[editor : Carl T. Helmers Jr.] [publisher : Virginia Peschke Londner] [art : Stephen Kruse, Wai Chiu Li, Dorothy Shamonsky, Ellen Shamonsky] [cover : Robert Tinney] #Magazine
#Abstract
About the Cover: Robert Tinney's cover painting this month was inspired by the article, A Theatrical Lighting Graphics Package by William Hemsath, James Seawright, Emmanuel Ghent and Mimi Garrard. While Cyrano soliloquizes, the technical director in the wings keeps track of the lights with the aid of an ingenious graphics system. For more information see page 153.
Last month, Larry Weinstein described the hardware for a programmable character generator. This month, read A Programmable Character Generator Part 2: Software and find out how to program your own special characters for APL programming, music graphics, and so on. page 14
Many computer experimenters buy surplus integrated circuits and have the sometimes tedious job of testing them to see if they work. Mark Thorson offers an elegant way around this problem with A Programmable IC Tester. For relatively little expense, readers can now construct a black box that will put virtually any TTL integrated circuit through its paces quickly and accurately. page 28
Since the introduction of the computer over 30 years ago, we have been forced to use difficult, archaic, near alien languages in order to communicate our wishes to the machine. The development of a system which understands the human language has been slow in coming. Now, Harry Tennant takes the naturally "speaking" machine out of the realm of science fiction and places it right in the lap of the home experimenter. But don't you need a huge machine to do that sort of thing, you protest? Read Natural Language Processing and Small Systems and discover the answer for yourself. page 38
Speech recognition is a key component of any software and hardware design for interesting systems ranging from mobile robots to the interactive and responsive house. To provide some background information on the complexities of the subject, Bill Georgiou has written an article entitled Give an Ear to Your Computer. page 56
Craig A Pearce reviews two programmable calculators from HewlettPackard in The HP-67 and HP-97: Hewlett-Packard's Personal Computers and describes Pinball Wizard, a simulation game he wrote to show off the two units. page 112
Dr William H Norton discusses the potential impact of using microcomputers on computer curricula in Notes on Teaching with Microcomputers. His own experiences using the KIM-1 microprocessor for one of his own courses at Marycrest College, Davenport IA, illustrate their practicality, ease of use, and positive effect. Just as hand calculators revolutionized many types of instruction, so too will micros eventually be used to enhance computer education. page 138
If you would like your computer to compose music for you, read Tom O'Haver's More Music for the 6502. There you will find a simple way to use the complicated sounding technique of first order stochastic control to create your own software sonatas and FIFO fugues. page 140
Would you like to try your hand at speech synthesis on your computer? Steve Ciarcia shows you how to make use of your programmable memory to store and play back digitized speech in Talk to Me! Add a Voice to Your Computer for $35. page 142
An unusual and creative use of microcomputers and video displays is described in A Theatrical Lighting Graphics Package by William Hemsath, James Seawright, Emmanuel Ghent and Mimi Garrard. The authors' system consists of a simple modification to a Processor Technology VDM-1 video display enabling it to simultaneously display five graphs of theatre lighting intensity versus time. page 153
In part 2 of GRAPH: A System for Television Graphics authors John Webster and John Young complete their discussion of a package for use with videotape studio equipment in educational audio visual contexts. page 158
Does your computer have high fiedelity? We don't mean to imply that it lacks character if it doesn't, but as Tom O'Haver shows in his article on Audio Processing with a Microcomputer it is possible to use the capabilities of a personal computer to do some interesting real time audio processing tasks such as reverberation , phlanging and "fuzz." page 166
The fixed disk may soon become a fixture in personal computing, and the ability to store 30 megabytes of memory on line will have a major effect on the way we look at software. Read A Look at Shugart's New Fixed Disk Drive by Senior Editor Chris Morgan. page 174
[author : Carl Helmers] #Edito
Extract : « Once upon a time, I had a telephone conversation with a gentleman whose name I cannot recall. This gentleman was an ardent experimenter, both personally and professionally, and was working on the development of a personal microprocessor system. He knew electronics inside and out, understood the principles of integrated circuits, could predict whether or not a given wire would have to be analyzed as a transmission line or could be treated simply as an interconnection, and knew how to calculate worst case conditions in a circuit. He was getting into microprocessors with the intent of learning enough about computing to enable him to incorporate them into his designs. I must have talked to him shortly after he had begun his project, but certainly before it had been completed to the state of a "working" processor. Given this background, he was able to come up with the statement, "Nobody will ever need more than 1 K bytes of memory for the personal computer. To use any more would indicate a lack of efficiency in the design."
