1975 1.07 1977

Vol.1 n°7 (#7) august 1976

Vol.1 n°7 (#7) august 1976

(ddj_1976_08.jpg)

p.3 Personal Computing ’76 — Looks like it’s going to be a great show! (p.193 in reprint volume 1)

p.3 Personal Computing ’76 — Looks like it’s going to be a great show! (p.193 in reprint volume 1)

[author : Jim C. Warren, Jr.] #Event

details of seminars, exhibits, door prizes, etc. planned for the Aug. 28-29 Atlantic City hobby exposition

Extract : «  Up until July 23rd, I wasn’t really all that enthusiastic about Personal Computing ’76, the hobby convention and exposition being held in Atlantic City on August 28th and 29th. I was unexcited, partially because it was way back there on the East Coast, and mostly because I had received no information about explicit programs or events, other than an exhibition of vendors’ goodies. Well, after one lengthy conversation with the Chairman of the convention, John Dilks, all of that has changed. It sounds like it’s going to be great! [...]  »

p.4 1977 NCC Includes Significant Personal Computing Events (p.194 in reprint volume 1)

p.4 1977 NCC Includes Significant Personal Computing Events (p.194 in reprint volume 1)

#Event

Extract : «  The National Computer Conference (NCC) is the largest yearly computer conference and exposition in the U.S. (and probably in the world). It is sponsored by the American Federation of Information Processing Societies (AFIPS), a group group that includes all of the major organizations of U.S. computer professionals. The 1977 NCC will be held in Dallas, June 13-16, 1977. [...]  »

p.5 The Time for Floppy’s is Just About Now! (p.195 in reprint volume 1)

p.5 The Time for Floppy’s is Just About Now! (p.195 in reprint volume 1)

[author : Jim C. Warren, Jr.] #Storage

details of a number of floppy disc subsystems, including one for $995 (in 10-quantity)

Extract : «  Things—most notably, prices—are coming down, fast, in the world of rotating mass storage appropriate for home computers. Prior to this, floppy disc subsystems have either been unavailable for hobby machines, or they have been priced for the industrial consumer (e.g., around $3,000 for a dual-drive system). Things have changed: A hobbyist can now reasonably expect to obtain a complete, assembled, single-drive subsystem for a price in the neighborhood of $1K. Here is the latest information we have:

The best system we know of—and the least expensive—is available from Digital Systems, 1154 Dunsmuir PI., Livermore CA 94550; (415) 443-4078 (ask for Dr. John Torode). This is the same crowd that built Gary Kildall's original floppy interface over two years ago [see "First Word on a Floppy-Disc Operating System," in the April issue of the Journal]. Gary has yet to have problems with the system. Digital Systems also is marketing a low-cost, floppy-based development system to the industrial market. They know what they are doing. What is much more important is that Dr. Kildall's fancy, DEC System 10-like operating system—called CP/M — will run on DS's hardware. CP/M has been in use for over two years in a production and instructional environment. It is well debugged, well documented, and has some significant software subsystems available with it. [...]  »

p.7 Design Contest Offers Head-Per-Track Hard Discs as Prizes (p.197 in reprint volume 1)

p.7 Design Contest Offers Head-Per-Track Hard Discs as Prizes (p.197 in reprint volume 1)

[author : E. Mike Engel] #Event

Extract : «  Gentlepersons: July, 1976

At the request of many computer hobbyists, unhappy with the availability of low-cost, mass memory for permanent program and data storage, we are considering the design of a fast-access, memory kit.

In order to offer you the type of storage that serves your needs, we give you the opportunity to participate in the design. So, open your mind and let us know your ideas.

