A PUBLICATION OF THE HARVARD GROUP
IN THIS ISSUE
Return on Investment... 6
Spelling Word Game....15
The Timex Personal
Computer Made Simple .
Mastering Your Timex
Computer . 15
Winky Board II.10
POKE Down And
Program Improvements.... 3
Index of Advertisers
E-Z Key. 15
Loeser, William M.D....19
TIMEX: 16K TS2000 SCRAPPED; SOFTWARE DEALS
Timex will produce only 48K RAM versions of
the TS2000, called the TS2068, says Timex
spokesman Carl Folta. The $199 TS2068 will
experience further delays, with release now
set for the middle of September. Folta gave
no reason for the plan changes. In other
news, Timex will offer a software deal—buy
two, get two free, starting in August.
ZX84 IN THE WORKS
Sinclair Research plans in mid-1984 to intro¬
duce the ZX84, a new microcomputer using Sin¬
clair's flat 8" CRT and microdrives, reports
the Dutch periodical Elektronica (6/1/83).
Later this year, Sinclair plans to introduce
the $60 microdrive, a new type of memory that
can store more than 100K bytes of data; up to
eight drives can run on one computer. Sin¬
clair may also offer the microdrive to Spec¬
trum users. Sinclair Research denied comment
on the news, saying the info is classified.
EXCUSE ME r THAT'S SIR CLIVE
Queen Elizabeth II of England knighted Clive
Sinclair on June 11, honoring his accomplish¬
ments as inventor of the ZX/TS computer. Sir
Clive said the event inspires him to achieve
further success for Britain.
SQ and SYNTAX staffers regretfully announce
that SYNTAX QUARTERLY magazine has ceased
publication, due to financial difficulties.
We express sincere appreciation and thanks to
all who contributed to, read and supported
SQ. We hope you will extend this support to
SYNTAX, so we can continue to provide ZX/TS
users with a high-quality publication. Sub¬
scribers will shortly receive a letter offer¬
ing valuable product alternatives to SQ.
NEW PRODUCTS AND SERVICES
INVENTORY program for small busi¬
nesses or collectors. Keeps track
of assets. Tape, instructions $10.
MAGIC WORLD SOFTWARE, POB 1184,
Olympia, WA 98507.
Consulting services for software
marketers: contract negotiations,
product packaging advice, legal
assistance. Electronic Media Asso¬
ciates, 161 W. 15th St., Suite 7E,
NY, NY 10011, 212/620-3964.
Expect new TS books this fall. New
American Library and dilithium
Press contracted for a new computer
book series, including .51 Game Pro¬
gra ms for the TSl000 &. 1500 by Tim
Hartnell (due in Sept., $2.50) and
Things to Do w ith Your TS200 0 by
Jerry Willis and Merl Miller (due
in Nov., no price set).
Floating point extension for XFORTH
available in Sept., $15 +$1 P&H, 4%
AR res. tax. XFORTH XCHANGE, forum
for XFORTH, FORTH-79 users, free
with HAWG WILD product info. Send
ideas, questions. XFORTH XCHANGE,
c/o HAWG WILD Software, POB 7668,
Little Rock, AR 72217.
Aircraft Performance charts climb
rate vs. airspeed to compare per¬
formance with varied altitude,
weight, power, $7.95. 16K listing,
specs for 250 aircraft from Bob
Fingerle, POB 7793, Fremont, CA
TS1000 64K RAM under $100. Glad¬
stone Elec., 1585 Kenmore Ave.,
Buffalo, NY 14217, 716/874-5510.
Programmer's Pipeline maintains
software listings for buyers and
sellers. Buyers—$150/yearly for
mailings and database access. Sel¬
lers—$20/listing. Ask for free
Checklist for Program Authors (send
large SASE, mention SYNTAX). Pro¬
grammer's Pipeline, POB 666, Glen¬
dora, CA 91740, 213/914-4317.
Free info on producing instruction
manuals for software, electronics.
Manual printing/production services
also available. Rudy Molho, Coun¬
sel Press, 30 E. 40th St., NY, NY
MATH TEACHER drills students
through jr. high level. Covers the
four basic math operations. Needs
16K RAM. $29.95, CompuTech, Dept.
TS-MT-STX, POB 7000-309, Redondo
Beach, CA 90277, 213/375-6391.
World Users Exchange collects and
sends ideas, info, to users groups.
Publishes reports, newsletter.
Free, World Users Exchange, POB
12132, Roanoke, VA 24022.
Family Health Records program keeps
medical records, 16K, 64K versions.
$12.95 includes P&H (83^ tax NY
res.). Pyramid Software, POB 813,
Pearl River, NY 10965.
LODAB merges 2 BASIC programs, oc¬
cupies 1.4K. BASIC area memory
chart displays memory used and
remaining. BDLS deletes, copies
blocks of BASIC lines, occupies
3/4K. Both in ML, self-starting,
automatically reset RAMTOP, need
16K. Use together or separately.
$18.00 ea., THE ULTIMATE BLACKWOOD,
POB 7427, Santa Cruz, CA 95061.
MIJID Software trade show for per¬
sonal computers in Cannes, France,
Oct. 3-7. U.S. rep. Harvey Seslow-
sky, 100 La Fayette Dr., Syosset,
NY 11791, 516/364-3686.
SyncWare News bimonthly newsletter
for TS electronic/math/physics ap¬
plications, with focus on technical
program listings, tutorials on com¬
puter use, tech, subjects, hardware
mods. $15/yr. SyncWare Co., POB
5177, El Monte, CA 91734.
Chemistry Tutor teaches intro
chemistry concepts. 16K, cassette
$16. H.R. Brady, 301 Pine St.,
Neptune Beach, FL 32233.
