[editor : Carl T. Helmers Jr.] [publisher : Virginia Green, Manfred Peshka] [cover : Robert Tinney] #Media
On the cover, artist Robert Tinney has provided a scene depicting the combination of computers and golf handicapping described by Dr. George Haller in his article.
How would you like a PDP-ll/40 in your basement computer room? The price would probably be too high for the typical amateur. But Digital Equipment Corporation also makes the LSI-ll, a microcomputer which implements the PDP-ll/40 instruction set and inherits a wealth of existing PDP-ll software. Turn to Bob Baker's article on the LSI-ll for a summary.
How do you draw a picture on an oscilloscope display? Add a Light Pen as described by Sumner Loomis, and you will be able to add and delete points of light.
When the LIFE program can't figure out a key code, it calls DEFAULT, as described in LIFE Line 3. This issue's LIFE Line 4 specifies the DEFAULT routine used to enter cursor motion control data and numeric data for the KEYBOARD INTERPRETER. As a combined hardware and software system, the LIFE application enters the realm of hardware for the first time with a simple circuit to interface the cursor motion control keyboard and an ASCII keyboard via the same input port.
Wire wrapping is a technique often used to assemble circuits. Turn to Photographic Notes on Wire Wrapping for some pointers for your own custom computer interfaces.
According to tradition, no computer is ever complete without blinking lights. But There's More to Blinking Lights Than Meets the Eye, or the control panel designer's utilitarian motives. This issue provides a few ideas for using simple and inexpensive LED indicators in ways far removed from the traditional control panel application.
In the October BYTE, Richard Gardner commented on the application of personal computers in household situations. In this issue, Ted Lau continues on that theme with an article of "structured speculation" on the Total Kitchen Information System (TKIS).
Computers solve problems, right? One problem which golfers have is calculating handicaps so that duffers can play against pros in the same tournament. In Golf Handicapping (or: Buy a New Peripheral with Money Earned from Your Local Duffers), Dr. George Haller describes a program he concocted to serve as the bas is for a part time business calculating golf handicaps at his country club. For readers with teenage children, this might make a great opportunity for the kids to make some money to help pay for college expenses while learning how to run a business.
Computer systems have many resources which can be used by the person who assembles or modifies the design . One resource which is very important is the memory address space inherent in the design of the computer. Taking Advantage of Memory Address Spaces by James Luscher can provide important improvements in speed and function of your system.
What is style? In his article K or k?, Manfred Peshka describes some notational conventions which apply to BYTE's unique combination of hardware and software information. While the change of these standards is incomplete in this issue, future BYTEs will employ the standard abbreviations and units throughout.
What is one of the most useful peripherals? Why , the television set of course. To use the TV you need an interface. One such interface is the CT-l024 product by SWTPC reviewed by Jim Hogenson.
[author : Carl Helmers] #Edito
Extract : « What a predicament. You've bought this box full of printed circuit boards, transformer iron and integrated circuit silicon. After long hours paying attention to the details of an intricate assembly process it is "done." To the best of your abilities you've verified that the box does what it is supposed to do . Now it's sitting over there on the bench (or living room table (or office desk)) plugged into the AC wall outlet and grinning like a Cheshire cat with a mouth full of LED or TVT teeth. So, now what do you do with it? [...] »
[theme : Hardware] [author : Loomis] #LightPen
Extract : « With only a few components and a few hours of construction you can add a versatile light pen to the oscilloscope graphics interface which has been described in the October 1975 issue of BYTE, page 70 ff.
By holding the light pen to the face of the cathode ray tube (CRT), a point may be added or removed. This eliminates the awkward and time consuming effort required when using a program or manual switches to change the dots on the screen. [...] »
[theme : Applications] [author : Helmers] #Simulation #Algorithm #Electronic
Extract : « Integrating graphics control commands
In LIFE Line 3, the design of the DECODE routine of the LIFE program was presented. DECODE is designed as a table driven mechanism for selecting one of several subroutines which carry out the functions of the LIFE program's KEYBOARD_INTERPRETER. However if you examine table 1 of LIFE Line 3 (see p. 51 of BYTE #4), you will note one conspicuous and intentional lack: There are no routines which process the interactive graphics commands required to set up LIFE patterns on the scope display. [...] »
[theme : Applications] [author : Haller] #Electronic #ListingAssembly8008
Extract : « Almost every golf club keeps a roster of its members with up-to-date golf handicaps. By using these handicaps, the members with varying degrees of skill in the game can play competitively against each other. Many large clubs have gone to semiautomatic computer services with terminals in the clubhouse but most clubs still appoint a handicap committee of members which meets periodically, usually monthly, to calculate each member's handicap. [...] »
[theme : Techniques] [author : Helmers] #Electronic
Extract : « Photo 1: One of the most widely used custom assembly methods in the computer industry is wire wrapping. [...]