The major cost item is the engineering time required to design the controller which interfaces the memory and the microprocessor. In order to keep the cost down and to make it interesting and rewarding, we decided to have two contests. One, incorporating hardware, and one for software. [...]  »

p.8 Proposed Hobbyist-Standard* Bus Structure (p.198 in reprint volume 1)

p.8 Proposed Hobbyist-Standard* Bus Structure (p.198 in reprint volume 1)

[author : D. Denny, J. Broom] #Interface

proposal for allocation of the 100 leads on the standard bus (*previously called the Altair/IMSAI bus)

Extract : «  The most important and often overlooked part of an Altair/IMSAI computer is the 100 wire bus structure. This bus structure as defined by MITS has become a "de facto" standard that has encouraged numerous companies to build and market Altair/IMSAI compatible boards, knowing that there are thousands of machines in which to use them. The bus standard has stimulated competition and allowed product specialization; and the result has been to raise the Altair/IMSAI from just a 'hobbyist' tag to a full-fledged computer that is rapidly finding its way into industrial, commercial, and educational applications. For what other computer on the market has such a broad base of hardware manufacturers? [...]  »

p.9 First Rumors of a West Coast Home Computing Faire (p.199 in reprint volume 1)

p.9 First Rumors of a West Coast Home Computing Faire (p.199 in reprint volume 1)

#Event

p.10 The PCM-12: A PDP-8 Look-Alike Well Worth Looking At (p.200 in reprint volume 1)

p.10 The PCM-12: A PDP-8 Look-Alike Well Worth Looking At (p.200 in reprint volume 1)

[author : Jim C. Warren, Jr.] #ComputerKit

Extract : «  PCM, Box 215, San Ramon CA 94583; (415) 837-5400, is marketing a microcomputer kit based on the Intersil 6100 microprocessor. It is a system well worth giving serious consideration. It’s only selling point is that there is a massive amount of systems and applications software in existence for it. And, if you want to use it, instead of simply tinker with it, that’s a major point. The 6100 executes all of the Digital Equipment Corp. PDP-8/E instruction set, except the I/O instructions. Since the "8" has been around for about fifteen years, and is still one of the most popular minicomputers (due almost totally to its software)—there are around 70,000 of them in use—anything that executes a PDP-8 instruction set should be given serious attention. [...]  »

p.11 Z-80... Coming on Strong (p.201 in reprint volume 1)

p.11 Z-80... Coming on Strong (p.201 in reprint volume 1)

[author : Jim C. Warren, Jr.] #ComputerKit

Three kits Under $300 — One includes 2K bytes, Another runs at 4 megahertz

Extract : «  Three groups are (or will be) offering processor boards or microcomputers to hobbyists, based on Zilog’s hot, new µp, the Z-80. They are the Digital Group, TDL, and CroMemCo. The Z-80 has an exciting instruction set that is almost completely upwards compatible with the Intel 8080 (which is, of course, upwards compatible with the Intel 8008). Note: the Z-80 is not pin-for-pin compatible with the 8080; the almost-compatibility only concerns instruction sets. Also note: The Z-80 is being second-sourced by Mostek. [...]  »

p.12 Remember Those Secret Codes You Played With as a Kid? Well... (p.202 in reprint volume 1)

p.12 Remember Those Secret Codes You Played With as a Kid? Well... (p.202 in reprint volume 1)

[author : Mal Stiefel] #Cryptography #Algorithm

details of the National Bureau of Standards encripting/deciphering computer algorithms

Extract : «  (reprinted with permission from, and copyright by, Computerworld , Newton MA 02160)

The National Bureau of Standards (NBS) published a proposed standard in the Federal Register of Aug. 1, 1975 specifying "a mathematical algorithm for encrypting (enciphering) and decrypting (deciphering) binary-coded information” for federal use.

The process is intended to be implemented "in a special-purpose electronic device... designed in such a way that it may be embedded in a computer system or network and provide cryptographic protection to binary-coded data.