Computer graphics conference "Ap¬
plications on the Leading Edge,"
Oct. 24-25. Presentations for en¬
gineers, architects, artists, doc¬
tors. For info contact Conference
Secretary, 2nd Annual Pacific
Northwest Computer Graphics Confer¬
ence, 111 Susan Campbell Hall, U.
of Oregon, Eugene, OR 97403-1204,
TimeWare product line—8 books, 7
game tapes, 6-vol. cassette series
to teach kids math. Software needs
16K, runs on TS1000, 1500. Reston
Publishing Co., 11480 Sunset Hills
Rd., Reston, VA 22090, 800/336-
0338, or TS stores and bookstores.
FYLIT tm provides user-generated
custom database applications—file
configuration, multi-field sorting.
Requires 64K, CAI P40 printer, CAI
Exatron stringy floppy. 50-ft.
wafer $30. Free catalog. BIOCAL
SOFTWARE, 167 Wilson St., Petaluma,
CA 94952, 800/237-8400 x70.
Fantasy Plaza software "shoppes"
include TS software, hardware. Or¬
der by modem (1-213-244-1100),
phone plaza operator #12, (800/824-
7888, 800/824-7919 AK, HI) or shop
by mail. Fantasy Plaza, POB 6055,
Burbank, CA 91510.
GRADEBOOK records grades, weights
scores, does statistical analysis.
Tape $12.95. EPHEMERIS V planet
finder reports location of any
celestial body, computes lunar
phases, includes graphics. Tape
$14.95. Both 16K. S&H $1.25/
order, $10/Express Mail. Robotec,
59 C St., Ampoint Industrial Pk.,
Perrysburg, OH 43551, 419/666-2410.
M icrocomputer Programs in Print
software reference guide, includes
Timex and independent TS software.
Includes 280 software categories.
Money back guarantee. Ppbk., 208
pp. $22.25 includes tax, S&H.
Postroad Press, Inc., POB 1212,
Roanoke, VA 24006, 703/342-9797.
GOLF PARTNER (Jul.83) does not com¬
pute golf handicaps (lines 735-745)
according to US Golf Association
guidelines. The USGA formula aver¬
ages the ten lowest differential
scores (gross golf scores minus
course ratings) of your last 20
rounds, muliplies the average by
0.96, and rounds off to the nearest
whole number. Rev. Glass' formula
averages the ten most recent gross
scores, subtracts 72, multiplies
the difference by 0.85, and rounds
down to the nearest whole number.
John Carson, Jr., Takoma Park, MD
Substitute GOTO 80 for GOTO 75 in
line 60 of WEATHER FORECAST (Jul.
83) for proper programming tech¬
nique. Although the program lacks
a line 75, the listing as printed
works. ZX/TS computers jump to the
next higher line (80) when they
As noted in Jun.83, my BASIC Syn¬
tactic Sum (Feb.83) can give a
different result than the MC ver¬
sion when checking long programs.
This improvement gives the same
result as the MC version, whatever
the program length.
Just enter these lines at the
end of your program, then GOTO 9600
to calculate the Syntactic Sum.
If you want to use this pro¬
gram with different line numbers,
first enter it by itself , using
your line numbers and replacing the
10310 at the end of line 9607 with
a single 0. RUN it and jot down
the value of S. Then enter the
following program, using the S
value you wrote down for the value
of D in line 10:
Make sure your machine is in FAST.
RUN, then go dry the dishes or walk
the dog. When you return, the com¬
puter should show a 0 in the right
column. Substitute the correspond¬
ing number in the left column for
the 0 in the next-to-last line of
Syntactic Sum. DELETE the second
program and RUN Syntactic Sum. Now
S should equal 0.
If the second program never
gives you a 0, press BREAK. (If no
numbers appear on the screen, enter
CONT and press BREAK again later.)
Pick the smallest absolute value in
the right column. Divide it by 3
and reverse the sign (multiply by
-1). Change the three K variables
in lines 9602 and 9606 to the let¬
ter that number ahead of or behind
K in the alphabet. For example, if
the number is +2, change K to M (K
+2 letters = M). Revise the next
to last line as explained in the
previous paragraph (substitute the
Lloyd Painter, Quakertown, PA
To execute 8K MC Video Invert (Jun.
83) more easily, enter this loader
program (line 1 contains 28 charac¬
ters after REM):
RUN, then input the decimal numbers
from Jun.83, p.21. After the last
number, delete lines 10-70. To use
the routine, enter RAND USR 16514.
Stephen Brothers, Aurora, CO
ZX/TS USERS 1 GROUPS
To list your group or find one in
your area, call or write SYNTAX.
Portsmouth, OH: R. Arthur Gindin,
1823 Kinneys Ln., Portsmouth, OH
Cincinnati, OH: Timex/Sinclair
Users Group of Cincinnati, Rick
Johnson, 11 Funston Ln., Cincin¬
nati, OH 45218, 513/825-1449.
Pittsburgh, PA: Pittsburgh Area
Computer Club, Special Interest
Group—Timex/Sinclair. New address
and leader: Ed Mihalo, 152 Deer¬
field Dr., Pittsburgh, PA 15235,
Oologah, OK: Billy Casebeer, T/S
Users Group, POB 372, Oologah, OK
74053. Interested in hearing from
ZX/TS owners in any area.
Sheridan, WY: John E. McWilliams,
Sheridan Microcomputer Users Group,
Rt. 2, Box 511, Sheridan, WY 82801,
307/674-4954. Includes ZX/TS users.
Newark, DE: Julio C. Bezerra, 371
Moir St., Newark, DE 19702, 302/
S. Bound Brook, NJ: Amateur Compu¬
ter Group of New Jersey, POB 319,
South Bound Brook, NJ 08880.
FULL SIZE KEYBOARD
A ■ « nAI A Wk 1
If you’re tired of not knowing whether your data got entered or tired of pok¬
ing data in with one or two fingers, then it’s time to upgrade your ZX-81 to
a full size, professional keyboard. The SUN KD-81 KEYBOARD offers all
the ease and comfort of inputting your programs and text on a fast and ef¬
ficient professional-sized keyboard!
