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OCTOBER 1979 Volume 4, Number 10 $2.00 in USA/$2.40 in YP
§ a | the small systems joufsnal
A MCGRAW-HILL PUBLIGATION
GENEALOGY
$/09 THE MIGHTY MICR
MC6809 PROCESSOR—20-BIT ADDRESS BUS
DIRECTLY ADDRESSES UP TO 768K OF RAM
Performance and capabilities never before possible are now
available to you in the SWTPC S/09. Computer System.The
$/09 uses the Motorola MC6809 processor, the most
powerful 8-bit general purpose MPU available. It features
more addressing modes than other 8-bit MPU’s and an
optimized consistent instruction set enhanced by powerful
16-bit instructions. This, plus 24 indexing submodes,
promote the use of modern programming techniques like
position independent code, re-entrancy and recursion,
The 20-bit address bus makes possible direct addressing of
up to 768K of memory without any slow or clumsy pro-
cesses such as bank switching. RAM memory is designed
with independent control and array cards for economical
expansion of memory. The DMA and the processor boards
can access memory independently for different tasks.
Multiuser capability is ‘‘built-in’’. No additional hardware
is required to operate additional terminals. A dynamic
memory management system can allocate available RAM in
as small as 4K blocks to the various users or tasks.
The dual-bus motherboard design used in the S/O9 makes
adding I/O ports to the system quick and economical. I/O
address decoding for all I/O slots is supplied with the sys-
tem. All serial I/O cards may be quickly programmed to run
at standard baud rates from 110 to 38,400.
Both multiuser and multitasking/multiuser operating sys-
tems are available for the S/09, BASIC, PASCAL and an
Assembler are immediately available. Editor and Debug
programs are also available for use in system development.
$/09 complete as shown with 128K bytes of RAM memory, one parallel and two serial I/O ports. . .$2,995.00
128K memory expansion card... ........0000 08
Se ee ee ee ee $1,995.00
Circle 356 on inquiry card.
ani ee
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219 W. RHAPSODY
SAN ANTONIO, TEXAS 78216
(512) 344-0241
A
€ Cromemco
Low-cost hard disk computers
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11 megabytes of hard disk and 64 kilobytes of fast RAM In a
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In this new Model Z-2H you get
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You get speed—both in the 4 MHz
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time of only 150 nanoseconds. You
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ae execution time of 1 micro:
get speed in the hard
fia tanuar eit alec memseiiareen
EXPANDABILITY
You get expandability, too. The
high-speed RAM can be expanded to
512 kilobytes if you wish.
And the computer has a full 12-slot
card cage you can use for additional
RAM and interface cards.
BROADEST SOFTWARE SUPPORT
With the Z-2H you also get the
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microcomputer field. Software Cro-
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With all its features the new Z-2H,
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280 BERNARDO AVE., MOUNTAIN VIEW, CA 94040 + (415) 964-7400
Tomorrow's computers now
BYTE October 1979 1
The single card computer
with the features
ee
Circle 80 on inquiry card.
iH a tig
RE,
d
romemco
C80 fe pe oO cha Fg:
‘Specialists in computers and peripherals
280 BERNARDO AVE., MOUNTAIN VIEW, CA 94040 © (415) 964-7400
7 le,
ua ue
ands
: i a
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a
2 BYTE October 1979
a
ee uu it
Foreground
22 TRACING YOUR OWN ROOTS by Stan W Merrill
Genealogical research with a microcomputer
48 POWER HELPS ANALYZE ELECTRIC BILLS by Karen S Wolfe
Determine power usage from appliance ratings
58 SELF-REFRESHING LED GRAPHICS DISPLAY by Steve Ciarcia
Add a digital display to your computer system
12 4. INTERFACING THE S-100 BUS WITH THE INTEL 8255 by David L Condra
Design advice for the person starting out in hardware
1 40 THE XYZ PHENOMENON: Stereoscopic Plotting by Computer by William T Powers
Three-dimensional simulation using optical devices and computer graphics
150 CURVE FITTING WITH YOUR COMPUTER by Fred R Ruckdeschel
A simplified approach to nonlinear regression
196 SPACE GAME by Loring C White
Develop your reflexes with this fast-moving game
200 EASY TO USE HASHING FUNCTION by Don Kinzer
Random symbol distribution aids recall process
page 58
Background
76 PICKING UP THE PIECES by Alfred S Baker
Recovering from disk write errors
90 VARIABLES WHOSE VALUES ARE STRINGS by Dr W D Maurer
String variables can be easy to use
100 IBM COMPATIBLE DISK DRIVES by Jefferson H Harman
Floppy disk sectoring rules
11 3 THE TRS-80 SPEAKS by Tim Gargagliano and Kathryn Fons
Discussion of a vocal output peripheral for the Radio Shack TRS-80
168 LOW-LEVEL PROGRAM OPTIMIZATION: Some Illustrative Cases by James Lewis
How to decrease memory requirements and increase execution speed
186 SOME LAWS OF PERSONAL COMPUTING by Dr T G Lewis
Some unnatural, natural laws SUS
=.
206 BUDGET BUILDING ON A BARE BOARD by Dan S Parker x e
Building computer systems inexpensively A
ores
Nucleus
Editorial, 6 Clubs and Newsletters Directory, 210
Letters, 16 Book Reviews, 242
Technical Forum, 70 Programming Quickies, 246
BYTE News, 107 What's New?, 249
Event Queue, 162 Unclassified Ads, 295
Languages Forum, 174 Reader Service, 296
BYTE’s Bits, 192 BOMB, 296 Cover Art: Genealogy by Tina Mion
BYTE's Bugs, 209
‘BYTE Is published monthly by BYTE Publications inc, 70 Main St, Peterborough NH 03458, a wholly-owned subsidiary of McGraw-Hill, Inc. Address all mail except subscriptions
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Address all editorial correspondence to the editor at the above address. Unacceptable manuscripts will be returned if accompanied by sufficient first class postage. Not
responsible for lost manuscripts or photos. Opinions expressed by the authors are not necessarily those of BYTE. Entire contents copyright © 1979 by BYTE Publications Inc, All
tights reserved.
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ENGLAND.
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October 1979 © BYTE Publications Inc 3
la This BYTE
Putting you in touch with
yourself and improving family
relationships are just two of the
rewards of Tracing Your Own
Roots. The microcomputer is a
perfect companion in the search
for ancestors, Stan W Merrill
introduces some simple ways to
compile your genealogy, and
provides a BASIC program to
involve your computer in the
quest. Page 22
Since your computer is using
precious (and often high priced)
electricity, it seems only right
that it should help analyze your
electric bill. Karen S Wolfe has
developed a program called
Power, and tells us how Power
Helps Analyze Electric Bills.
Page 48
There are a variety of output
devices which could be added
to your computer system. One
About the Cover
This month's cover theme
is provided by an article on
using one’s personal com-
puter for personal genealogy
tasks, “Genealogy” by Tina
Mion. Taking off on this
theme, autumn colors, and
the day of the great pumpkin
at the end of October, artist
Tina Mion has created an
autumnal tree with some
ghostly leaves reflecting a
history of science and
technology.
such device is an LED display.
Steve Ciarcia discusses several
methods of interfacing an LED
display to a computer, and
culminates his discussion with a
Self-Refreshing LED Graphics
Display. Page 58
Disks provide much more
convenient storage than tape.
When write errors occur,
however, they can also be much
more catastrophic, Alfred $
Baker provides a brief descrip-
tion of the two main data file
organizations used on floppy
disks, and also describes a
major problem that can occur
when using one of them. Don't
give up hope. A program is
provided which will aid you
when Picking Up the Pieces.
Page 76
At some time almost every
programmer has wanted to
write a program containing
variables whose values are
strings. Dr W Douglas Maurer
explores two techniques for im-
plementing this task in
Variables Whose Values Are
Strings. Page 90
Jefferson H Harman describes
how IBM Compatible Disk
Drives should perform. Not all
manufacturers who say that
they are IBM compatible mean
fully compatible,
Page 100
The talking computer is now
within the grasp of personal
computer users. Tim
Gargagliano and Kathryn Fons
discuss the Votrax voice syn-
thesizer that is available for the
Radio Shack TRS-80 in The
TRS-80 Speaks: Using BASIC to
Drive a Speech Synthesizer.
Page 113
The Intel 8255 programmable
peripheral interface is a large
scale integration part that
makes interface designing easy.
David L Condra gives advice on
the procedure and includes a
design in Interfacing the 5-100
Bus With the Intel 8255.
Page 124
Using a principle invented
years ago, simulated three-
dimensional graphics may be
produced on a personal com-
puter equipped with a plotter or
similar device. William T
Powers explains the method in
The XYZ Phenomenon.
Page 140
In Curve Fitting With Your
Computer, Fred R Ruckdeschel
describes a simplified method
for obtaining a reasonably
accurate equation as a “best fit”
to a collection of data points.
Page 150
When working with time-
critical or memory-critical pro-
grams, optimization techniques
are often employed. James
Lewis discusses some of these in
his article on Low-level Pro-
gram Optimiz Some Illu-
strative Cases.
Page 168
What is the "Conservation of
Agony?” It is one of the rules of
personal computing proposed
by Dr T G Lewis in his thought
provoking article, Some Laws
of Personal Computing. Read it
and find out why Dr Lewis sug-
gests that “software should be
shared, but hardware should be
replicated,”
Page 186
Loring C White describes a
real-time Space Game which re-
quires you to maneuver a ship
within gun sights and then
destroy the enemy.