"The method of implementation, the control of the cryptographic device and the interface of the device to its associated equipment will depend on the application and environment... Certification of compliance with this standard is the responsibility of the designer and manufacturer of the device." [...]  »

p.16 8080 TECO and a Floating Point Specification (p.206 in reprint volume 1)

p.16 8080 TECO and a Floating Point Specification (p.206 in reprint volume 1)

[author : William E. Severence, Jr.] #Mathematics

Extract : «  Dear Jim, June 23, 1976

Congratulations on the Journal! This approach to software development and to Tiny BASIC in particular is most stimulating.

I would, however, be interested in seeing more support of the 8008-based systems. Presently, I'm running a modified Mark 8 with 15K RAM, 1K ROM operating system, 256 level hardware stack, TVT-I, Suding Calculator interface, ASCII keyboard, National Multiplex Digital Data Recorder (2400 baud) driven by serial-parallel interface of my own design. [...]  »

p.17 6502 software - floating point routines for the 6502 (p.207 in reprint volume 1)

p.17 6502 software - floating point routines for the 6502 (p.207 in reprint volume 1)

[author : Roy Rankin & Steve Wozniak] #Mathematics #Listing #Assembly

Extract : «  Editor’s Note: Although these routines are for the 6502, it would appear that one could generate equivalent routines for most of the "traditional" microprocessors, relatively easily, by following the flow of the algorithms given in the excellent comments included in the program listing. This is particularly true of the transcendental functions which were directly modeled after well-known and proven algorithms, and for which, the comments are relatively machine-independent.

These floating point routines allow 6502 users to perform most of the more popular and desired floating point and transcendental functions, namely:

Natural Log - LOG

Common Log - LOG 10

Exponential - EXP

Floating Add - FADD

Floating Subtract - FSUB

Floating Multiply - FMUL

Floating Divide - FDIV

Convert Floating to Fixed - FIX

Convert Fixed to Floating - FLOAT

[...]  »

p.20 6502 software - monitor for the 6502 (p.210 in reprint volume 1)

p.20 6502 software - monitor for the 6502 (p.210 in reprint volume 1)

[author : Jack Bradshaw] #Listing #Assembly

Extract : «  This listing is a Monitor for the 6502, a-la the Ohio Scientific Model 420. The interrupt vector has been set to use John Zeiglers breakpoint routine. [DDJ, Vol.1, No.3]. His program needs to have a few addresses changed to use this Monitor, but they should be obvious from the subroutine names. [...]  »

p.21 6502 software - Lunar Lander for the 6502 (Assembler-level Game) (p.211 in reprint volume 1)

p.21 6502 software - Lunar Lander for the 6502 (Assembler-level Game) (p.211 in reprint volume 1)

[author : Mark Garetz] #Listing #Assembly #Game

Extract : «  Editor's Note: Normally, we don't like to publish software listings that have no accompanying user documentation. In this case, however, we feel that (1) the program is simple, (2) the listing is very clearly annotated, (3) it's use is self- documenting during execution, and (4) it's presumption of a TIM or DEMON monitor simplifies I/O problems. Please let us know how you feel about it.

Mark assures me that use of this program is super-simple, and fool-proof. He sez:

"It requires a TIM or DEMON monitor starting at 7000H. TIM is available from MOS Technology. DEMON comes with the JOLT from Microcomputer Associates, Box 1167, Cupertino CA 95014; (408) 247-8940.

After placing the program in memory, simply start execution at 0300H. [...]  »

p.26 6800 "Applications software" - Games - Games in Pittman’s 6800 Tiny BASIC (p.216 in reprint volume 1)

p.26 6800 "Applications software" - Games - Games in Pittman’s 6800 Tiny BASIC (p.216 in reprint volume 1)

[author : Carl Kelb] #Listing #BASIC #Game

Extract : «  These games—Stars, Acey-Deucy, Trap, and Slot—were adapted from older versions to Tom Pittman's Tiny BASIC for the 6800. Note: A bell (control-G) was imbedded in the print statements for each *. [...]  »

p.28 6800 "Applications software" - Games - Low-Cost 6800 Systems Software & Games (p.218 in reprint volume 1)

p.28 6800 "Applications software" - Games - Low-Cost 6800 Systems Software & Games (p.218 in reprint volume 1)