• No Soldering
• No Modifications
• Full size keyboard with 41 keys
• Two color silk-screened key tops
for easy reading
• Key tops have commands and
graphics spelled out the same as
• Extra shift key for real keyboard-
• Full size space bar
• Allows touch typing
• Rear cutout allows any RAM or
expansion module to be plugged
• Keyboard comes with own cables
• Keyboard case holds both
keyboard and computer with room
• High impact plastic case with
vaporized metal shielding
• Easy assembly — no soldering,
• Measures 10%" x 7 V/' x 2 Vs"
GET A BETTER PICTURE WITH SAMWOO MONITORS
SAMWOO provides a much better picture for your Sinclair
Computer than your TV monitor. Simple modification pro¬
cedure includes easy-to-follow instructions.
• Composite Video
• Switchable Input
Impedance 75 or
• 750 Line Resolution
at Center and 500
Lines at Corners
• Dimensions are
9" 18Mhz BANDWIDTH 12" 12Mhz BANDWIDTH 12.13" x 11.34" x
Green.$121.00 Green.$130.00 11.65" for the 12"
Orange.125.00 Orange. 134 00 model and 8.66" x
8 54" x 9 05" for thp
Add $7.50 Shipping and Handling for this item. ° iur mt;
> Built-in output connector for piggyback
> Lip for mounting on ZX-81 & KD-81
> High-impact plastic case with vaporized met
>6.6" wide, 3.2" high, 1.08" deep
16K $49.95 MX-16KP
64K $119.00 mx-64kp
sumowcs co„ INC.
12621 Crenshaw Blvd., Hawthorne, CA 90250
STORE HOURS: MON.-FRI. 9:00 am to 6:30 pm
SATURDAY 10:00 am to 5:00 pm
CALIFORNIA OUTSIDE CALIFORNIA TOLL FREE
213 - 644-1149 1 - 800 - 421-5775
(for Tech Info and Calif, orders) (Order Desk Only)
Mail Order — Minimum Order $10. Send Money Order or Check to P.O. BOX 1957 —
HAWTHORNE, CA 90250. VISA or Mastercard (please include expiration date).
Add $4.00 postage and handling to order. CA residents add 6% sales tax.
Although Timex's new TS2068
will appear shortly, they have kept
most specs under close wraps.
SYNTAX gathered this information
about the new machine.
Onboard you'll find a Z80A
processor with a new design for
multimegabyte bank-switchable RAM.
A new Sinclair flat-pak logic chip
with 68 pins is bonded directly to
the board. General Instruments'
AY38912 sound chip provides three
voices and a single envelope.
Timex has sent the ROM for
manufacture. They now await 500
prototype units, so expect release
within the next couple months.
Electronically, the keyboard
works like the TS1000, but mechani¬
cally it resembles the Spectrum.
Keys with indented tops and home-
row dots on two keys allow easier
touch-typing. Large moveable keys
give tactile feedback; an internal
speaker provides audio feedback.
Six of the buffered edge con¬
nector pins provide red, green and
blue video output plus intensity
and ground. Modulated video goes
to your TV through a coaxial con¬
nector like the TSl000's.
Timex plans to make several
unspecified languages available.
According to our report, the
cassette input has automatic level
control and works reliably at 1200
baud, adjusting for recorder speed
using a tone header.
Your TS2068 will use a full
bit-mapped graphics display of 256
xl92 pixels, with one bit of attri¬
bute per pixel (yielding 6K of
attribute memory and 6K of pixel
memory). It has a 64-column mode.
You can get 512x192 pixels by set¬
ting up two display files, and an
80-column display is possible. The
hi-res video copies character pic¬
tures onto a hi-res screen (a meth¬
od used by Apple's Lisa).
All driven by a hefty power
supply with 1A extra power and
still under $200.
RETURN ON INVESTMENT—8K/16K
What percentage return do your
investments earn? If you play the
stock market or own mutual funds,
you may not know the rate of return
from multiple investments. This
program computes compounded annual
rates of return on single invest¬
ments and monthly annuities. RE¬
TURN calculates up to 20 single and
four annuity investments, which you
can make at different times.
RETURN works by calculating a
figure based on a trial rate of
return. It then compares this
number with your investment's cur¬
rent value. If the difference is
greater than 0.1%, the computer
picks another trial rate and re¬
peats the computation. This itera¬
tive process (repeated adjusted
trials until arriving at the cor¬
rect response) is a perfect time¬
saving application for computers.
Type in the program and RUN.
For your first entry, don't re¬
evaluate loaded data (previous en¬
tries) when asked. Hit N for No
and the program asks you for the
month, date, year and amount of
your first single investment. Hit
0 then ENTER to exit this data in¬
put section when desired. After
you exit the single investment sec¬
tion, the program asks for monthly
annuities. After you ENTER infor¬
mation on these, hit 0 then ENTER.
The screen then blanks as the com¬
puter calculates. Be patient, and
you will see your rate of return
and ending balance displayed (the
margin of error). An ending bal¬
ance of $1 on a $1000 investment
means your investment may actually
fall between $999 or $1001.
Press Y when asked if you want
to SAVE the data to tape. Then,
you can recalculate your return
rate later with a new monetary
value of your investments. The
program self-runs after you SAVE
your data. You cannot enter more
info if you SAVE and recalculate
Hit N if you don't want to
SAVE your data, generating report
code 9 (STOP). Press RUN to start
another round of investments.
If you want to enter more than
20 single investments, change the
number 20 in lines 1240 and 1320 to
the number desired. To enter more
than four annuities, change the
first numeral four in line 1250 to
the number of annuities desired,
and change the numeral four in line
1530 to the same quantity.
Program limitations: calcula¬
tions stop if the rate of return is
less than 1%. The program computes
only gains, not losses. Computa¬
tion time can take awhile, partly
because the program accurately cal¬
culates the number of days between
two dates (lines 30-150, 300-420,
510-630) for more exact results.