I don't believe that this gentleman still holds this opinion, especially if he has proceeded into the world of programming and using a computer. [...] »
[theme : Software] [author : Weinstein] #Display #Graphics
Extract : « In part 1 last month (page 79), we saw that a programmable memory could be substituted for the character generator read only memory in a video display to create and use special character sets for special computer applications. With a small amount of additional software overhead, it is also possible to control high resolution screen graphics. The techniques for using the programmable character generator are detailed this month, and examples are presented. [...] »
[theme : Test Equipment] [author : Thorson] #Electronic #Diagnostic
Extract : « The high cost of digital components can be significantly reduced by the construction of this simple test instrument. While components of questionable reliability have long been available for a fraction of their value, the experimenter has been unable to take full advantage of them for lack of an adequate means of component testing. This circuit, however, now offers such a means for the rapid and accurate screening of bargain components.
Conventional component testing generally takes the form of either building a prototype circuit and substituting devices until it works, or setting up a rig of lights and switches and testing each gate or flip flop on the chip individually. Although these procedures are sufficient for the construction of trivial circuits employing a small number of integrated circuits, neither is exacting enough nor fast enough to provide the quantity or quality of parts required for a well stocked electronics lab.
The main weakness of both approaches is their failure to check the devices in question under all possible conditions of data. [...] »
[theme : Software Music] [author : O'Haver] #Listing #Assembly #Audio #Book
Extract : « Here is a simple "music" composition and generation program which should provide some fun for the experimentally inclined. In September 1977 BYTE, page 12, Hal Taylor wrote about rules describing the style and structure of computer generated music. He described zeroth order stochastic control, in which the note sequences and durations are completely random. This sort of thing is very easily implemented with a microcomputer, and I suspect many of you have already done so just for fun, but the novelty wears off very quickly. More interesting is first order control, in which the pitches (or more precisely the transitions between pitches, or intervals) and rhythms are governed by some set of rules derived from conventional music (or from mathematics, poetry, etc, according to Hal Taylor). [...]
[...] REFERENCES
Hal Taylor, "Scortos: Implementation of a Music Language," September 1977 BYTE, page 12.
Hal Chamberlin, "A Sampling of Techniques for the Computer Performance of Music," September 1977 BYTE, page 62.
H F Olson, Music, Physics, and Engineering, second edition, Dover, New York, 1967. »
[theme : Speech Synthesis] [author : Ciarcia] #Electronic #Audio #Listing #Assembly
Extract : « [...] What is Digitized Speech?
Digitized speech is simply a standard data acquisition technique with a new definition. For years people have been using computers to scan analog to digital input converters and store the results in memory. Often, in high speed applications such as wind tunnels and nuclear experiments, the sample rates can exceed thousands of samples a second. In cases where the critical event is of short duration, these thousands of samples are stored directly into memory to increase system throughput capabilities. When the event has passed and sampling has stopped, the computer memory contains a record of that event in discretely timed intervals. The stored data is now available to be reduced, analyzed or listed. [...] »
[theme : Video Displays] [author : Hemsath-Seawright-Ghent-Garrard] #Display #Graphics #Electronic
Extract : « We recently developed an 8080 based composition and control system for theatrical lighting. This led us to the need for a way of displaying several time functions at once for examination and editing. Our system already made use of the Processor Technology VDM-1 display module, but the existing character set made it necessary to devote the entire screen to the display of one function in order to have useful resolution. Several functions could of course be superimposed, but this was awkward to program and left much to be desired in visual clarity.
Our first thought was to obtain a special read only memory integrated circuit to replace the control characters in the ASCII set with special characters consisting of a single scan line each, but the expense of this approach seemed impractical. Still, the improvement in resolution with such a character set was just what we needed, so we looked for other ways to modify the VDM-1 circuitry to achieve this; the results are detailed below. [...] »
[theme : Software, Video Graphics] [author : Webster-Young] #Listing #Assembly #Display #Graphics
Extract : « Page Up, Page Down, Page Right and Page Left are some of the more complex subroutines in GRAPH.