Page 196
Hashing is a common method
of handling lists, widely used in
assemblers and compilers for
handling the symbol table. In
this issue Don Kinzer discusses
an Easy to Use Hashing Func-
tion for the 6800 micropro-
cessor. Page 200
Many companies are offering
blank $-100 compatible com-
puter boards. Dan S Parker
describes the substantial savings
that can be achieved by popu-
lating these boards and fol-
lowing some simple guidelines
in Budget Building on a Bare
Board. Page 206
New
Clubs, Newsletters
Charles Freiberg
Publishers Dratting
Virginia Londoner Jon Swanson es
lamson 5
Assocjate Publisher ae uth M Walsh
John € Ha} larion Gagnon
Assistant bom Tes Janet Ames.
Sie Callihan wvid William Hayward
‘Ann Graves
Editorlal Director on
Cari T Helmers dr
tive Editor RouinM Moss
Christopher P "Morgan Anthony J Lockwood
Raymond © A Cote Elen Eingh
n Bingham
Senior Book Editor Production Art
Biaise W Liffick Wai Chiu Li
ors Christine Dixon
Richard § Shutord jolly Carmen LaBossiere
Gre Deborah Porter
Renton Pypearanners Dealer Sales
Bob Braisted chery Aas Ginnie F Boudrieau
Editorial Assistants Te Anne M Baldwin
Gale Britton ‘Sherry McCarthy
fae a oer Manesenagata
Products Editor Mats eaaied
National Advertising
Sales Representatives:
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East
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Officers of McGraw-Hill
Publications Company: Gordon
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Presidents: Daniel A, McMillan,
Jam joddorf; Senior Vice
Presidents: Russell F. Anderson,
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Controller; Thomas H. King,
Manufacturing; Robert L.
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Harold W. MoGraw Jp., President,
Chief Executive Officer and
Chairman of the Board; Robert F,
Landes, Senior Vice President
and Secretary; Ralph J, Webb,
Treasurer.
4 October 1979 © BYTE Publications Inc
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Apple Computer
10260 Bandley Dr.
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Digital Microsystems Inc.
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4448 Piedmont Ave:
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Imsai Mfg. Corporation
14860 Wicks Blvd.
San Leandro, CA 94577
Industrial Micro Systems
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North Star Computer
2547 9th Street
Berkeley, CA 94710
Percom Data
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“).Shugart
6 — October 1979 @ BYTE Publications Inc
Designing the Logic
of the System —
Processor Board Design,
Part 2: Will the Parts Fit on the Board?
by Carl Helmers
This month’s editorial is the latest in a series begun last July describing a new
homebrew 6809 personal computer system. The general backplane design was
presented last month. This month we describe the processor board. Its ideal
features would include:
@ 6809 processor (40 pins) and buffers for external signals.
@ 4 K bytes of 2708 read-only memory for systems software.
© Interrupt flags for lines IO through I7 and peripheral interface adapter
(PIA) port with its interrupt request (IRQ) output tied to the fast inter-
rupt request (FIRQ) input of the processor.
@ If it fits, logic for a primary serial terminal port and connector.
In order to find out whether this is a reasonable allocation of function for
the 4.5 by 9.0 inch area of 1 card in the system, we must systematically
estimate the parts required for each of these segments of the logic. The series of
photographs 1a through 1d show how integrated circuit sockets are used as
markers in the layout of the board space requirements. Each socket has a
sticky paper label attached which is marked with its assigned number. Place-
ment of the socket on an unused prototyping board can be done to help plan
the layout.
Processor Logic Requirements
The processor alone occupies a 40-pin socket, which we will call IC1 since it
is the most important part of the whole computer. In addition, the discrete
components of the clock crystal’s parallel-resonant circuit will conservatively
require the space equivalent of 1 24-pin socket. The buffers required for the
data bus are a pair of DM8833 tristate, bidirectional bus buffers. These are
labeled IC2 and IC3. Three SN74367 tristate drivers provide the buffering for
the 16 address lines, Two sections of 1 of the address buffer chips remain un-
used. These circuits are labeled IC4 through IC6. Another SN74367, which
will be labeled IC7, is required so that 3 of its 6 buffer sections can be used for
the ENABLE, QENABLE, and RW signals of the backplane. These 7 socket
positions plus the 1 24-pin dummy for the clock crystal and related discretes
are shown in position for layout purposes in photo 1a.
In order to provide a uniform connection to the backplane bus, every major
segment of the system will be isolated by a set of bus buffers, such as the
DM8833 parts which are included in the processor section. For the remainder
of the logic on the processor board which will interface to the data bus, a pair
of DM8833 parts labeled IC8 and IC9 will suffice to define a local bus exten-
sion. This local bus extension will service the 2708 read-only memory, the
peripheral interface adapter used for interrupt logic, and the asynchronous
communications interface adapter (ACIA) used for the primary terminal of the
system.
Shugart invented the minifloppy in 1976.
Today there are more than 100,000 of the little drives
in use. That's because users want the affordable
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Shugart packs years of proven floppy
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435 Oakmead Parkway, Sunnyvale, California 94086
‘TM minitloppy Is registered trademark of Shugart Associates
BYTE October 1979 7
(a)
Photo 1: By using a prototyping board as a matrix, it is easy to mark wire-wrap sockets with logical identification numbers and use
them as markers in creating a layout of parts for the board. This series of photographs documents the discussion of the main parts of
the central processor card of the new 6809 homebrew system
(a) The first segment of the layout is the processor itself and its crystal timing standard, data bus extension buffers, and address
buffers.
(b) The second segment of the layout adds 4 read-only memory circuits and 2 socket positions needed to decode and select the indi-
vidual 1024 byte segments (10, 11, 12 and 13).
(c) The third segment of the layout process adds a peripheral port (16) and logic associated with 8 interrupt flags. Miscellaneous
logic at this stage includes decoding of the address of the parallel port.
(d) Finally, the logic of the central processor card is completed with the addition of a communications adapter, 25, and associated
decoding and buffer circuits.
The next logic item to consider is the read-only
memory bank, Four 2708 parts will be used to store up to
4K (4096) bytes total. This memory bank will contain the
resident systems software of the machine, including the
fixed handlers for the 3 different classes of interrupts, the
power on reset routines, etc. We will thus require 4
24-pin sockets for these integrated circuits, IC10, IC11,
IC12 and IC13. In addition to the requirements of the
read-only memory parts, we also require logic to decode
the high-order 6 bits of an address and the read signal.
The read-only memory bank must overlap addresses
FFFO to FFFF in order to provide the vector addresses for
interrupts. Thus decoding logic should be provided to
place this 4 K segment of memory at the upper end of the
memory address space of the 6809, locations F000 to
FFFF. Decoding the high-order 4 bits of addressing can be
done with one half of a 7420 integrated circuit, IC14. The
active-low output of this 7420, along with the RW signal
and the next 2 address bits (A11 and A10) can then be
decoded by a single 7442 integrated circuit, IC15, to pro-
duce a 1 of 4 selection for the active-low chip select lines
of the 2708 read-only memory parts. Photo 1b shows the
tentative layout of the board with the addition of the
read-only memory parts and the local bus extension buf-
fers.
The handling of interrupts in this processor will be pro-
vided by use of a single 6821 peripheral interface adapter
which will be used to read a bank of 8 set-reset flip-flops
found in a pair of SN74279 integrated circuits. The 6821
called 1C16 will require address decoding for its location
8 — October 1979 © BYTE Publications Inc
in memory address space. This leads to the problem of
allocating address space within the whole system, for the
parts needed to decode an address differ depending upon
what address is chosen.
So far, the only address commitment we have made is
the placement of the read-only memory segment at ad-
dresses FOOO to FFFF so that it overlaps the hardware
requirements of interrupt vectors at FFFO to FFFF. Let us
build an address space allocation which takes into ac-
count some of the future expansion possibilities:
E000-->FFFF read-only memory (upper 4 K imple-
mented initially).
Do00--> DFFF 1/O (input/output) and peripheral ad-
dresses (sparsely populated).
0000--> CFFF 52 K main memory space (lower 16 K
implemented initially).
The decision to allocate 8 K bytes for read-only
memory space is a conservative one which allows for the
addition of up to 4 more 2708 sockets on another board.
The 4096 byte address space reserved for I/O will be
more than adequate. The balance of the 64 K address
space is left to the main memory.
Within the 1/O address space of D000 to DFFF, let us
arbitrarily decide that all parallel I/O will be via peri-
pheral interface adapters, and that these parts will be
located at address DOOO and continuing through DOFF.
Since each 6821 requires 4 address locations for its inter-
face, this gives a maximum of 64 such parallel ports in the
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BYTE October 1979 9
system. At the same time, thinking ahead, let us allocate
6850 asynchronous communications adapters to address
locations D100 through D1FF. This reserves 128 logical
slots for potential 6850 parts — again far in excess of
what will actually be implemented. The main reason for
making these allocations start at even hexadecimal digit
boundaries (DO and D1 in the high-order) is to simplify
interpretation of machine code and references to ad-
dresses in the hand-assembled systems software to be
created later. We could just as easily have compressed the
allocations into a contiguous segment of address space
without holes.
After this detour into address space allocation, we can
return to the problem of estimating the parts needed to
decode the 6821 peripheral interface adpater used for the
interrupt flag input. First, we note that the decoding of
the DOxx and Dixx addresses for the 2 peripherals on this
board will share common logic for 7 bits of high-order
information. These 7 bits include 3 which must be logical
1 and 4 which must be logical 0. Two 8-input 7430
NAND gates, IC17 and IC18, will be used to form the
high-order decoding logic, with 1 7404 hex-inverter
package (IC19) used to invert the 4 bits which must be
logical 0. An additional 7404 section will be required for
the DO decode to invert bit line A8. The outputs of the 2
7430 parts are active-low selections of high-order ad-
dresses DOxx and Dixx.
Returning to the 6821 part, IC16, let us allocate its
detail addresses as D000 to D003. The 2 register select
inputs of the circuit will get connected to the low-order
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10 = October 1979 © BYTE Publications Inc Circle 66 on inquiry card.
address lines, AO and Al. We need to verify that all bits,
A7 through A2, are 0 when these addresses are selected:
to do this, logic of another 7404 inverter IC20 and a 7430
8-input NAND gate IC21 is required. The final result is
the definition of 1 chip select input to the 6821 from the
high-order address selection of DO and a second chip
select input from the low-order address selection from
IC21.