To achieve a greater accuracy
than 0.1%, first convert the de¬
sired accuracy to a fraction. For
example, represent 0.05% accuracy
with the fraction 5/10,000. Then
multiply this fraction by the term
in line 690. The line reads as
follows, with changes highlighted:
690 IF ABS (C(4)-Y) <5C(4)/10 r 000.
Russell Crum, Canton, MI
601 West Cliveden Street
Philadelphia, PA 19119
WHY PAY $49 ? ?
T/S 1000 — ZX81
Assembler handles all source statements & lists
to TV or printer. Editor features move/delete block,
find string/tag & scroll functions. Loader (650 baud)
saves source files & your machine programs indepen¬
dent of BASIC. And your programs can access
load/save routines. . .
(cheque or money order)
SET RAMTOP AUTOMATICALLY
This progam automatically sets
your machine up for machine code
routines in high memory by moving
RAMTOP. I don't like to figure a
new RAMTOP by hand, then POKE the
right number into the right loca¬
tion. This program does it for
you, displaying the new RAMTOP and
the two numbers to POKE. To POKE
RAMTOP yourself, write down the
numbers in the box and POKE them,
following the example on pp.124-5
(Chap. 25, Using Machine Code) of
the Timex manual. Or the computer
will POKE them for you. Enter and
run AUTO RAMTOP before entering
your other programs.
Another handy use: suppose
your program uses 4K RAM. To speed
it up, enter the number of bytes
not used (subtract the number used
from 32768 if you have 16K) or en¬
ter 1024 times the number of K not
used. For example, your program is
4K bytes long; you have 16K RAM.
Enter 1024*12. Then LOAD and RUN
your program—it runs faster.
SAVE the program before it
RUNS to avoid the line 995 wipeout.
BYTES How many bytes in routine
(number to subtract from RAMTOP)
NA New Address to locate RAMTOP
RE Remainder after dividing NA by
256*A (See lines 60&230)
A Whole number to multiply by 256
and add to RE to get NA
Graphics and Inverse Video
line 800 graphics E 17 graphics 7
line 810 graphics 5 graphics 8
line 820 graphic W 17 graphic 6
line 960 "DONE"
Todd Montague, Graham, WA
HDMR-12 VIDEO MONITOR/RECEIVER $99.95
THE HDMR-12 IS THE PERFECT COMPANION TO THE SINCLAIR ZX-81/TS1000, A
FLIP OF A SWITCH CHANGES IT FROM A NORMAL 12" B & W RECEIVER TO A HIGH
DEFINITION MONITOR, INPUT IMPEDANCE IS 75 OHMS WITH A SENSITIVITY OF
1.0 VOLT PEAK TO PEAK. INTERFERENCE FROM LOCAL T.V. STATIONS IS
TOTALLY ELIMINATED IN THE MONITOR MODE AND CHARACTER DEFINITION IS
ASTOUNDINGLY SHARP. ADD $8.50 SHIPPING AND HANDLING PER MONITOR. WE
CANNOT SHIP MONITORS OUTSIDE THE CONTINENTAL UNITED STATES. ARIZONA
RESIDENTS ADD 6% SALES TAX ( $6.00 ). WE CANNOT ACCEPT COD OR CHARGE
CARD ORDERS. ALLOW 4 TO 6 WEEKS FOR DELIVERY. CERTIFIED CHECK 0R^
MONEY ORDER SPEEDS DELIVERY.
RANDOM ACCESS PHOENIX.°ArSzONA 85080 j
Product: Winky Board II tape
filter and duplicator
From: G. Russell-Electronics
RD 1 Box 539
Centre Hall, PA 16828
Price: $19.95 assembled
$14.95 kit + $1 S&H
Winky Board's designer bills
it as a tape sound conditioner that
lets you save bad tapes and copy
any ZX/TS tapes, but Winky copies
better than it saves.
Proper matching of the imped¬
ance of two recoders results in the
board's duplicating success. Out¬
put for most cassette decks is 4-6
volts at 8 Ohms (speaker). Desired
input is typically in millivolts at
600-1000 Ohms (microphone). Winky
Board matches these, letting you
exactly duplicate any tape.
While the duplicating feature
works all the time, the SAVE fea¬
ture is only marginal. Two LED
indicators show when your recorder
reaches proper recording levels.
On really poor tapes, the light is
hard to discern. If neither LED
lights even a little, your tape is
too bad even for Winky to save.
Winky helped me load about 50% of
my extensive bad tape collection.
Some of the unloadable ones con¬
tained speed distortions; the
board cannot do anything for those.
Winky Board filters the tape data
to eliminate computer or RAM pack
Kit assembly seems improved
over Winky Board I; you need to
solder only 3 joints in this pas¬
sive device. Considering its sim¬
plicity, I recommend you buy the
kit. You get a simple high pass
filter (resistors and capacitors),
two indicator LEDs and an impedance
matching network of resistors. One
miniplug and three jacks provide
input, load and duplicate output
levels and an eavesdropping point.
Manufacturer Bill Russell enclosed
the jacks to correct an initial
problem in Winky Board I of a loose
jack touching exposed metal.
Despite its drawbacks, this
product can pay for itself with one
use if you save an otherwise un-
Paul Donnelly, Centerport, NY
We found Winky II helps find the
correct LOADing volume because the
LED lights at that point. You can
shorten LED#l's life by turning the
volume too high. It doesn't blow,
but it gradually burns out.
LOADing instructions were good
and easy to follow, but the other
procedures were a bit sketchy. For
example, we weren't sure in the
double-SAVE hook-up diagram where
to connect the computer.—RWK
The Direct Connection
is Here .. .
. . . foryour Timex-Sinclair computer. Memotech can now connect you to CompuServe
with our new modem package. With this introductory offer you get a 300 Baud J-Cat
Modem by Novation. . . RS232 serial interface with built-in communications software
and all connecting cables. PLUS, you get a CompuServe Demopak, password, I.D. and
log on/off procedures for a free two hour demonstration of the CompuServe Information
Memotech, the leader in add-on Timex products, introduces the modem package for
only $199.95 + $6.95 shipping/handling. (Suggested value $290.00).
Simply plug in our direct connect add-on products to the back of your Timex computer.
