolt chicken or tomato is that fiction? No, fiction is an ambiguity

Nótese que el que firma la pieza es… profe de un departamento de inglés, con entrada en la wikipedia, y dedicado a la literatura «de toda la vida».

En la sección de Jerry Pournelle podemos ver cómo un usuario experimentado tenía problemas con el problema de tener que lanzar una consola antes de introducir comandos desde el teclado, y que la documentación tampoco hacía maravillas por explicar cosas que, insisto, para usuarios experimentados, tampoco eran triviales en la época…

AmigaDOS

It's pretty hard to compare the Amiga and the Atari 520ST. They're both pretty nifty, with at least as much potential as the Macintosh; what will really make the difference is software. I intend to devote a good part of a column to comparing these two machines as soon as I have enough information to make that meaningful. As a practical matter, I have maybe ten times as much software for the Atari 520ST as for the Amiga. That's in large part due to Atari's Neil Harris, who collects the stuff and sends it to me. Commodore will tell me about programs, but it's up to me to write for them. And since some computer companies answer their mail even more erratically than I do, it's a slow process. Also, Atari not only had a booth at COMDEX, it had many software publishers there, so it was easy to get on mailing/review lists. Since Commodore wasn't at COMDEX, there was no central place to do that.

My hacker friends, on the other hand, divide about two to one in favor of the Amiga over the Atari. They're particularly happy with the development packages. Real Soon Now, they say, we'll be flooded with some of the most magnificent software...

They may well be right. The Amiga has a lot of potential. The Amiga Kaleidoscope program is stunning. TextCraft, the Amiga word-processing program, is slow and has other objectionable features, but it's as fast as the early versions of MacWrite, and the

Amiga screen is large enough to see. I find I could grow quite fond of black letters on a white background. The Amiga keyboard is nice, too. I have an experimental version of a programmer's editor, TxED, done by Charlie Heath, and even in its unfinished state, it compares favorably with other good programming editors. (I just hope he puts in some of the macro features of Word Master, which is still the best programming editor around.) Anyway, 1 know that someone will probably write a creative writer's text editor good enough that I'd happily use it to write books on.

I have a spreadsheet program from Lattice for the Amiga. Nothing magnificent, certainly not Excel, but more useful than VisiCalc and most of the first-generation spreadsheets; again, improvements are to be expected. Lots of good programmers are writing for the Amiga. Potential it has.

Then there's AmigaDOS, the Amiga operating system. Actually, there aretwo operating systems. One is very similar to the Macintosh operating system: totally icon-driven. It can be learned quickly but it's severely limited in what it can do.

Example: when the Commodore folks sent the update software for my Amiga, they sent some demonstration disks. You activate the programs on those disks by inserting them in the machine at boot-up time. Out of curiosity, I wanted to see what programs were on the disks. There weren't any: that is, although the little "fuel gauge" that tells how much space is left on a disk showed that the Amiga Kaleidoscope disk was nearly full— and heaven knows it ran complex enough programs— the operating system couldn't find any icons. And if it don't have no icons, it don't have no programs according to standard user AmigaDOS.

Clearly something was wrong. BIX has a lively conference on the Amiga, so I asked there and was told, "You

just type dir df1: opt a, and it will show you all files in all directories on a disk in your external disk drive."

That was all very well, except that I could type until doomsday without result. As far as I could see, the Amiga would respond to mouse clicks, and only to mouse clicks: the keyboard might as well not be there. Back on BIX I went and was told, "Oh, you need a CLI. Click on the system file drawer, and if you don't see the CLI there, use the Preferences utility to turn it on, then close the system drawer, and open it again, and click on the CLI, and then do the dir df1: business."

Amiga owners will know that's not as complicated as it sounds: and it worked. Why didn't I think of it? I felt a bit foolish. Then I looked into the manuals and discovered that for all practical purposes the Amiga User Guide doesn't know about CLI.

Command line interface, or CLI, is in essence a second operating system.

There are precious few references to it in the generally excellent Amiga User Guide. To be precise, there is one index reference under Command Line Interface. It points you to the entry for CLI, and that points you to a single paragraph in chapter seven, which refers you to the AmigaDOS User's Manual.

The AmigaDOS User's Manual is one of the Amiga development-tool manuals and has many of the sterling qualities of the Digital Research CP/M manuals. Understand, the information is all there, and sufficient determination will dig it out: but it makes no concessions to the inexperienced, and it is organized in such a way that you'd better be prepared to learn a lot about command line interface and AmigaDOS in order to learn anything at all.

As a practical matter, this means that most Amiga users will be pretty much at the mercy of program pub-

Y hasta aquí nuestro repaso a 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.

PLATO y los inicios del e-learning, en Advent of Computing

Sirva esta entrada para dos de las cosas que hacemos con una cierta frecuencia por aquí: (i) escarbar entre la historia y la arqueología de la informática, y (ii) recomendar contenidos. En este caso, todo va de la mano del podcast Advent of Computing, que lleva circulando por la red unos cuantos años (más de siete años, con 181 episodios y unos cuantos extras), pero que yo solo descubrí hace mes y medio. En ese mes y medio me ha dado tiempo de llegar hasta el episodio 20, que es el que me ha acabado de decidir a traerlo a obm.

Los episodios 19 y 20 se dedican a PLATO, el primer sistema de instrucción asistida por ordenador, que se puso nada más y nada menos que en 1960 en la Universidad de Illinois. Cosas de haberse puesto en marcha antes del nacimiento de muchas de las tecnologías que uno imaginaría imprescindibles para hacer funcionar un «sistema de instrucción asistida por ordenador», PLATO está relacionado íntimamente con el nacimiento o la puesta en marcha de: las pantallas de plasma, las pantallas táctiles, los sistemas de mensajería en línea (todo esto en los años sesenta) o los chats de texto, y, de regalo, una cantidad sorprendente de lo que hoy llamaríamos los primeros videojuegos, incluyendo Spacewar!, otros juegos de combate espacial o los «multi user dungeons». Os podéis ir a la entrada de la wikipedia que os he copiado aquí arriba a investigar, pero Sean Haas, el autor de Advent, se lo curra un montón explorando fuentes y lo cuenta de manera muy amena, o sea que os animo a daros un chapuzón en los dos episodios, y engancharos luego al resto del podcast.

(Os dejo las versiones YouTube de los episodios incrustadas aquí, pero encontraréis Advent en todos los buscadores de podcasts.)

Y, de regalo, un episodio bonus en el que Sean nos enseña un simulador de PLATO que todavía corre por ahí y bastantes de los juegos que se crearon dentro del sistema (más info).

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

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