With its addresses decoded, the 6821 now talks to the
bus extension of the system, but we have one more item
to consider: the 74279 interrupt flag chips and pull-up
resistors. We will assign the numbers IC22 and IC23 to
the flag registers, and assign the number IC24 to a 16-pin
socket which will be used to hold 8 resistors which tie the
8 interrupt lines (I0-I7) up to +5 V when no input is pre-
sent. Photo 1c shows a layout of the board after all the
sockets connected with the interrupt peripheral interface
adapter have been added, 1C16 through 1C24.
The one remaining device to consider is the addition of
a 6850 asynchronous communications interface adapter
which we will call IC25. This will be the terminal port
through which initialization information will be sent in
an American Standard Code for Information Interchange
(ASCII) encoded form from the primary computer and
mass storage device of the multiple processor system. In
separate tests of the 6809 system, this port can be driven
by a terminal, since the initialization sequences will use
standard ASCII characters as opposed to a more compact
binary form.
The address decoding for this port was begun in earlier
considerations. We have a line decoding the D1 address
of serial ports in the high-order, an output of IC18. With
an asynchronous communications interface adapter, we
have to decode 7 out of 8 low-order bits in order to assign
the necessary 2 addresses. Using addresses D100 and
D101 for this port, we need a single 7430 8-input NAND
gate 1C26 for the low-order selection. The inverted states
of address bits A2 through A7 are shared with the
decoding of the 6821 part discussed earlier, and inversion
of the Al bit can use a spare section from either the 7420
C14 or one of the hex-inverter packages.
Also required for the serial interface is some form of a
socket header for a D connector attached to a cable and
level conversion integrated circuits. Thus IC27 which is
an MC1488 and IC28 which is an MC1489 provide our
level conversion, IC29 is a socket devoted to attachment
of the cable to the D connector. By popping off the plastic
cover on a wire-wrap socket, such as IC29, it is possible
to insert a small (#20 gauge) stranded wire into the con-
tacts of the socket. This wire can then be carefully
soldered so that no bridges to the next pin occur, or every
other pin can be assigned to this I/O function where only
a subset of the 14 or 16 pins is necessary. Photo 2 illus-
trates this point of fabrication by way of an example.
There is one minor detail which still remains with
respect to the communications interface: we need a clock
which can supply a frequency of 16 times the data rate of
19,200 bps, or 307.2 kHz. It turns out that given a 5 MHz
central processor clock source, we come very close to the
desired data rate by simply dividing by 16 to get 312.50
kHz. The error in this frequency is 1.7%, with respect to
the proper clock of 307.20. Will this work? Yes, for the
Text continued on page 14
WH14 Serial Printer
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WH27 Dual Floppy Disk System
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‘WH19 Smart Video Terminal
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ce
WH11A 16-bit Computer
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The powerful 16-bit WH11A Computer (DEC® PDP 11/03 com-
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8” Floppy (DEC RX01 compatible) for vast storage capacity and
immediate access to programs and data. For video output, add
the WH19 Smart Terminal with professional keyboard, direct
cursor addressing and eight user programmable keys. The
WH19is compatible with the DEC VT52 and ANSII Escape Mode.
The WH11A System is ideal for the complex problems of busi-
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Souwore
The WH11A Computer runs all systems and applications soft-
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The WH27's disk operating system was developed in conjunc-
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The disk operating system for the WH89 All-in-One Computer
supports MICROSOFT™ BASIC, MICROSOFT™ FORTRAN and
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Hulmanware
The people who build Heath Data Systems hardware stand be-
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U.S. and at many more locations in Canada and Europe. There’s
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Takes closenlool,
Heath Data Systems are on display at your nearby Byte Shop,
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OEM discounts
They're available and they're generous. Call (616) 982-3361 for
details.
ed 1 STS
Heath Data Systems, Schlumberger Products Corporation
Hilltop Road, St. Joseph, MI 49085
DEC is a registered trademark of Digital Equipment Corporations. C5. 74
Circle 99 on inquiry card.
When you
set your
standards
high,
Pick
ADaisy.
Diablo invented the Daisy Wheel.
Which is why today, more people
pel one of over 100 different Diablo
aisy Wheels when they want print
quality at its finest.
So, the next time you want to
set your standards high, pick our daisy
and youre sure to look your best.
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12 October 1979 © BYTE Publications Inc
(a)
Photo 2: A good technique for interfacing wire-wrap cards with the external world is to
use a socket as a header. Here is an example of how a 14-pin socket has its top cap being
popped off (a). Then (b), it is possible to carefully insert small stranded wires which are
firmly soldered in place and run the wires to the external device. After popping the top,
it is possible to very carefully remove every other pin in order to space out the termin-
ations and help eliminate the possibility of a solder bridge. Here we have taken a 14-pin
socket and wired it with the following pin assignments for an RS-232C female D
connector:
RS-232C pin to Socket header pin
1 < -> 1 chassis ground
2 <- “-> 3 output
3 < “> 8 input
4 < = request to send
5 < “> 8 clear to send
7 <- = 1D signal ground
comments
id pins type
IC1 40 6809 microprocessor
Ic2 16 DM8833 tristate bidirectional buffers DO-D3
IC3. 16 DM8833 tristate bidirectional buffers D4-D7
Ic4 16 74367 tristate buffers AO-A6
Ics 16 74367 tristate buffers A7-A11
IC6 16 74367 tristate buffers A12-A15
\c7 16 74367 tristate buffers ENABLE,QENABLE,RW
Ics 16 DM8833 tristate bidirectional buffers DO-D3 local bus extension
Ico 16 O0M8833 tristate bidirectional buffers D4-D7 local bus extension
IC10 24 = 2708
ICi11 242708
ICi2 24-2708
1013 24.2708
\C14. 14 7420
C15 16-7442
IC16 40 6821
IC17 14. 7430
IC18 14-7430
IC19 14 7404
C20. 14 7404
IC21 14° 7430
read-only memory, FO00-F3FF
read-only memory, F400-F7FF
read-only memory, F800-FBFF
read-only memory, FCOO-FFFF
peripheral interface adpater, D000-D003 interrupt port
high-order decode select for IC16
high-order decode select for IC25
low-order decode fo IC16
IC22. 16 74279 interrupt flag latch, 10-13
IC23. 16 74279 interrupt flag latch, 14-17
1C24. 16 =SKohm resistors for interrupt line pullups
asynchronous communications adapter, D100-D101
low-order decode for IC25
(C27, 14 = MC1488 TTL to RS-232C line drivers
1C28. 14. MC1489 RS-232C to TTL line receivers
C2914 14 pin socket for RS-229° cable termination
1C30 14 7473, divide by 4 for communications clock rate
Table 1: List of integrated circuits for new 6809.
Tinker, Tailor, Soldier, Sailor . . .
Doctor, Lawyer ... the Chieftain’s here.
No matter whether you’re a serious
hobbyist or a serious businessman, the
Chieftain 6800 microcomputer with ca-
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Smoke Signal’s quality-packed
Chieftain I features two 5.25-inch mini-
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tures two 8-inch floppy drives.
Bothmicrocomputers
provide 32K static memory,
two serial I/O ports, a 2 try
MHz processor board, a2K Ls
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wo NM ng
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Every Chieftain is complete with
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And it’s expandable to 64K memory
with up to 2 megabytes floppy disk
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So see your nearest Smoke Signal
dealer, he’ll be glad to show you how to
get your wampum’s worth. Systems
start at $2,595.
O Send information on your Chieftain
microcomputer
C Send name of nearest dealer
Name.
Address
Company
I
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pa
CS
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\ State/Zip
31336 Via Colinas. Westlake Village.
California 91361, (213) 889-9340,
Hail to the Chieftain
Smoke Signal Broadcasting, 31836 Via Colinas, Westlake Village, CA 91861, (213) 889-9340
Circle 328 on inquiry card. BYTE October 1979 13
Circle 224 on inquiry card.
Improve TRS~80
performance
with new DOS*
Enjoy the wizardry of your TRS-80 to its fullest: maximize and
expand all of its magical capabilities with the new DOS+. Just look at
the capabilities you can evoke.
Modifications, corrections, and enhancements to Radio Shack’s
TRS DOS 2.1
© A Basic REFerence command for variables and numbers.
© Asuper-fast machine language RENUM program execu-
table under BASIC.
@ A built in kevboard-debounce routine.
‘© Aprint screen option under DOS or BASIC to your line printer.
Simply press JKL keys.
‘© New copy commands for backup, allows you tocopy from drive
to drive keeping the same filespec.
‘© Execution of DOS commands while in BASIC.
© New BASIC scrolling and invocation commands and more.
© Apparat’s own SUPERZAP, a Hex dump utility to examine or
or modify disk or memory jocations.
© Modified EDITOR ASSEMBLER with Disk /O and new cross
reference feature.
¢ Asuper-fast machine language DISASSEMBLER program.
© ALOAD MODULE for transferring machine tapes to disk.
© Faster disk access.
© Level | ROM relocated in Level i! RAM.
© The capability of storing and retrieving Level I programs on Disk.
@ An improved DISKDUMP program.
© ADIRCHECK program to test a directory & lst/display the
contents in alphabetical order with extensions.
You don't have to pull a rabbit out of a hat ... Send $99 forthe
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14 — October 1979 © BYTE Publications Inc
Text continued from page 10:
total time of 1 character, the error in the last bit sent is
what counts. A character is a sequence of 11 bit times; 1
bit has a width of 1/11th or 9.1% of the total time in-
volved. The worst case of the last stop bit in the 11 bit se-
quence (start bit, 8 data bits, 2 stop bits) will have the full
timing error of 1.7% of the total period for 1 character.