The Memopak 1 6K sells for $49.95 *. . . 32K Memopak is $99.95 * and our best seller
64K Memopak is $149.95 *.
The Memotech keyboard is priced at $99.95 *. The Centronics parallel interface sells
for $74.95 * including software, and the RS232 interfaces are $99.95 *. Printer
packages are also low, low priced.
Order at no risk (10 day money-back guarantee); Call 1-800-662-0949
(Colorado 1 -303-986-1 51 6). Or send your name, address, phone number and a
check/money order/Visa or MasterCard number with expiration date to:
Memotech Direct Sales Division
7550 W. Yale Avenue, Denver, Colorado 80227
* Shipping/Handling $4.95; Colorado Residents add applicable sales tax.
know of some way to modify my JRS
to open up the 8K-16K area?
During the hot summer months,
store your ZX printer aluminum
printouts in a dry place. My pro¬
gram printouts developed black
spots when kept in a humid base¬
ment, making them unreadable.
Richard Bryan, Falmouth, MA
I discovered an easy fix to an
annoying problem. One of my ZX81
keyboard's foil tracks broke be¬
tween the keyboard and its connec¬
tor; a likely consequence of some
recent modifications to my comput¬
er. Using the schematic in SQ
(Winter82 p.47) I located the bad
track, and replaced the missing
section with aluminum foil. First,
I placed some tape on the foil to
provide enough stability when trim¬
ming. I taped this foil bridge
over the defective track with plen¬
ty of overlap on the good portion
of the conductor.
My keyboard works like new,
and I saved myself the hassle of a
Ken Hartgrove, Miami, FL
Do you know of any products to
reduce or eliminate interference?
My video display wavers when cars
drive past, or when someone runs a
Myron Felckowski, Stevens Point, WI
Any number of things could fix this
problem. Try separating your com¬
ponents, buying power backup sup¬
plies (SYNTAX Jul.83 p.7), using a
different TV, or hooking up a moni¬
tor instead of a TV.—KO
Operating manuals for the CAI
Interface Module and ESF Stringy
Floppy indicate that the 8K-16K
memory locations must be available
for the system. It works fine with
my 16K Sinclair RAM module, but not
with my JRS 64K RAM pack. Do you
Jim Alderson, Santa Paula, CA
Prevent the RAM CS from selecting
the memory in these address spaces.
See the decoding description for
64K RAM packs in SQ Summer 83.—KO
Three other ZX/TS owners and I
discovered an unusual way to solve
our LOADing problems. When replac¬
ing all four tape recorder batter¬
ies failed to fix bad LOADS in my
ZX81 kit, I used two new and two
weak batteries in my GE tape re¬
corder. I have done this for a
year with no problems—whenever the
batteries need changing, I leave
the two most recent batteries in
and add two new ones.
My three friends use TS1000S
and Panasonic or Sony tape decks,
with similar results.
Paul G. Allain, Gardner, MA
If you run the recorder from an
adjustable DC supply, you'll find a
range of voltages over which it
operates well. You can then build
a fixed regulated supply whose
voltage equals the square root of
the product of the maximum and
minimum voltages at which the ma¬
Hardware tip: The pin jacks
for power, mic and earphone contain
very weak springs, sometimes caus¬
ing you to lose programs just from
touching the power cable. I unsol¬
dered the jacks and replaced them
with better ones from Radio Shack—
ordinary panel jacks. Although I
had some difficulty wrapping a wire
around them to solder to ground and
solder the tab into the circuit,
this solution works. Result—not
one power loss in a year, and I can
pick it up or shake it without fear
of lost programs.
Robert Jenkins, Chicago Heights, IL
After attempting to perform
some of the floating point examples
given in Toni Baker's book How to
Program the ZX81 in Machine Lan¬
guage , I realized that some of the
call addresses given for various
floating point routines in the ROM
are incorrect for my ZX81. Can you
Michael Stokes, Tullahoma, TN
ZX81s built before late 1981 con¬
tained ROM bugs. When correcting
the problem, Sinclair offset all
code in the new ROM by three bytes
after 0EEFh, See SYNTAX (Nov.81
p.7) for the newer 8K ROM map. We
know no errors in Toni's book.
Do you know of an interface to
connect my ZX81 to the MPI (Micro
Peripherals Inc.) Mod. 51/52 Flex¬
ible Disc Drive with 500K storage?
It's designed to run with computers
such as those from IBM, Texas In¬
struments, or Radio Shack, which
have their own power supply and I/O
cable terminating in 34-pin PCBA
Harry D. Graham, Kingston, NY
Aerco sells the products you need:
FD-FX Floppy Disk Interface (plug¬
in) for $179, and DP-2 power supply
for $79. The power supply provides
the needed voltage for each drive
of 5V at 1-1/2 Amps and 12V at 2
Amps. Aerco, POB 18093, Austin, TX
I have two 16K RAM modules
(one is a TS1016) that can't piggy¬
back to form 32K. How can I com¬
bine the two to get more memory?
David Pinto, Jensen Beach, FL
You must perform some hardware mods
to merge your RAMs. While we can't
detail a complete solution, we can
tell you that a RAM pack knows its
address by the way address lines
and RAM CS are connected. If you
arrange to divert RAM CS from one
RAM pack to the other, you cause
the first to be active between 16K
and 32K and the second to function
from 32K to 48K. See SYNTAX (May82
p.5) for circuit hints.—KO
Can you POKE new lines into a
program without BREAKing and LIST-
ing the new line number? I can
find the address after any program
line number by PEEKing 16425, but
attempts to POKE into addresses af¬
ter those holding the last charac¬
ter in the line causes a crash or
POKES characters onto a blank
screen. Any ideas?
Tim Lichtenwald, San Francisco, CA
Ideas yes, methods no. We made a
quick pass at POKEing to the edit
file, but that didn't work. You
could create a bank of REM state¬
ments with sufficient room to hold
new names, then automatically POKE
them to active statements. You'll
find the basic method for changing
commands in SYNTAX (Feb.81 p.12),
but now you have a more complex
address-finding scheme to develop.