Although the VDM-1 contains a scrolling feature which might, at first, seem useful for moving screen information up and down, it operates by changing the orientation of the display on the screen and not by actually moving data in memory. [...] »
[theme : Real Time Applications] [author : O'Haver] #Electronic #Listing #Assembly #Audio #Glossary
Extract : « There is a lot of talk about digital audio processing, but talk is not the same as practical action. As the prices of microprocessor systems and interface devices continue to drop, such applications are sure to become quite common, even among amateurs. This article describes a few of the possibilities of the use of a small low cost microprocessor system for digital processing of audio signals. The effects described involve echo, reverb, fuzz, time delay, phase phlanging, mono-to-enhanced-stereo conversion, and frequency multiplication. These effects could also be quite useful for the experimentally inclined audio enthusiast or music group. [...] »
[theme : Tutorial] [author : Tennant] #Initiation #Linguistic #ArtificialIntelligence
Extract : « What can possibly be said about the use of natural languages, that is the languages people use, with small systems? Where research is done on natural language processing, it is done on the largest computers available. To many computer scientists, the problem of enabling computers to understand natural languages at a reasonable level of competence is beyond the current technology. Consider what are probably the two best natural language processors yet produced by computer scientists: William Woods' LUNAR system which answered questions about rocks brought back from the moon, and Terry Winograd's system which manipulated blocks on a table in response to English commands; both are quite large programs. LUNAR uses one task with 256 K 36 bit words to discover the meaning of the user's query, then uses another task of 256 K words to answer the question. One question could take from three to 20 seconds to answer. Winograd's system did not need the quantity of data that Woods' system needed, but it still required 60 K words of 36 bits to operate in its limited world, consisting of a few blocks on a table. These are just two examples of the many natural language processing projects which have been conducted in recent years. These two (from the early 1970s) and nearly all the others since then share the property that they are large projects done on large machines using large amounts of memory. So what can possibly be said about natural language processing and small systems? [...] »
[theme : Artificial Intelligence] [author : Georgiou] #Electronic #Linguistic #ArtificialIntelligence
Extract : « You pick up the phone and slowly and clearly you pronounce into the microphone: "Number one two one three five five five one two one two verify." You listen as out of the earpiece an awkward but quite intelligible voice repeats what you just have said. Then you say "Dial number." The sounds of dialing follow, then a ringing in the distance and you find yourself talking to the directory assistance operator in Los Angeles. A sequel to 2001 with personal HALs? Not quite. Just plain old 1977 reality. A couple of cards in your computer and some programming can do it. Speech recognition and voice control have come a long way from the "Open Sesame!" of the Arabian tales. Its technical foundations were laid in the 1950s and 1960s. The microprocessor revolution has brought it within the reach of any computer experimenter, opening up a fascinating frontier of voice control and spoken communication between human and machine.
In the following pages I will try to give you an introduction to speech processing and pattern recognition. To demonstrate the principles involved, we will go into some details of the workings of a speech recognizer suitable for a small personal computer. I hope the material to be presented will be enough to give you an idea of what speech recognition is, how it is done and what are its present limitations. It is left to the reader to get excited, read the literature to find more about speech recognition and then buy, borrow or build a recognizer and start using it imaginatively. [...]
[...] REFERENCES
1. Lindgren, Nilo, "Machine Recognition of Human Language," IEEE Spectrum, March and April 1965. A somewhat antique review of the field. This article covers history and some principles in rather nontechnical language.
2. Otten, Klaus, "Approaches to the Machine Recognition of Conversational Speech," Advances in Computers, vol 11, Academic Press, NY, 1971. Easily readable, a less antique review than Lindgren's.
3. White, George, "Speech Recognition: A Tutorial Overview," IEEE Computer, May 1976. A very up to date review, rather technical at points but quite readable.
4. Martin, Thomas: "Practical Applications of Voice Input to Machines," Proceedings of the IEEE, April 1976. The author is president of Threshold Technology and from that vantage point reviews the practical side of speech recognition. »
[theme : Product Review] [author : Pearce] #Review #ComputerPortable #Listing #HP
Extract : « Manufactured by Hewlett-Packard, the HP-97 and its software compatible younger brother the HP-67 are considered by many to be two of the best programmable calculators available.
The HP-97 costs $750, compared with programs $450 for the HP-67. Both feature a full complement of mathematical functions and statistical functions for two sets of variables; additional features include: Reverse Polish Notation; 26 data storage registers (one of which is used for indirect and relative addressing); register arithmetic; 224 pro- gram steps (all fully merged, with no 2 or 3 keystroke instructions); the ability to record programs or data on magnetic cards; a pause feature that opens the keyboard up for user input during a running program; and a smart card reader. [...] »
[theme : Education] [author : Norton] #GeneralQuestions #Education
Extract : « The microcomputer in a classroom is worth a thousand words. The visual demonstrations of computer function and design enable students to grasp ideas that would otherwise have to be abstract verbal constructs. The ability to help student understanding of computers reach a more profound level faster using microcomputer demonstrations opens up many possibilities for the instructor. The newness of microcomputers and probable future applications, such as energy conservation, lend interest to the subject for both student and teacher. [...] »
[theme : Product Description] [author : Morgan] #Overview #Storage
Extract : « OEM can be a confusing term for people new to the personal computing field. It means "Original Equipment Manufacturer" -that is, a company which uses parts and equipment of other manufacturers in order to produce end user equipment for sale to the public.
Recently I had the opportunity to visit an OEM supplier whose name is well-known to the personal computing field: Shugart Associates. Shugart manufactures the floppy and minifloppy disk drives that go into equipment sold by North Star, Apple, PolyMorphics, Smoke Signal Broadcasting, Radio Shack, and many more. They also supply companies that manufacture large computer systems. All told, they claim to manufacture over three quarters of the floppy disk drives on the market, and two thirds of the minifloppies. [...] »
#Association
#Book
Extract : « Z-80 Programming Manual (publication number MK78515) MOSTEK Carrollton TX 75006 300 pages $7.50 [...]
Motorola 6800 Microprocessor Course Technical Training Department Mail Stop 56-773 Motorola Semiconductor 5005 McDowell Rd Phoenix AZ 85003 $25 (7-9 copies); $20 (more than 10) [...] »