Wecould probably get away with as much as a 5% to 6%
error in the frequency of the data rate clocks.
Thus by providing a 2-bit divider in the form of a 7473
circuit IC30, we get the clock needed for the communica-
tions circuit from the crystal controlled 1.25 MHz
ENABLE output of the processor. It turns out that the
serendipity of the 5 MHz junk box crystals really worked
in planning this system. If it is necessary to use a 4 MHz
crystal for the system because the 6809 will not run 25%
faster than its specification then use of a divisor of 13 in-
stead of 16 produces a data rate of 307.7 kHz which is
only 0.2% off the desired 307.2 kHz rate. In this case of a
4 MHz source, a 74193 would be used instead of a 7473
for IC30, and input to the 74193 would be taken from the
tank circuit through a relatively high-impedance buffer.
This completes the preliminary consideration of the
central processor card design. As can be seen in photo 1d,
the 30 integrated circuits sockets required for this central
processor design fit the space available on the proto-
typing card with room to spare. Table 1 summarizes the
integrated circuit and socket list as it stands now. This
verbal discussion ahead of drawing a diagram of the cir-
cuit is an experiment. In past designs, 1 have jumped right
in to the drawing of a logic diagram. The actual circuit
diagram has not been drawn as of this writing (June 18
1979), and 1 or 2 integrated circuits may be necessary to
provide an additional random logic gate or inverter
beyond those anticipated in this discussion.
In the next installment of this series on building a
homebrew general purpose computer for use as a com-
munications controller, we shall start with a verification
of these design considerations as an actual diagram, then
proceed to discuss construction and testing of this first
card in the system. As emphasized in the earlier com-
ments in this series, the timing of the publication of these
notes depends upon the amount of spare time I have
available to devote to this activity. The intent of this
series is to show our readers how simple it is to assemble
homebrew systems out of standard parts, using design
information which is available in various publications
put out by semiconductor manufacturers. @
Articles Policy
BYTE is continually seeking quality manuscripts written by indi-
viduals who are applying personal computer systems, designing
such systems, or who have knowledge which will prove useful to
our readers, For a more formal description of procedures and
requirements, potential authors should send a large (9 by 12 inch,
30.5 by 22.8 cm), self-addressed envelope, with 28 cents US postage
affixed, to BYTE Author's Guide, 70 Main St, Peterborough NH
03458.
Articles which are accepted are purchased with a rate of up to $50
per magazine page, based on technical quality and suitability for
BYTE's readership. Each month, the authors of the two leading
articles in the reader poll (BYTE's Ongoing Monitor Box or
“BOMB") are presented with bonus checks of $100 and $50. Unso-
licited materials should be accompanied by full name and address,
as well as return postage.
Circle 335 on inquiry card, —a
SSM “BLUE BOARDS”
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But value goes beyond the boards themselves.
It's reflected in the company that stands behind
them. And SSM has been known for unparalleled
customer service since the beginning of the
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With one of the broadest product lines in the
S-100 marketplace, it's likely that SSM has the
board you need. So, if youre looking for value, ask
for the “Blue Boards’ They're available at over Our product line includes CPU, Video,
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mw CRI
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= Qual intensity display
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© Wékey numeric pad with decal
© 16 sp thon key:
* 8.edkt lunction keys
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* Self test mode
* Protect mode
© Block mode
* 80slorable tabbing
* Inseet‘deiete character and line
* Sceolling
* Addressable cursor
* Rhos! of other features. including cursorcontrols
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16
October 1979 © BYTE Publications Inc
ULIRASONIC IRANSUDUCEHKS
LOCATED
Just a short note to ask for a helping
hand and to let you know that your
articles in BYTE are read and enjoyed.
In your article “Building a Computer
Controlled Security System for Your
Home"(March 1979 BYTE, page150) you
showed a circuit for generation and
detection of ultrasonic signals, Would
you be so kind as to note a company or
two that I could contact for transducers?
I have an application for ultrasonics and
need a little help in knowing where to
write,
Thank you for your help, and again 1
enjoy your articles,
Tom Yocom, WAIRTD
21 Bayberry Rd
Acton MA 01720
Author Ciarcia Replies:
The particular transducers used in the
March article are from MASSA in
Hingham MA, I obtained them through
Bullet Electronics, POB 401244E
Garland, TX 75040, (214) 278-3553. I
suggest calling them to determine price
and availability. Since I usually purchase
components in large quantities long
before I actually need them for an arti-
cle, I hesitate to quote a price and a
definite source. The MASSA units had
an output frequency of 23 kHz.
LONG DISTANCE
COMMUNICATION .
I saw your article in the May issue of
BYTE (“Communicate on a Light Beam,”
page 32) and became very interested. I
have an application which requires sen-
ding data up to a kilometer at speeds
from 2000 to 9600 characters per second
(cps). Your descriptions of the fiber
optic cable and the light-emitting diode
(LED) transmission circuits seem to be
ideal, if they are cost effective.
Could you give more details of the
distances which the circuits can drive
and the addresses of the suppliers of the
fiber optic components?
RH Fields
1 Wythegate
Riverside Rd
Staines, Middlesex
United Kingdom
Author Ciarcia Replies:
Realize, of course, that the circuits
presented, while possibly usable in com-
mercial applications, are presented more
to introduce the reader to the concept of
fiber optic communications than solve
any particular application problem.
Their usability in a 1 kilometer data link
depends upon more than just the elec-
tronic parameters of the circuit. The
laser probably can drive such a length,
but cable losses and mechanical/optical
connections are going to be an impor-
tant factor in any success.
When you speak of 9600 cps that is
approximately 100 k bits per second
(bps) and is a reasonable transmission
rate. However, response time of the
receiver electronics is going to be much
more critical than a 10 k bit rate. Given
the length of cable as 1 kilometer, I
would caution you that a certain inten-
sity must be maintained at the ouput to
achieve this response.
Rather than try to reinvent the wheel
or try to second-guess the technical
people who really know the field, I
think you would be better off purchas-
ing a commercial system. The following
isa list of American companies which
deal in fiber optics. I am sure they will
have a cost-effective solution for you:
Corning Glass Works
Telecommunications Dept
Corning, NY 14830
(607) 974-8812
Dupont Co
Plastic Products and Resins Dept
Wilmington, DE 19898
(302) 774-7850
Fiberoptic Cable Corp
POB 1492
Framingham, MA 01701
(617) 875-5530
Galileo Electro-Optics Corp
Galileo Park
Sturbridge, MA 01618
(617) 347-9191
eneral Cable Corp
500 W Putnam Ave
Greenwich, CT 06830
(203) 661-0100
WT
Electro-Optical Products Div
Roanoke, VA 24019
(703) 563-0371
Quartz Products Corp
688 Somerset St
Plainfield, NJ 07061
(201) 757-4545
Times Fiber Communications Inc
358 Hall Ave
Wallingford CT 06492
(203) 265-2361
Valtec Corp
Electro Fiberoptics Div
West Boylston, MA 01583
(617) 835-6083
For further descriptive information on
the use of fiber optics I suggest you refer
to the January 5, 1978 issue of EDN
magazine and an article titled “Designer's
Guide to Fiber Optics."
Text continued on page 18
North Star Horizon-
COMPUTER WITH CLASS
The North Star Horizon computer can be found everywhere
computers are used: business, engineering, home — even the
classroom. Low cost, performance, reliability and software
availability are the obvious reasons for Horizon’s popularity.
But, when a college bookstore orders our BASIC manuals,
we know we have done the job from A to Z.
Don't take our word for it. Read what these instructors have to
say about the North Star Horizon:
“We bought a Horizon not only for its reliability record,
but also because the North Star diskette format is the industry
standard for software exchange. The Horizon is the first computer
we have bought that came on-line as soon as we plugged it in,
and it has been running ever since!”
— Melvin Davidson, Western Washington University,
Bellingham, Washington
“After | gave a ¥2 hour demonstration of the Horizon
to our students, the sign-ups for next term’s class in BASIC
jumped from 18 to 72.”
— Harold Nay, Pleasant Hill HS, Pleasant Hill, California
“With our Horizon we brought 130 kids from knowing
nothing about computers to the point of writing their own Pascal
programs. | also use it to keep track of over 900 student files,
including a weekly updated report card and attendance figures.”
— Armando Picciotto, Kennedy HS, Richmond, California
“The Horizon is the best computer | could find for my class.
It has an almost unlimited amount of software to choose from.
And the dual diskette drives mean that we don’t have to waste
valuable classroom time loading programs, as with computers
using cassette drives.”
— Gary Montonte, Ygnacio Valley HS, Walnut Creek, Calif.
See the Horizon at your local North Star dealer.
Circle 285 on inquiry card.
Northstar
North Star Computers
1440 Fourth Street
Berkeley. Ca 94710
(415) 527-6950 TWX/TELEX 910-366-7001
Text continued: Apple II, uses “V & H” coordinates for
72 border towns to sketch an outline
map of the US,
Phone Company Maps...
In reference to your article on map
generation (“Computer Generated
Maps,” May 1979 BYTE, page 10) the
telephone industry has gridded the US
with a system of vertical and horizontal
coordinators (“V & H's). A discrete set
of four digit “V & H"s for virtually
every city, town and village is listed
Federal Communications Commission
tariffs,
“NV & H" coordinates offer a quick and
simple way to plot maps of American
locations. For example, the program
listing, at right, written for an
Joseph P Garber
36 Sutton Place S
New York NY 10022
64KB MICROPROCESSOR
MEMORIES
@ S-100 - $750.00
@ LSI - $750.00
@ SBC 80/10 - $750.00
@ 6800 - $750.00
CI-S100 — 64K x 8 on asingle board.
Plugs directly into the IMSAI, MITS,
TDL, SOL and most other S-100 Bus
computers. No wait states even with
Z80 at 4Mhz. Addressable in 4K in-
crements. Power requirement 6 watts.