We know the ROM contains a routine
to insert BASIC lines, but we don't
know how to use it. If any reader
can help us, we'd be grateful.—KO
How can I convert the English
ZX Spectrum to US television stan¬
dards? Neither Timex, Sinclair,
or Ferranti carry the part I need
(Ferranti ULA #114, or equivalent).
Can you help?
Rick Barnett, Woodbridge, VA
We know of no additional sources,
but you can run your Spectrum in
black and white on many US TVs.
Also, you can buy a PAL-standard TV
or monitor that can accept various
color standards like the $600 JVC
TM-14PSN. For the monitor, you
must also use direct video just as
you would for a ZX/TS.—KO
Program: Copy Katt
Purpose: Making backup tapes
ROM/RAM requ'd: 8K/16K
From: Katt's Computers
Chicago, IL 60411
Copy Katt lives up to its ad¬
vertised claim of being able to
copy any ZX/TS software, including
machine code unlistable programs.
You must enter the 130-byte
machine code program (sold as a
listing) into a REM statement. Use
the short loader program provided
and you can use Copy Katt in about
the time it takes to enter 300
keystrokes. The disassembler list¬
ing appears to load the various
registers with high memory pointers
(over 32K) and then boots up into
the high memory areas.
Copy Katt sets itself up when
RUNning and begins the ROM tape
loading subroutine. When the tape
you want to copy LOADS, COPY KATT
automatically BREAKS and LISTS it,
letting you SAVE it the usual way.
Fast delivery rates an A: I
received my two-page program list¬
ing and instructions in less than a
week after placing my order.
Three suggestions for improve¬
ment: include the assembly lan¬
guage listing as part of the Copy
Katt package, mention in Copy Katt
ads that the routine only works for
16K programs, and include instruc¬
tions on adaptation to 2K machines.
I highly recommend Copy Katt
and give it a 10 on my 1 to 10
scale of cost-for-value.
Paul Donnelly, Centerport, NY
See the Winky Board hardware review
and the article "User Friendly
Legal Advice" for further discus¬
sion about copying software and
related legal concerns.—LFV
USER FRIENDLY LEGAL ADVICE
To get the best protection
against program-idea theft, you
must construct a patchwork shield
out of laws governing copyright,
trade secrecy and licensing or
sales. Courts usually deny patents
to computer programs because they
do not fit the legal requirements
of being "novel" or "nonobvious."
By comparison, you can copy¬
right your program easily, cheaply,
and effectively. Simply put the
copyright symbol or the word "copy¬
right," the year and your name on
the cassette label and in the pro¬
gram's first line. (See ARCHER in
this issue.) You must independent¬
ly copyright any documentation you
write as well. You establish a
valid copyright the moment you
place the copyright notice on any
work. But to enforce your rights
if you wish to sue for infringement
on your copyright, you must file
your copyright with the government.
Write to the Public Information
Office, United States Copyright
Office, Library of Congress, Wash¬
ington, DC 20559, and request Class
TX application forms. Send in the
completed form with a $10 fee and a
Copyright laws protect your
program as a whole, but not neces¬
sarily ideas embodied in your pro¬
gram, such as subroutines. Protect
these as trade secrets by including
a trade secrecy clause restricting
what a buyer can do with your pro¬
gram. A typical trade secrecy
clause might prohibit the user from
disclosing the program to any third
party, by sale or by giving copies
away. You can take legal action if
the program's user violates any of
these requirements. Imposing trade
secrets if you directly market to
the public might not be wise as it
could cut into your product sales.
Jonathan Wallace, Esq., 51 E.
42nd St., Suite 1601, NY, NY 10017
Part II coming in Sept. SYNTAX—LFV
SPELLING WORD GAME—8K/2K
As a lazy parent, I devised
this spelling game to tutor my
daughter in the words she must
learn each week for school.
Type in the program, and RUN
then ENTER. You'll see an "L"
prompt; enter five words scrambled
and then five correctly spelled
words in the same order. Press
ENTER after each entry. (No indi¬
cator tells when to go from the
scrambled to correct spellings.)
The screen instruction then tells
you to unscramble the word below.
When you're through with the five
words, decide whether you want to
play again. A yes answer lets you
play using the same words again.
To begin another round with new
words, press RUN.
SPELLING WORD GAME makes spel¬
ling practice more enjoyable for my
daughter; the game provides visual
encouragement and rewards her with
more words to try when she's right.
Adults can enjoy this by play¬
ing cryptoquote or other scrambled
Frederic Bogar, Key West, FL
NOT JUST A KEYBOARD REPLACEMENT
BUT AN ENHANCEMENT THAT GIVES
KEYBOARD FEATURES FOUND ONLY
ON MORE EXPENSIVE COMPUTERS.
FOR FASTER & EASIER DATA ENTRY
WITH YOUR E-Z KEYBOARD . . .
Here at last, is a large 60 key “TACTILE
FEEL" keyboard that plugs into the same
connectors as the existing keyboard on
your ZX81, TIMEX/SINCLAIR 1000 or 1500
HERE THE CLICK... FEEL THE SNAP!
for every key pressed (tactile feedback)
IT’S THE ONLY KEYBOARD WITH ALL OF
• 60 moving keys: solid (not rubber)
• Legends in three colors on the base (color coded by key functio
• Molded legends on keytops (no stickers)
• 8 automatic shift keys (no shifting required) for edit, delete,
single & double quotes, colon, semi-colon, function and stop
• 2 shift keys
• Numeric keypad
• No wiring required (Just plug in)
Cables and instructions are included
above) is available for yc
EC-11 (11" X 9“ X 3.5")
EC-14 (14" X 9" X 3.5”)
A joystick kit that requiri
like the arrow keys and C
Plugs into E-Z Key 60 keyboarc
Suite 75, Dept. CE
| 711 Southern Artery
I Quincy, Massachusetts 02169
The Timex Personal
Computer Made Simple
Joe Campbell, Jonathan
D. Siminoff, Jean Yates
Signet/The New American
P.O. Box 999
Bergenfield, NJ 07621
$3.50 (ppbk., 152 pps.)
