[author : Marlin Ouverson] #Edito
Extract : « [...] The response to recent articles on FORTH (DDJ #51 and #52) has been gratifying. There have been both positive and negative comments, all indicating much interest in the FORTH language. From what I hear about the efforts of "FORTHians" (FORTHites? FORTHists?) to organize themselves and to promote their language, we will be hearing more from them in the future.[...] »
TABLE OF CONTENTS
Extract : « H. T. Gordon’s "What FORTH Is?" article is a truly amazing document. It could only have been written by an expert on microprocessor instruction sets who has admittedly "never used an assembler." I get the feeling that we are hearing a weird echo of the point of view of those who argued (circa 1959) that payrolls should continue to be written in machine language. [...]
ZDM Note [...]
I am sorry, however, to read again (and again and again) about certain alleged deficiencies which do not, in fact, detract from the excellent qualities and capabilities of the ZX80. To build a complete computer for less than $200 is quite an engineering feat in itself. [...] »
[author : Ray Duncan] #Listing #Assembly #Diagnostic #Storage
Extract : « The Z-80 Floppy Disk Test is a general purpose utility for testing or initializing a diskette. It requires a Z-80 microprocessor, at least 32 kbytes of random access memory, two flexible disk drives, and the Digital Research CP/M 2.x operating system. Program mode and area of diskette to be tested are controlled from the keyboard. Errors may be audited on the console or the line printer. [...] »
[author : R. A. Hoffman] #Listing #BASIC #Mathematics
Extract : « The need to evaluate polynomials occurs fairly often in scientific programming. For example, in order to plot a polynomial, one has to evaluate it on a large number of points; finding the "zero’s" of a polynomial - say, by the Newton-Raphson method — also entails evaluation of the polynomial many times. Because many difficult functions can be closely approximated by a polynomial (power series expansion), this mathematical form appears often.
In addition to the above, it is often necessary to evaluate the derivatives of a polynomial, which, of course, are polynomials themselves. [...] »
[author : S. B. Bassett] #Listing #Forth #Algorithm
Extract : « While I have no particular claim to being an expert in FORTH programming, I have been using Cap’n Software’s FORTH systems for a couple of years, and have gotten familiar with the operation of figFORTH in its various incarnations.
When I thought about Algorithms, the first thing that occurred to me was Kernighan and Plauger’s Software Tools, since the programming techniques they present are very general, and the functions they perform are quite useful. I got out my copy, re-read it, and found they lend themselves to programming in FORTH very well. [...] »
[author : Robert Hallem] #Listing #Languages #Office
Extract : « I was finishing a fancy maifing list program, with keyed-access files, CRT masks and so forth, when I began to wonder if this might not be overkill. All I really needed was a sequential file of names and addresses, plus some "selection codes" to categorize each entry. Then if I had a program to read the entire file and print labels for those entries with specified codes - that would do the job! [...] »
[author : Arne Rohde] #Listing #BASIC #Assembly #Storage #DataManagement
Extract : « One of the main disadvantages of using cassette tapes as the medium for storing programs and data is the speed with which data can be read and written. The TRS-80 Level II records data on tape at about 500 baud, and can therefore transfer data at about 60 bytes per second. For each block written to tape there is a preamble consisting of 256 bytes of binary zeroes, requiring about 4 seconds to write or read. Since data blocks in BASIC may be a maximum of 256 bytes in length, the preamble will always require at least half of the total data tape processing time. For very short data blocks, the proportion of time spent on the preamble may well be over 90%.
As an example, a two-dimensional array is to be stored on tape. The array consists of 150 x 5 elements, or 750 integer values altogether. Since integer values require two bytes each, the array will require 1500 bytes plus a few for the definition of the array. If 5 elements are written in each tape block, then 150 blocks will require about 600 seconds, or 10 minutes to write. [...] »
[author : Dave Cortesi] #Event #Book #Software #TradeAndLaws
Extract : « Phillip Woellhof Spins Off [...]
Your Whole Summer is Booked Already [...] Southwest Computer Show [...] Saginaw Valley Chapter of DPMA [...] TRS-80 Microcomputer Show [...] National Computer Graphics Association [...]
Computer Industry Trade Expo [...]
National Small Computer Show [...]
Cleverest New Product This Month [...]
An S-100 Do-All Board [...]
An IEEE-488 Bus Driver [...]
A Sideways L.E.D. [...]
A TRS-80 In Orbit? [...]
Useful Reference Cards (8080, 6502) [...]
Cromemco Announces C [...]
A New Version of OASIS [...]
An Improved FORTH for Alpha Micro [...]
HUMBUG? Bah! (SS-50) [...]
An Intriguing Report Writer (Access/80) [...]
Artificial Intelligence Faces The Music [...]
An OEM Wishbook [...]
Directory of Small Computers. It contains 200-odd system descriptions, each thorough, all in the same format for easy comparison, plus 900 company profiles and several vendor directories [...]
A Software Author’s Hopebook [...]
Free Observations of Industry [...]
USC Nerves Itself for the Future [...] »
#Network
Extract : « A computerized bulletin board works just like an ordinary bulletin board system except that instead of paper and thumbtacks it uses a terminal, a computer, and the dial-up telephone network. [...] »
[author : David C. Harris] #Protocol #Networks
Extract : « CNET means Personal Computer NET. The PCNET Project is a group of volunteer computer professionals who are working together to create tools that will accelerate the spread of computer-aided communication. Currently we are concentrating upon three tasks:
(a) arranging the publication of the "Electric Phone Book," a list of Bulletin Board Systems, which appears frequently in Dr. Dobb’s Journal and Recreational Computing,
(b) describing and encouraging the use of the PAN protocol for simple electronic messages, and
(c) creating the PCNET protocol, a powerful set of conventions for computers communicating through the telephone system. This remains our most important and significant activity, and is the topic of this article. We will be publishing more details in the future, particularly in Dr. Dobb’s Journal. [...] »
[author : Barry A. Dobyns] #Software #Programming
Extract : « As computing power gets cheaper and cheaper, we approach the problem of getting useful data into computers in a fashion that is acceptable to the user of the computer. Programmers in particular are going to be under increasingly greater pressure to be more and more productive. Their ability to deal with the problem of getting the solution out of their heads and into the computer will be influenced in great measure by the ease with which they can physically enter data into the machine. Electronic communications, still a budding field in many ways, will have its success measured in part by the ease with which the user can use the system, primarily the ease with which messages can be composed and edited.
With few exceptions, all the programs and data in every computer originated with someone typing to (at) an editor or parser of some sort. This is, I realize, a gross over-simplification, and there are cases which may be considered to be not connected with any editors at all (a friendly IBM 029 card punch, for instance), but the point is well made: in most cases someone uses a text editor of some sort to generate a source program (even DDT can be considered a crude sort of editor for hex), or to enter data, or to generate a program which may, itself, be a restricted type of editor or parser for data entry. A lot of users never consider using any editor other than the one which came with their system for the production of text and programs. Some realize they can improve their efficiency by picking another editor that is better suited to their requirements. Most users have video terminals of one sort of another, yet don’t have an editor that takes advantage of the power available to them. This article is about a class of editors whose popularity is gaining, screen editors, and one of these for CP/M in specific, MINCE ($125.00, Scribble $125.00, AMETHYST $350.00, available from Mark of the Unicorn, P. O. Box 423, Arlington, MA 02174). [...] »