Price $750.00.
Cl-1103 — 8K words to 32K words ina
single option slot. Plugs directly into
LS! 11, LSI 11/2, H11 & PDP 1103.
Addressable in 2K increments up to
128K. 8K x 16 $390.00, 32K x 16 $750.00
qty. one.
Cl-6800 — 16KB to 64KB on a single
board. Plugs directly into Motorola's
EXORcisor and compatible with the
evaluation modules. Addressable in
4K increments up to 64K. 16KB $390.00.
64KB $750.00.
= Cl-8080 — 16KB to 64KB on single
i board. Plugs directly into Intel's MDS
the 800 and SBC 80/10. Addressable in
—— 4K increments up to 64K. 16KB $390.00.
Cl-8080 64K x 8 64KB $750.00
Cl-S100 64K x 8
Tested and burned-in. Full year warranty.
i Chrislin Industries, Inc.
Computer Products Division
31352 Via Colinas * Westlake Village, CA 91361 © 213-991-2254
18 — October 1979 © BYTE Publications Inc Circle 47 on inquiry card.
LT ‘NN HFe +, FN VEC Gm TE
hee BB ott Roe fat yO? TE
22 4 PP
5; Fegan
$555,2378,539
3067 -2813,53
37,3490, 56
353372 3752-51
113,4037,52
74,4871,51
SRB ESS ST
28 2582. 9113.79
i
28 #79149 49283,2
5 BYTE CONVERSION
The “5 Byte Hexadecimal to ASCII
Converter” described by Ashwin L
Doshi (June 1979 BYTE, page 208) will
work on the 8080, but not on the 8085
or Z80. As Doshi points out, the routine
depends on the carry and the auxiliary
carry being reset at the start of the
routine. In practice, the conversion
routine is preceded by an instruction
ANI OFH to mask off the upper 4 bits
so that only the remaining 4 bits of the
byte to be converted are passed to the
routine, In both the 8085 and the Z80,
however, the logical AND instruction
sets this flag. The well-known 6-byte
routine functions properly on both the
8085 and Z80.
Robert G Durnal
POB 68
Junior WV 26275
INFORMATION WANTED
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T hope one of your readers can help
me. Thank you.
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280 Henderson St Apt 7]
Jersey City NJ 07302m
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Tracing Your Own Roots
Tracing your own roots satisfies an
intangible craving that many people
have — a craving to understand your
place in a heritage that was developed
by people who are perhaps more like
yourself (at least genetically) than
any other people on Earth. The pro-
cess involves untangling puzzles that
tax the most intelligent imagination.
Relationships must be deciphered
from other people’s memories and
from bits and pieces of written
records that form a fragile and
sometimes inadequate link between
you and your ancestors. It isa natural
application for a microcomputer.
Doing Genealogy
How does a person go about trac-
ing his or her roots? There are several
steps that make the process simpler.
Some of these steps are enumerated in
the following section.
Step 1. The best place to start
searching for your family is, of
course, at home. You should jot
down on paper or key into the com-
puter all the things that you know (or
think you know) about your
ancestry, then look for family
records, such as Bibles and cor-
About the Author
Stan W Merrill is a partner in Computer
Resource Associates, a Chicago based con-
sulting firm which he recently helped found.
Between times, he is writing his doctoral disser-
tation in sociology at the University of
Chicago, Genealogy is a traditional activity in
his family, and some of his lines have been
traced back several centuries.
22 October 1979 © BYTE Publications Inc
Stan W Merrill
Computer Resource Associates
914 E 6st St
Chicago IL 60637
respondence. Frequently these will
contain useful leads that make it
easier to document facts later on.
Next, contact family members:
parents, siblings, the proverbial
great-great-aunt, and anyone else
who might possess a piece of family
information. It is useful to quiz these
relatives about parents, events, dates,
and places, beginning with those peo-
ple who are closest to you in time,
and working backward.
If other family members are in-
terested, it may be possible to
establish a family organization that
will hold occasional family reunions
and share the fun and work of search-
ing out ancestors. Such an organiza-
tion already exists in many families.
It is not unusual for such contact
with family members to plunge the
new genealogist into the first mean-
ingful contacts with some relatives.
Such contact draws people into
warmer and closer relationship that
is, in itself, a substantial reward for
the effort invested in genealogy.
Step 2. The memories collected
from family members cannot usually
provide adequate proof of the events
recalled, since the human capacity to
remember information accurately is
imperfect. Memories merely provide
hints for where to look for birth, mar-
riage, and death certificates (known
as vital records), or for entries in
church and civil record books that
will document the information. These
documents provide official informa-
tion about particular ancestors, and
also give possible clues about other
ancestors in the chain.
Several sources exist for finding
these documents. Often ancestors will
have resided in a single locality for
several generations. A letter to the
clerk of the political jurisdiction
(county, province, etc) where they
lived, or to the parish cleric in coun-
tries where churches kept the vital
records, will often elicit copies of
desirable information. These places
can be visited in person as well.
A number of institutions collect
and preserve genealogical records on
a national or international basis, and
make these records available to the
public. The institution with what is
undoubtedly the most complete col-
lection is:
The Genealogical Society
Church of Jesus Christ
of Latter Day Saints
50 E North Temple
Salt Lake City UT 84102
You do not have to belong to the
Church of Latter Day Saints in order
to use their genealogical data sources.
While the main library is in Utah,
branch libraries are scattered
throughout the United States and
much of the world. The telephone
number of a unit of the church can be
found in most telephone directories,
and a phone call will produce infor-
mation about the location of the
nearest branch library.
Other excellent sources
genealogical data include:
of
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Central Reference Div
National Archives
Washington DC 20408
Library of Congress
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Newberry Library
60 W Walton St
Chicago IL 60610
New York Public Library
Sth Av and 42nd St
New York NY 10018
This list is not exhaustive, but
writing or visiting one of these places
will help anybody get started. It is
also useful to talk to a reference
librarian at a local library. They will
often know of nearby sources of
genealogical information.
Step 3. It is fairly easy and pleasant
for most people to trace back their
ancestry 3 or 4 generations. But when
a line migrates across an ocean, or
when records become less complete
(as they invariably do when going
further back in time), ingenuity
comes into play. Passenger lists, cen-
suses, and tax lists may provide clues
to the identity of ancestors who can-
not be located in vital records. A
knowledge of history is acquired
while searching for clues about mass
movements in which ancestors may
have participated.
This is where the computer comes
in. To know what is missing becomes
increasingly difficult as the number of
ancestors for whom you have infor-
mation increases. It scarcely needs to
be said that computerizing the
records makes it much simpler to
keep track of the data.
Still more helpful is the use of the
computer to solve puzzles. Suppose,
for instance, that you cannot find any
more family members in a certain
line, but you notice from the output
data that a related family line has
moved to a new locality at about the
same time. You have been given a
hint that the first family line may also
have migrated there, and you can
begin to search for information in the
records of that particular place.
Using the Program
You need not be a genealogical
expert to utilize the program that is
listed here. Item 1 on the program's
menu (table 1) automatically prompts
the user for the most important infor-
mation about each ancestor. (See
listing 1.) This information includes
birth date and place, parentage, mar-
riages, and date and place of death.
The program asks for the sources of
information too, so that the inevi-
table need to check entries will be
easier.
To list the information for any or
all of the names that have been
entered into the file, you can use item
2 on the menu, An example of a
listing for one individual is shown in
listing 2. A person can be located by
name or by number. Because it is
possible for there to be more than one
individual in the file with the same
name, you should make certain that
the person listed is the correct one,
The program as now written will not
search beyond the first occurrence of
a name unless the all option is
selected. When all is typed in
response to the prompt, the
subroutine will read sequentially
through all of the records in the file.
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24 =~ October 1979 © BYTE Publications Inc
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In addition to listing file entries,
menu item 2 will revise entries. If a
revision is made because new infor-
mation has been found, simply enter
the number (or name) of the person
for whom the revisions are to be
made, and then select the type of
information that is to be updated.
The revision subroutines are docu-
ment oriented, that is, each asks for
all of the information that is com-
monly found on a particular vital
record. For example, the marriage
revision subroutine requests the date
of marriage, the spouse’s name, the
place where the marriage was per-
formed, and the source from which
because all of these items are found
on a marriage certificate. The docu-
ment orientation of the revision
routines suits the genealogist’s situa-
tion well, for the need to update
information about an ancestor will
usually arise from the discovery of a
new document.
If you wish to revise an error that
was made while entering information
the first time, you should first finish
entering all of the information
requested by the program. The com-
puter will then prompt for changes by
going back to the original menu.
Item 2 will also generate blank
data-collection forms which can be
enter into the computer. This is done
by putting a special symbol in the
data fields for every relevant name,
PLEASE ENTER THE NUMBER OF THE
PROCEDURE YOU WANT:
(1) ENTER INFORMATION
(2) READ OR REVISE INFORMATION
(3) LIST PEDIGREE
(4) END THE PROGRAM
?
Table 1: The genealogy program prompts
the user for a specific use. The user can
enter and modify information, list a
son's pedigree for 4 generations, or fi
the information was obtained,
TASK: ADD GENEALOGICAL INFORMATION TO THE FILE
WHAT IS THE PERSON’S NAME?
(USE MAIDEN NAME WHERE APPROPRIATE)
2 THOMAS MERRILL
TO PREVENT THOMAS MERRILL
FROM BEING CONFUSED WITH SOMEONE ELSE
WHO MAY HAVE A SIMILAR NAME, HE/SHE.
SHOULD HAVE A UNIQUE NUMBER IN THIS FILE.
HAS A NUMBER ALREADY BFEN ASSIGNED?
7 YES
PLEASE ENTER THE NUMRER:
14
I WILL ASK YOU FOR SOME DATES.