Mastering Your Timex
Tim Hartnell and
Bantam Books, Inc.
414 E. Golf Rd.
Des Plains, IL 60016
$3.95 (ppbk., 208 pps.)
Each of these books costs less
than other ZX/TS books because of
their small size and cheap paper.
I recommend both books for their
price alone, though Hartnell and
TIMEX MAKES MEDICAL WAVES
Jones wrote a much clearer book
than Campbell et al.
As its name might imply. Made
Simple seems to talk down to the
reader. The text tries to keep
things light and breezy, and in¬
cludes many cartoons. Despite
this, I found the book confusing,
with too much text and too few
After two short how-to-plug-
it-in chapters, the book moves
quickly into five chapters that
explain some programming concepts,
then progresses into four chapters
of programs. The book's six appen¬
dices include computer anatomy, re¬
sources, a glossary, report codes,
Program listings in regular
type pose problems. For example,
no slash in numeral 0 confuses it
with letter 0 in some listings.
By contrast, Hartnell and Jones
give you over 65 programs for less
than $4 with a lot of valuable
information in Mastering Your Ti¬
mex . Their underlying attitude
seems different from Campbell's—
they assume you want to learn and
work hard to help you. As founder/
coordinator of the National ZX
Users' Club of England, Hartnell
brings to this book his experiences
working with Sinclair users.
This book contains short chap¬
ters that cover beginning program¬
ming concepts, plus such topics as
PEEK and POKE, MOVING GRAPHICS, and
converting other BASICS. Hartnell
and Jones use high-quality illus¬
trative programs. Appendices cover
utilities such as hexadecimal con¬
version, bytes remaining, and how
to simulate 2K memory with more
memory attached. Program listings
read exactly like your TV screen.
Mastering Your Timex Sinclair
Personal Computer challenges the
publishing world to provide high
quality at low cost, just as the
TS1000 challenges other computer
Bob Rettew, Derry, NH
Medical science utilizes T/S
power in a joint venture between
MIT and Harvard Medical School,
according to Stephen Burns, techni¬
cal director of MIT's Biomedical
Engineering Center. Burns teaches
a course called "Biomedical Instru¬
mentation Electronics" to both Har¬
vard medical and MIT graduate stu¬
dents. The course comprises part
of the joint Harvard-MIT Health
Sciences Technology program, which
combines teaching of technology and
Burns and his students use the
TS1000 as a processor for acquiring
and analyzing signals from spirome¬
ters, used commonly by respiratory
therapists to measure air flow when
breathing. The TS 1000 measures
FEV1, the ratio of total expired
air volume to the fraction expelled
in the first second. Combined with
an analog device, the Timex quanti¬
fies signals from a pressure trans¬
ducer and stores them in memory,
using Zilog DMA chips.
Why did Burns choose the TS
1000 to illustrate process control?
"It's cheap, but as powerful as any
computer available, with function¬
ally complete BASIC," Burns said.
Course members designed an in¬
terface and added 2K memory using
static RAM chips. Future plans may
include implementing a PROM program
and using a large scale integrated
circuit to completely control the
instrumentation. "The Sinclair may
allow us to program this chip to
mediate data transfer and perhaps
control timing," Burns said.
Several of his English col¬
leagues use the Spectrum as teach¬
ing tools and instrument control¬
lers, Burns added.
For information about Burns'
course (HST70) or further technical
details, write to Burns at MIT,
Biomedical Engineering Center, 18
Vassar St., Rm. 20A-119, Cambridge,
MA 02139. SYNTAX hopes to publish
With Battery Backup $109. i^IT
“’ X119. 95
ASSEMBLED & TESTED $149.95 “ KITi
With New SMART , Menu Driven SOFTWARE
•Send and receive Programs by Phone
•Copy Information into memory from a Host
Computer (such as CompuServe), Print it,
Review it, Save it on Tape, Send Text from
•Use Timex 2040 Printer or Any RS-232 Printer
•RS-232 Printer Port provided.
•No extra memory Required, But with 64-K
Memory You Can Store Up To 60 Full Screens #1
COMPUSERVE PACKAGE WITH 5 FREE HOURS ONLY $39.95 ;
$59 ■KIT In Stock!
ASSEMBLED & TESTED $69.00
• 8 Independent Relays
(with LED status indicators)
• 8 Independent TTL Inputs
(with Schmitt trigger buffers)
$119. ASSEMBLED & TESTED
the “ULTIMATE MEMORY
• Battery Backup - Computer and full 64-K Backed
• PROM/ROM socket
• Reset Switch-Reset without destroying Program
• BYTE-BACK EXCLUSIVE FULL 64-K
The 0-8K area is available. You can execute a copy routine (provided) to
copy the TIMEX ROM into the 0-8K area of RAM then flip a switch and you
have your operating system in RAM. You can modify it and create your
own customized operating system. Full details, examples & proqrams
WHY PAY MORE FOR LESS FEATURES?
GET THE “ULTIMATE MEMORY”
BYTE BACK S UM-64
NEW ZX PRO/FILE
Clearly the Best File Management Program Available.
S This New Program is what the Timex has been waiting for. %
At BYTE-BACK we have used & evaluated almost every data organizer & Data File Program on
the market & we were not really impressed until we tryed Thomas Woods’ NEW ZX PRO/FILE
Program. It is truly the best piece of software we have seen for the Timex Computer. We now use it
to help run our business. This program is so FAST that even when the program is full the file you
want is on the screen within a second.
The ZX PRO/FILE has features not found on the other Data File programs. It has: FILE
ANALYSIS function which allows you to count, analyze frequency, %, etc. Capability to create
FILES OF ANY SIZE in the same program MULTIPLE WORD SEARCH, excellent ADD/EDIT
features. ORDERED FILE OUTPUT based on any numerical value contained in the files
DEFINABLE PRINTER FUNCTIONS & AUTO SEARCH. Works with both 16K & 64K memory
FREE 59 page BOOK. This book alone is worth the purchase price. ZX PRO/FILE’s machine
language concepts & methods are fully explained. It includes a complete PROGRAM LISING &
detailed explanation of how the program works & how it can be easily modified. It also includes a
machine language programming section.