[author : Technical Systems Consultants' staff] #Software #Game

Extract : «  TSC is presently involved in the creation of products which are currently in high demand among computer hobbyists and other micro computer users. Up to this time there has been little or no software available for Motorola 6800 based systems other than Monitor programs in ROM. We have developed many programs both useful and fun which allow the system builder to utilize his creation to its fullest extent. [...]  »

p.29 6800 "Applications software" - Games - Shooting Stars for Uiterwyk’s 6800 Micro-BASIC (p.219 in reprint volume 1)

p.29 6800 "Applications software" - Games - Shooting Stars for Uiterwyk’s 6800 Micro-BASIC (p.219 in reprint volume 1)

[author : Mark J. Borgerson] #Listing #BASIC #Game

Extract : «  The game of Shooting Stars was originally published in the September, 1974, issue of People’s Computer Company (under the name of Teaser). It is well described in the May, 1976, Byte, so I'm not going to say much about the game itself here. The primary problem in writing the game in Micro-BASIC is finding a way to group the stars and black holes in the universe into the appropriate galaxies. I have solved this problem using an array of nine numbers which are each the product of several prime factors. [...]  »

p.31 BUGS & FIXES - MINOL: Tiny Trek — More Details & A Correction (p.221 in reprint volume 1)

p.31 BUGS & FIXES - MINOL: Tiny Trek — More Details & A Correction (p.221 in reprint volume 1)

[author : Erik Mueller] #Game #Listing #BASIC

Extract : «  On the space printout, the "K" represents a Klingon ship; the ".", a star; the "B", a starbase; and the "E", the Enterprise. The purpose of the game is to wipe out all the Klingons without the energy dropping below 60. [...]  »

p.32 BUGS & FIXES - MINOL Errata & Praise (p.222 in reprint volume 1)

p.32 BUGS & FIXES - MINOL Errata & Praise (p.222 in reprint volume 1)

[author : Erik T. Mueller , Phillip L. Hansford] #BASIC

p.33 Computer music bibliography (p.223 in reprint volume 1)

p.33 Computer music bibliography (p.223 in reprint volume 1)

[author : John Snell, PCC Research Engineer] #Book #Audio

Extract : «  Digital circuits may be used for controlling analog synthesizers, direct digital synthesis, composing music, analyzing (or tracking several parameters of) traditional musical instruments and the voice, spacial movement of sounds, and processing of musical sounds (filtering, reverberation, choral effects, etc.). I hope the following list of articles and books will help some of you to develop systems which are capable of making music enjoyable even by master musicians. [...]  »

p.36 SMRT Will Hurt (p.226 in reprint volume 1)

p.36 SMRT Will Hurt (p.226 in reprint volume 1)

[author : Leroy Finkel] #Networks

Extract : «  (reprinted from PCC Vol. 4, No. 6)

EDITOR’S NOTE: In general, we are trying to avoid duplicating articles in PCC and DDJ, since our subscribers overlap. This information is sufficiently important, however, that we believe it warrants as widespread publicity as possible.

We believe that in and for the foreseeable future, home computer users will need use of the phone system. They will need it, not for traditional time-sharing, but for accessing large databases with their personal computers.

Since the phone system is the only public carrier that is reasonably available to home computer users, a government- licensed monopoly, it behooves us to assure that it meets our needs with reasonable economy. [...]  »

p.38 Lou Field’s Response to the Editor’s Note to the SCCS (p.228 in reprint volume 1)

p.38 Lou Field’s Response to the Editor’s Note to the SCCS (p.228 in reprint volume 1)

[author : Lou Fields]

p.43 - AND - other hardware & software tidbits, consumer notes, suggestions, questions, etc. (not in reprint volume 1)

p.43 - AND - other hardware & software tidbits, consumer notes, suggestions, questions, etc. (not in reprint volume 1)