PLEASE ENTER DATES IN THE FOLLOWING
FORMAT: DAY MONTH YRAR
EXAMPLE: 23 APRIJ. 1949
IF YOU DON’T KNOW A DATE, ENTER ‘UNKNOWN’.
WHEN WAS THOMAS MERRILL
2? 20 NOVEMBER 1715
BORN (DA MO YR)?
WHERE WAS HE/SHE BORN?
2 HARTFORD CONNECTICUT
WHAT WAS THOMAS MFRRILL *S FATHER’S NAME?
(IF YOU DON’T KNOW, ENTER ‘UNKNOWN’ )
? ABEL MERRILL
DOES ABEL MERRILL
7”
ALREADY HAVE A NUMBER?
PLEASE ENTER HIS NUMBER:
215
WHAT WAS THOMAS MERRILL. “S MOTHER’S NAME?
(USE MAIDEN NAME IF POSSIBLE. IF YOU
DON’T KNOW HER NAME, ENTER “UNKNOWN” )
? MEHITABLE FASTON
used for gathering information to
the program use.
DOES SHE ALREADY HAVE A NUMBER?
y
PLEASE ENTER HER
216
NUMBER :
WHERE DID YOU GET THE INFORMATION AROUT
THOMAS MERRILL “S BIRTH AND PARENTAGE?
(BE SPECIFIC)
2 BIRTH CERTIFICATE 13347A
HOW MANY TIMES WAS THOMAS MFRRILL
(ENTER A DIGIT FROM 0 TO 99)
21
MARRIED?
ENTER A DATE FOR MARRIAGE # 1
2 5 OCTOBER 1755
(DA MO. YR)
WHAT WAS THE SPOUSE’S FULL NAME?
(USE MAIDEN NAME WHERE APPLICABLE)
2 MARTHA WOOD
WHERE WERE THEY MARRIED?
? HARTFORD CONNECTICUT
WHERE DID YOU GET THE INFORMATION AROUT MARRIAGE # 1 ?
2 MARRIAGE CERTIFICATE 3445 B
WHEN DID THOMAS MERRILL DIF (DA MO YR)?
(IF YOU DON’T KNOW, ENTER “UNKNOWN’.
IF HE OR SHE IS STILL LIVING, ENTER “ALTVF.’.)
2:16 SUNE 1814
WHERE DID HE/SHE DIE?
2 HARTFORD CONNECTICUT
WHERE DID YOU GET THE INFORMATION ABOUT HIS/HER DEATH?
? DEATH CERTIFICATE 3988 C
Listing 1; When adding information to the file, the program prompts you for every input and describes the form that it should take. If
an error is made during input, the rest of the information should be completed and the revise option chosen from the main menu upon
completion.
26 — October 1979 © BYTE Publications Inc
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TASK:
DO YOU WISH TO SEARCH BY ‘NAME’ OR BY ‘NUMBER’?
2 NUMBER
PLEASE ENTER THE NUMBER:
214
GENEALOGICAL INFORMATION FOR:
THOMAS MERRILL
NUMBER: 14
BORN: 20 NOVEMBER 1715
BIRTHPLACE: HARTFORD CONNECTICUT
ABEL MFRRILL
MEHITABLE EASTON
MARRIED TO:
MARTHA WOOD
DATE: 5 OCTOBER 1755
PLACE: HARTFORD CONNECTICUT
DEATH DATE: 16 JUNE 1814
PLACE OF DEATH: HARTFORD CONNECTICUT
RECORDS SOURCF:
BIRTH AND PARENTAGE:
DFATH: DEATH CERTIFICATE 3988 C
DO YOU WISH TO CHANGE ANYTHING?
?NO
WOULD YOU CARE TO EXAMINE ANOTHER RECORD?
2 YES
Listing 2: A file may be found and read by either name or
number. When the data has been reviewed, the user may
update the file using the revision command.
place, date, and source in item 1. (A
question mark (?) makes a good sym-
bol for this purpose. The number 0
can be used when the computer
prompts for a number for the indi-
vidual and his parents. The number 1
is a good response when the computer
asks how many times the individual
was married.) Either the special sym-
bol or the number assigned by the
program to the special form is then
used in item 2. The number or symbol
can be requested repeatedly to obtain
as many copies of the form as are
desired.
The program assigns a unique
number to each ancestor so that it can
differentiate between people with the
same name. (My own genealogy con-
tains cases where as many as 3 indi-
viduals have identical names.) Uti-
28 — October 1979 © BYTE Publications Inc
RFAD AND REVISE FILE INFORMATION
(NUMBER:
(NUMBEI
BIRTH CERTIFICATE 13347A
MARRIAGE # 1 :MARRIAGE CERTIFICATE 3445 B
TASK: LIST PEDIGREE.
(ENTER HIS/HER
214
THE SYMBOL ‘F’
THE SYMROL ‘M*
15)
16)
THOMAS MFRRILL.
Fr:ABEL MERRILL
lizing these numbers, the program
will link up any person in the file with
4 generations of his or her ancestors,
thus forming a pedigree chart. An
example of such a pedigree is shown
in listing 3. It is not necessary that
everyone in the file be related. The
program can tell who is related to
whom on the basis of the number
assigned to each person.
Other Ideas
The genealogy program in listing 4
prompts you to enter important
identifying information about your
ancestors. It will print back this infor-
mation and allow revisions. It will
also print a 4 generation pedigree for
any person in the file, but its
usefulness need not stop there: your
own imagination can provide per-
M:MEHITABLE EASTON
FF; JOHN MERRILL
FM:SARAH WATSON
MF; JOHN EASTON
MM: ELIZABETH (EASTON)
FFF:NATHANIEL MERRILL
FFM:SUSANNAH WOLTERTON
FMF: JOHN WATSON
FYM:MARGARET SMITH
WHOSE PEDIGREE WOULD YOU LIKE PRINTED?
NUMBER, PLEASE)
STANDS FOR ‘FATHER
STANDS FOR
“MOTHER ®
PEDIGREE FOR PERSON # 14
(NUMBER: 15 )
(NUMBER: 16 )
(NUMBER: 17 )
(NUMBER: 18 )
(NUMBER: 19 )
(NUMBER: 20 )
(NUMBER: 21 )
(NUMBER: 22 )
(NUMBER: 25 )
(NUMER: 26 }
MFF: JOSEPH EASTON (NUMBER: 27 )
MFM:HANNAH (EASTON ) (NUMBER: 28 }
MMF : UNKNOWN (NUMRER: 0 )
MMM: UNKNOWN (NUMBER: 0 )
Listing 3: When a pedigree is requested, a person's ancestry is traced
back 4 generations. If the ancestry is unknown, then this is stated.
sonal additions. You might wish to
expand the pedigree section to print
out more generations, or write a
subroutine which will sort persons of
the file into nuclear family groups.
You might choose to add a subroutine
to calculate age of death for each
ancestor and average age of death for
subgroups of ancestors. This could
provide insight into the impact of
historical conditions on longevity in
your family, and could even be
applied toward figuring out your own
life expectancy. Along these same
lines, you could add a prompt for
cause of death — an item usually
found on a death certificate. Inspec-
tion of the cause of death for a large
number of ancestors might even alert
you to special diseases that occur
regularly in your family.
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Listing 4: The genealogical program source listing in BASIC Plus 2. Only the input and
output statements will need to be changed to adapt this program to most microcom-
puters with disk storage.
This genealogy program was
written on a DECsystem 2050 at
the University of Chicago, using
00010 PRINT TAR(19); “GENEALOGICAL PROGRAM’ DEC's BASIC Plus 2. The file 1/O
00020 1 (input/output) under BASIC Plus
00030 1 WRITTEN BY STAN W. MERRILL 2 differs from that in many other
00040 1 OF COMPUTER RESOURCE ASSOCIATES
00050 1 914 EAST SIXTY-FIRST STRERT BASICs pra Pkimsie oro.
00060 | CHICAGO, ILLINOIS 60637 revision when running the pro-
00070 | (312) 363-6183 gram under another interpreter or
00080 | ‘compiler. For instance, the MAP
00090 ALLOCATE FILE AND COUNT NUMBER OF CASES ALREADY IN IT statement, which BASIC Plus 2
poli | SET. COUNTERS: uses to allocate space for variables,
00120 PRINT\PRINT\PRINT is unnecessary in some versions of
00130 ON FRROR CO TO 350 BASIC.
00140
MAP GENDATA B,C$(3)=16,D$=25,E$=16,F, G$(3)=25,H$=20, J$=16,K$(3)=20
»L$=20,Q$=25,S$=25,R,T,D1$=40,D2$(3)=40,D3$=40
00150
130
OPEN ‘GEN’ AS FILE #1, SEQUENTIAL VARIABLF, MAP GENDATA, INVALID
To make the program smaller,
reduce the number of prompts.
Another possibility is to break the
program into smaller programs,
00160 LET 12=0 2 4
00170 LET 13=0 ! I3 COUNTS NUMBER OF CASFS IN FILE each of which can be loaded into
00180 ! memory independently as needed.
00190 PRINT "WOULD YOU LIKE A LIST OF THE NAMES CURRENTLY" The 3 major subroutines (labeled
00200 PRINT “IN THE FILE?" “procedure subroutines” in listing
goad be wis 4) are almost self-sufficient, that is,
they can red a: rat
00230 IF W1$="Y" THEN PRINT "THE FILE CONTAINS THE FOLLOWING NAMES ae fam Des ere oe, is he
00240 IF W1$="YES’ THEN PRINT "THE FILE CONTAINS THE FOLLOWING NAMES:" Pp g 4 . y s
00250 PRINT modification. However, procedure
00260 GET #1 subroutine 2 calls several revision
00270 LET 13=13+1 subroutines (lines 4170 thru 4850)
00280 IF Wl$="Y’ THEN PRINT DS,B which should be included with it, if
00290
IF W1$="YES° THEN PRINT DS,B
Listing 4 continued on next page
30 — October 1979 © BYTE Publications Inc
it is made into a separate program.