Photo 2: The business end of an industrial quality wire wrap tool is the bit and sleeve assembly. [...]
Photo 3: The bit and sleeve may be removed from the typical industrial wrapping too1. [...]
Photo 4: When the trigger has been pulled on a loaded wire wrap gun, the result (hopefully) will be a perfect wrap every time. [...]
Photo 5: To quote the previous caption, "When the trigger has been pulled on a loaded wire wrap gun, the result (hopefully) will be a perfect wrap every time." [...]
Photo 6: Continuing on the theme of less than optimal wrapping results, this picture shows an example of the "impatient wrap." [...]
Photo 7: The length of the coil produced by the wrapping action is a function of the length of bare wire prepared for insertion in the tool. [...]
Photo 8: It is often necessary to connect several wire wrap posts to one electrical bus. The method of accomplishing this is to create a chain of point to point wraps. [...]
Photo 9: The alternative method of chaining which minimizes propagation of changes is illustrated in this photograph. [...] »
[theme : Processors] [author : Baker] #Hardware
Extract : « The Digital Equipment Corporation LSI-11 [...]
Digital Equipment Corporation has a new addition to the microcomputer market. Designated the LSI-11, it is a complete 16 bit microcomputer system on a single 8.5 inch by 10 inch (21.6 cm by 25.4 cm) printed circuit board, combining the instruction set of a PDP-11/40 with an under $1000 price. [...] »
[theme : Problems] [author : Warren] #Experience #Storage
Extract : « Not too long ago, researchers at Stanford Medical Center in California were horrified to discover that several years of data that were stored on magnetic tape had disappeared. The tapes hadn't disappeared, just the data. The discovery was made when they attempted to retrieve some of the data for analysis, but found only "garbage" recorded on the tapes. Even more disturbing was the fact that these tapes were supposed to be ultra reliable. They had been especially developed for storage of important research data and used a fully redundant recording technique for improved reliability. [...] »
[theme : Systems] [author : Lau] #xyzt
Extract : « I want to outline a plan for a total kitchen information system (TKIS) suitable for implementing on a home computer. This outline is the first step in the development of TKISs of arbitrary complexity from the simplest inventory modules to artificial intelligence modules (such as those suggested by Richard Gardner in the October 1975 issue of BYTE). The functional approach used here should allow the reader to plan a complex system using small and manageable, "byte-sized" pieces, or to interface independently developed modules. [...] »
[theme : Reference] [author : Dittrich] #ListingAssembly8080
Extract : « Fred Dittrich, 312 N 8 St (no 2), Columbia MO 65201, supplies this table of op codes for the 8080 instruction set. [...] »
[theme : Applications] [author : Helmers] #Electronic #ListingAssembly8008
Extract : « A blinking light peripheral is an inexpensive, entertaining addition to your computer system. The use of multiple indicator lamps under computer control to produce moving patterns can lead to many hours of creative programming and pleasant amusement. [...] »
[theme : System Design] [author : Luscher] #Electronic #Storage
Extract : « The address space of a computer is the set of addressable data locations provided in the design of its instruction set. A common misconception is to view a computer's address space as the equivalent of the actual memory that the machine has. This point of view is both incorrect and too restrictive for the hobbyist or engineer who is able to modify his machine. [...] »
[theme : System Style] [author : Peshka] #Units
Extract : « The lack of conventions and standards used to abbreviate units of measure, to determine scale of measurements, base of numbers, or mathematical, relational, and logical operators, may occasionally lead to confusion and misunderstandings. There are people who prefer to use such expressions as KB for 1024 bytes, CPS for characters per second, LPM for lines per minute, etc., while others follow different conventions, such as kHz for 1000 hertz, m/s2 for meter per squared second, MB for megabyte (either 1,000,000 or 1,048,576 bytes, depending upon convention), and so on. [...] »
[theme : Review] [author : Hogenson] #Hardware
Extract : « The Southwest Tech CT-1024 is a keyboard to TV interface which displays 16 lines of 32 ASCII characters each on a TV screen. The CT-1024 may be ordeled with a variety of options facilitating easy interface with any computer. The CT-1024 is a welcome compromise between one line LED displays and commercial CRT or hard copy terminals.
Data to be displayed is stored in the form of ASCII coded characters. The display circuitry scans the memory, converts the ASCII codes to 5 by 7 dot matrix characters, and then generates the video signals necessary to reproduce the characters on a TV screen. [...] »
Extract : « 101 BASIC Computer Games, Digital Equipment Corporation. Maynard, Mass. $7.50. [...]
Microprocessors : New Directions for Designers, edited by Edward A. Torrero, 1975. Hayden Book Company, Rochelle Park, New Jersey. $8.95. [...] »