MetaFloppy’ goes
The Micropolis MetaFloppy™ gives you more than four times the capacity of
anyone else's 54-inch floppy. Because it uses 77 tracks instead of the usual 35.
____ The field-proven MetaFloppy, with thousands of units delivered, comes
in a complete family of models, And, like our MacroFloppy™ family oF disk e
drives, MetaFloppy is designed for the S-100/8080/Z-80 bus.
For maximum capacity, choose our new MetaFloppy:1054 system. Which
actually provides you with more than a million bytes of reliable on-line stor
age. For less money than you'd believe possible. . .
The MetaFloppy:10S4 comes complete with four drives in dual config-
uration. A controller. Power supply. Chassis. Enclosure. All cabling. A new BASIC
re package. And a DOS with assembler and editor: There's even a built-
in Autoload ROM to eliminate tiresome button pushing.
If that's more storage than you need right now, try our
MetaFloppy:1053, with 630,000 bytes on-line. Or our Meta-
Floppy 4043, with 375,000 bytes on-line. Either way, you can
to over a million bytes on-line in easy stages, when you
need to. Or want to.
. In other words. if your application keeps growing, we've got
you covered. With MetaFl opp.
The system that goes beyond the floppy. ; ;
For a descriptive brochure, in the U.S. call or write Micropolis
Corporation, 7959 Deering Avenue, Canoga Park, California 91304,
Phone (213) 703-1121.
Or better yet, see your local dealer.
MICROPOLIS"
More bytes in store for you.
Another use for the information in Listing 4 continued:
the file is for studying naming tradi-
tions. Do certain names appear over 00300 !
+ a 00310 IF B>I2 THEN LET 12=B
and over in the family? Are surnames 99399 tf R>12 THEN LET 12=R
commonly used for given or middle 99339 tf T>12 THEN LET 12#T
names? Perhaps the file contains ideas 00340 co To 260
for naming your own children (pets, 00350 RESUME 390
etc). Studying names can help in the 00360
understanding of implicit family 00370 ! MENU'OF PROCEDURES
values and the transfer of power and 0d 380
ige in the famil 00390 PRINT\PRINT\PRINT
Prestige in the family. _ 00400 PRINT “PLEASE ENTER THE NUMRER OF THE PROCEDURE’
You may wish to add a subroutine 00410 PRINT “YOU WANT:”
for collecting biographical anecdotes 00420 PRINT
about ancestors. This is a real pro- 00430 PRINT TAB(10);°(1) ENTER INFORMATION”
gramming challenge, given the 00440 PRINT TAB(10);°(2) READ OR REVISE INFORMATION
rime ‘ . dae 00450 PRINT TAR(10);°(3) LIST PEDIGREE”
limited string handling capabilities of 99469 print TAR(10)3“(4) END THE PROGRAM’
most versions of BASIC. 00470 INPUT A
00480 IF A=1 THEN GOSUB 570 ENTER INFORMATION
Conclusion 00490 IF A=2 THEN GOSUB 2000 EAD THE INFORMATION
Genealogy matches you and your 00500 IF A=3 THEN GOSUB 3090 —!LIST PEDIGREE
computer against exciting and worth- 00510 IF A=4 THEN GO T0 4900 | END PROGRAM
while puzzles that challenge the best ooaag cael HINEOPHERROR-TKE ACen
abilities of both man and machine. Its 99549 t PROCEDURE SUBROUTINE #1
rewards include a closer relationship 00550 t BIRTH CERTIFICATE INFORMATION
with your family, increased know- 00560
ledge of history gleaned froma search 00570 PRINT\PRINT
for facts that may have affected 00580 PRINT “TASK: ADD GENEALOGICAL INFORMATION TO THE FILE”
ancestral migration and marriage pat- 00590 OPEN “GEN’ FOR INPUT AS FILE #1, SEQUENTIAL VARIABLE, ACCESS
APPEND, MAP GENDATA, INVALIN 130
terns, and a self-knowledge derived 99600 pRINT\PRINT
from examination of people like 00610 PRINT "WHAT IS THE PERSON’S NAME?"
yourself, Listing 4 continued on page 32
October 1979 © BYTE Publications Inc 31
Up Your
Output.
TEMPO
MULTI-TASKING!
The TEMPOS Operating System is quickly becoming the standard in Multi-
User, Multi-Tasking operating systems for 8080 and 280 microcomputers.
Multi-Tasking means that, even with only one user at one terminal, more
than one job can be running on the system simultaneously! If you have ever
had to go get a cup of coffee while you wait for your computer to print list-
ings, you know the advantages of a system that will handle one job while
you are working on another. TEMPOS is a true time sharing system, and
the maximum number of jobs is limited only by your memory.
MULTI-USER!
Want to shareyourcomputerwithanother user? With TEMPOSallit takes
is another terminal .. .up to seven_ interactive terminals are allowed! And
with Re-Entrant programs, each user does not need a complete copy in
memory. We include three Re-Entrant programs (the OPUS/THREE High-
Level Language, the TEXTED Text Editor, and FILES, a disc file
directory/manipulator) or write your own! In addition, we include an
assembler, a linking loader, over a half-dozen other utility programs and
cover 60 system subroutines, callable by the programmer!
PROVEN!
With TEMPOS, you get a package that has been tested in our facilities for
over two years, and in the field at over 50 different installations. We have
used this system ourselves for everything from writing high-level languages
todeveloping applications to text editing to games. TEMPOS is undoubted-
ly the most flexibie software tool on the market. .. and you can have it for
much less than you think!
COMPATIBLE!
TEMPOS is available for many different systems; pre-written drivers may
include yours. Or, using our interactive System Generation Routine, you
can add your own. Call or write now for our free catalog and the name of a
dealer near you. The TEMPOS Operating System is available for $787.00,
the manual set (price may be credited toward the purchase of the TEMPOS
package) for $21.50 (prices include shipping within the US.).
ADMINISTRATIVE
OOOQINC.
00
1642 S. Parker Road, Suite 300, Denver, Colorado 80231
(303) 755-9694
32 October 1979 © BYTE Publications Inc Circle 8 on inquiry card.
Listing 4 continued:
00620
00630
00640
00650
00660
00670
00680
00690
00700
00710
00720
00730
00740
00750
00760
00770
00780
00790
00800
00810
00820
00830
00840
00850
00860
00870
00880
00890
00900
00910
00920
00930
00940
00950
00960
0970
00980
00990
01000
01010
01020
01030
01040
01050
01060
01070
01080
01090
01100
01110
01120
01130
01140
01150
01160
01170
01180
01190
01200
01210
01220
01230
01240
01250
01260
01270
01280
01290
01300
01310
01320
PRINT "(USE MAIDEN NAME WHERE APPROPRIATE)"
INPUT DS
PRINT\PRINT
PRINT "TO PREVENT ";D$
PRINT "FROM BEING CONFUSED WITH SOMEONE ELSE"
PRINT "WHO MAY HAVE A SIMILAR NAME, HE/SHE"
PRINT "SHOULD HAVE A UNIQUE NUMBER IN THIS FILE."
PRINT
PRINT "HAS A NUMBER ALREADY BEEN ASSIGNED?"
INPUT VS
IF VS="¥’ THEN 820
IF V$="YES’ THEN 820
IF V$<>‘N’ THEN IF V$<>’NO’ THEN GO TO 690
LET 12=12+1
LET B=I2
PRINT
PRINT "HE/SHE HAS BEEN ASSIGNED THE NUMBER:"
PRINT
PRINT TAB(10);B
GO TO 850
PRINT
PRINT "PLEASE ENTER THE NUMRER:"
INPUT B
PRINT\PRINT
PRINT "I WILL ASK YOU FOR SOME DATES."
PRINT "PLEASE ENTER DATES IN THE FOLLOWING"
PRINT "FORMAT: DAY MONTH = YEAR"
PRINT "EXAMPLE: 23 APRIL 1949"
PRINT "IF YOU DON’T KNOW A DATE, ENTER ‘UNKNOWN’."
PRINT\PRINT
PRINT “WHEN WAS ‘;D$;° BORN (DA MO YR)?”
INPUT E$
PRINT
PRINT “WHERE, WAS HE/SHE BORN?"
INPUT HS
PRINT\PRINT
PRINT "WHAT WAS "3D$;'S FATHER’S NAME?"
PRINT "(IF YOU DON’T KNOW, ENTER ‘UNKNOWN’)"
INPUT Q$
IF Q$="UNKNOWN’ THEN GO TO 1200
PRINT\PRINT
PRINT "DOES ";Q$;" ALREADY HAVE A NUMBER?"
INPUT V$
IF V$=’Y’ THEN 1160
IF V$="YES’ THEN 1160
IF V$<>°N’ THEN IF V$<>‘NO’ THEN GO TO 1020
PRINT
LET 12=12+1
LET ReI2
PRINT "HE HAS BEEN ASSIGNED THE NUMBER:"
PRINT
PRINT TAB(10);R
PRINT\ PRINT
GO TO 1220
PRINT
PRINT "PLEASE ENTER HIS NUMBER:"
INPUT R
GO TO 1220
LET R=O
PRINT\PRINT
PRINT "WHAT WAS "3D$;""S MOTHER’S NAME?"
PRINT "(USE MAIDEN NAME IF POSSIBLE. IF YOU"
PRINT "DON’T KNOW HER NAME, ENTER “UNKNOWN’*)"’
INPUT S$
IF S$=’UNKNOWN’ THEN GO TO 1430
PRINT\PRINT
PRINT "DOES SHE ALREADY HAVE A NUMBER?"
INPUT VS
IF VS=’¥’ THEN GO TO 1400
IF V$="YES’ THEN GO TO 1400
IF V$<>’N’ THEN IF V$q>‘NO’ THEN GO TO 1270
Listing 4 continued on page 42
1.2 million instructions per
second. Average.
Memory to accumulator ADD
time — 600NS.
JUMP extended — 900NS.
o SMIPS: 0 MIPS ‘1.5 MIPS
The C4P and the C8P offer
more display than other
personal computers — 2048
characters — 32 rows of 64
columns with upper and lower
case. Long display width
makes user instruction easier
to program and to read. The
effective graphics resolution of
256 x 512 points allows these
computers to match the display
limit of even the best color
television sets.
Speed separates the computers
from the toys. The faster the
processor executes instructions
the more elaborate and greater
the I/O can be. The C4P and
C8P have execution speed that
is twice as fastas Apple II, or
Commodore PET and over
'TRS-80 B/W
THREE times as fast as TRS-80. |/apprencolor
They are many times faster
than the recently introduced LE Type Computers
flock of video game type 7 1
computers. is Ceinacnets =
GT OPTION As if that
weren't fast enough, the C4P
and C8P’s speed is nearly
doubled when equipped with
the Ohio Scientific GT option.
By utilizing a 6502C
microprocessor in conjunction |
with ultra-fast static memories,
a C4P or C8P equipped with
the GT option, will yield the
following performance:
ae tT at
* Apple I, Commodore PET, TRS-80, and Atari 800 ere registered trade names of Apple
Computer Inc., Commodore Business Machines Lid., Radio Shack, Atari. respectively.
$+
16 COLORS
The C4P and C8P offer a bril-
liant array of 16 colors includ-
ing black available in both
alphabetics and graphics.
CONSTRUCTION
The C4P incorporates a fully
RF shielded aluminum case
with 2-step baked on enamel
finish. It is trimmed with solid
oiled walnut and die-cast
chromed dress panels. Com-
pare its construction to the
plastic cases that are standard
on other personal computers.
The quality doesn't stop at the
surface. The C4P and C8P
are modular BUS orientated
computers with 4 and 8 slots
respectively. The internal
electronics are built to rigorous
industrial standards.
Modularity means expand-
ability and obsolescence pro-
tection. In fact, the original
1977 vintage C2-4P can be
upgraded to a C4P by chang-
ing PC cards at substantially
less cost than purchasing a
new computer.
Circle 300 on inquiry card.
The C4P MF is shown with optional
accessories (clockwise). Home
Color TV set (requires RF mod-
ulator), 2 joy sticks, AG-Remote
console and 2 modules, wireless
smoke detector and window
detector, modem, printer and
wireless ramote security console
(on top of TV.)
JUST LOOK ATALLTHE! O
OF THE G4P MF
— BUILTIN
INTERFACES
(Coals)
I/O capabilities. The most
important feature to look for /
when you purchase your next
computer. Compare these
standard features of the C4P
and C8P disk systems to any
other computer system.
Regardless of price, you'll find
none that even come close.
CONTROL
Model
1-Real time clock and POWER
count down timer ON
ON/OFF Switch
Only on Ohio Scientific
C4P MF or C8P DF
can offer you all this 1/0.
INTERFACES
16 parallel I/O lines
HOME SECURITY
INTERFACES
1-home security interface with
fire and intrusion detection
p= iL
Aurora, Ohio 44202
Serial
FUSE
(2A)
110 VAC
60 Hz
Fuse
RS — 232 PORTS
1-300 baud modem port
1-300/1200 baud printer port
Directly connect to an optional
modem and
AVAILABLE ON THE BACK
AND READY TO RUN.
ACCESSORY BUS
One accessory BUS connector
for an external 48 line I/O
board, PROM blaster, analog
data module or education
board.
SOUND
1-programmable tone
generator 200 — 20KHz
1-8 bit companding digital to
analog converter (DAC) for
music and voice output
Cassette IN
(Cassette Versions Only)
Color Adj. Video Display
SE | —
Cassette OUT
(Cassette Versions Only)
HUMAN INPUT
EXPANSION
| 2-8 axis joystick interfaces
2-10 keypad a=
HOME INTERFACES
1—AC-12 AC remote control
interface
SOFTWARE
Ohio Scientific offers a full
comprehensive library of
both systems and applications
software for the C4P and the
C8P. And, because our main
language is Microsoft BASIC
like most other personal
computers, much of your old
software can be used on the
CAP and C8P with little or no
modification except for the
special I/O functions and the
much faster speed of yournew
computer. This would include
software from the TRS-80 Level
IL, Apple floating point BASIC,
Commodore BASIC and many
others,
SYSTEMS
INTEGRATION
There is a lot of software avail-
able fora lot of computers.
FOREGROUND/
BACKGROUND
OPERATION
This means that your computer
can be engaging in home
monitoring activities at the
same time it is running other
programs.
As you can see, the C4P and
C8P are truly exceptional
premium computers with just
their standard features alone,
Above and beyond that they
are easily expandable toadd
exciting advanced features
like word processing, addi-
tional memory, voice I/O, and
our new universal telephone
interface (UTI).
C4P VS. C8P
The C4P is a 4-slot portable
computer with one open slot
for expansion. The CAP is an
8-slot mainframe class
computer with five open slots.
Itfeatures over 3times the
expansion capability of the
Unfortunately for the user in
almostevery casethe computer
isavailable from one supplier,
software is available from a
dozen independent suppliers
and accessory devices are
available from yet other
suppliers. Ohio Scientific has
a different approach. We offer
a comprehensive library of
systems and applications soft-
ware for the 4P and 8P. In fact,
we offer more factory sup-
ported software than any other
personal computer company.
For example, say you havea
brand X computer and you buy
a real time clock from com-
pany ¥ which supplies software
CAP for advanced home,
experimental and small
business applications. The
C8P's dual 8" floppies store
about 8 times the information
ofasingle mini-floppy and
access it many times faster.
ADVANCED
FEATURES FOR
C8P DF EXPANSION
Voice I/O
The CBP DF can be optionally
equipped with a voice I/O
system that includes a Votrax
module capable of generating
English speech phonetically.
It also has provisions for a user
populated 5-channel feature
extractor for voice input
experimentation.
Universal Telephone
Interface (UTI)
Optionally equipped with a
Universal Telephone Interface
system, the C8P DF has the
ability to dial any telephone
number, utilizing rotary dial or
touch tone telephone lines. It
can respond to touch tone or
*TRS-A0 Level Il, Appleiloatingpoint BASIC and Commodore BASIC are reqistered
trade names of, Rado Shack, Apple Computer Inc.. Commodore Business Machines Lid.,
respectively.
to use the clock. Then you
buy an AC controlier from
company Z who also provides
software. The system works
fine as long as you want to
monitor time or control AC
devices but you are out of luck
when you want to use the clock
in conjunction with controlling
AC devices. With Ohio
Scientific's systems you can be
monitoring home security,
time, controlling AC devices
and be playing an exciting
video game, all at the same
time because the systems
software, the applications soft-
ware, and the accessories form
an integrated package which
works together without end
user modification.
modem signals and can route
voice to tape recorders.
Itcan answer by touch tone,
modem, stored message or
Votrax voice output (when
equipped with Votrax module
or used in conjunction with a
CA-14 Voice 1/0.)
ACEP DF with UTI, voice
output, AC-Remote, home
security and its clock yield the
home computer of the future
with uncannily human-like
capabilities to communicate
via phone lines and operate
and monitor typical home
functions.
FINAL FACTS
Buying a new computer is a
serious, long-term investment.
So we invite you to shop
around and compare. The
closest thing you'll ind toa
C4P or C8P will cost twice as
much and offer less than half
the performance. We know.
Because there'snothing like
these exceptional premium
computers at any price, any-
where. And probably won't be
for a very long time.
SPECIFICATION
CHART
FEATURE
Microprocessor type
GT option 6502C
Full 53-key Keyboard
BASIC in ROM
BASIC on Disk
Minimal Config. RAM
Minimal Config. Total
Memory RAM + Display +ROM
Maximum RAM
TV/Video Monitor
Cassette Recorder
Mini-Floppy Disk
Dual Mini-Floppy Disk
Dual 8” Floppy Disk
Video Display
Color Graphics (up to 16 colors),
Upper and Lower Case,
Graphics + Gaming Elements
Effective Screen Resolution
Audio Output (200 to 20KHz)
DAC for Voice and Music
Generation
Key Pad Interfaces
Joystick Interfaces
AC Remote Control Interface
Audio Cassette Interface
Real Time Clock
Home Security System
Interface
Printer Interface
Modem Interface
16 Parallel Lines + Acc’y. BUS
GT Option
Winchester Hard Disks Option
Voice I/O
Telephone Interface
; £
~ 9
SI 1S LS
O I Ie Id
| 6502 6502 6502 6502A
Yes Yes Yes Yes
Yes No Yes No
No Yes No Yes
| 8K 24K 8K 32K
19.5K 27.5K 19.5K 35.5K
* | eK 48K 32K 48K
Acc'y. Acc’y. Acc’y. Acc’y.
Acc'y. No Acc'y. No
Acc’y. Yes No No
Acc’y, Acc'y. No No
No No Acc'y. Yes
32 x 64 32 x 64 32 x 64 32x 64
Yes Yes Yes Yes
| 256x512 | 256x512 | 256x512 | 256x512
| Yes Yes Yes Yes
Yes Yes Yes Yes
Yes Yes Yes Yes
| Yes Yes Yes Yes
Yes Yes Yes Yes
Yes No Yes No
No Yes No Yes
No Yes No Yes
Yes* Yes Yes* Yes
No Yes No Yes
No Yes No Yes
| No Acc'y. No Acc'y.
No No Acc'y. Acc’y.
No No Acc'y. Acc'y.
No No Acc’y. Acc'y.
Circle 300 on inquiry card,
‘*Not wired to connector.
Computers come with keyboards and floppies where specified. Other
equipment shown is optional
SOF
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