• By using a single POKE command you
can change and latch the status of each of
the 8 relays.
• Your computer can read the status of all 8
inputs by the use of a single PEEK
• A comprehensive manual is included that
has complete application details.
• More than one BB-1 can be used at a time.
16 K MEMORY UM-16 $59.95 kit $69.95 assembled & tested
Battery backup, reset switch, PROM/ROM socket PLUS...
1 year, 100% trade-in credit towards the UM-64.
RS-232 Module $59. 95
ASSEMBLED & TESTED $69.95
Drives the Gorilla/Bannana & Other Serial Printers
ALL MODULES CARRY 90-DAY WARRANTY
TRY BYTE-BACK MODULES FOR 10 DAYS WITH NO OBLIGATION
Prints on Standard Paper. 80 Columns
Specify Serial or Parrallel.
See “Leadina Edae” Ads
Discounted to only
byte-back KEYBOARD $59.95
We use the same key switch found in
the expensive computers such as:
Hewlett Packard, Texas Instruments,
Atari, D.E.C. etc. The multi-colored key caps are the
same type used on the IBM Personal Computer, but with
the TIMEX legens. EXPERIENCE QUALITY
Shipping and Handling $4.95 ■=
ORDER PHONE (803) 532-5812 ZX
ITEMS ORDERED: _
Bill My □ Am. Exp. □ Visa □ M/C
Exp. Date _Card No. __
Dealer Discounts Available
MailTo: BYTE-BACK CO. pvsssFl P***
Rt. 3, Box 147, Brodie Road \ fV- JSmm
Leesville, S.C. 29070 -
POKE DOWN AND ABBREVIATED SAVE/LOAD
With a 16K RAM pack, you can't
help but notice longer SAVE and
LOAD times compared to a IK or 2K
machine. And when a program writ¬
ten with extra memory attached is
published, it is often listed as
16K, regardless of its true length.
To avoid both problems, try
this: Before starting a program,
execute (without line numbers) POKE
16389,68 and NEW. No matter what
your RAM, this process makes RAMTOP
17408, or IK. (The other value
used to determine RAMTOP at address
16388 is always 0 unless otherwise
With the computer now limited
to IK, begin writing. If your
program fits and runs, it is a IK
routine. If IK is not enough and
you have more than IK attached,
SAVE what you have. Now POKE
16389,72 and execute NEW. Load
your SAVEd program. Your computer
now has 2K (with 16K you can unplug
or POKE 16389,128 to restore 16K).
What if you already SAVEd your
program using 16K? For sure it
will not LOAD into less memory.
So, LOAD it into 16K. Then execute
CLEAR and PRINT PEEK 16396+PEEK
16397*256. If the number displayed
is under 17408, the program fits
into IK; under 18431 fits in 2K.
Of course, just because it
fits doesn't mean it will run. IF
you RUN it and PRINT PEEK 16412+
PEEK 16413*256 still yields a num¬
ber under 17408 for IK or 18431 for
2K, it probably will run in that
memory. The only way to know is to
LOAD it into IK or 2K and RUN.
This requires making a IK or
2K SAVE from your present 16K ver¬
sion so you can LOAD it into lesser
memory. With the 16K version LOAD-
ed, execute CLEAR and POKE 16389,68
for IK or POKE 16389,72 for 2K.
Then SAVE. You now have a IK or 2K
SAVE. Now execute NEW to set the
computer to the limited memory,
LOAD the just-saved routine into
the smaller memory and RUN.
As you do this procedure, you
surely notice the shorter SAVE and
LOAD times. You can abbreviate a
SAVE to include just the program
portion of any length routine by
executing CLEAR then POKE 16388,
PEEK 16396 and POKE 16389, PEEK
16397 then SAVE. The resulting
shorter SAVE loads into 16K just as
quickly as it SAVEd. After the
SAVE, unplug or POKE 16388,0 and
POKE 16389,128 to restore 16K.
Rolf L. Miller, Ventura, CA
Test your archery skills and
learn some fundamental physics at
the same time. ARCHER simulates
the effects of gravity, angle and
velocity on bow-and-arrow trajec¬
tory. Type in the program and RUN.
Decide how many arrows you wish to
shoot (the fewer tries, the higher
the score if you hit the target).
ARCHER tells you the target dis¬
tance, which varies from round to
round. Then input the angle and
velocity you think necessary to hit
the target. Angles must fall be¬
tween 15 and 89 degrees, and veloc¬
ity between 50 and 99 feet per
second. Enter these together;
i.e., 5060 for angle of 50 degrees,
velocity of 60 fps.
ARCHER next draws your target,
and shoots your arrow with a TWANG.
It must land within three feet of
the target. (On-screen, the num¬
bers represent the target.) In the
following example, our assistant
editor scored a bullseye.
The computer calculates the
yardage you over- or undershot, and
lets you try again until you use up
your arrows. You can play as many
times as you like, and many people
DRUGS & BUGS
An Antibiotic Selection Program
For Physicians On Tape
• Fa* • EdteaitoiraaD
Send name and address with $39.00 to:
William D. Loeser, M.D.
1871 Coronado Ave.
Youngstown, Ohio 44504
can play; ARCHER lists the high
scorer as the score to beat before
each player's turn. ARCHER prints
the cumulative score at the end of
each round. (ARCHER does not list
individual scores for rounds? you
must subtract previous scores to
get separate round totals.)
G=acceleration of gravity (fps)
N=number of arrows chosen
D=target distance (yds.)
Sl=scaled down distance
B$=angle, velocity input
A=angle (convert to radians)
R=arrow travelling distance
Tl=loop end value
Kl=factor to plot X-axis
K2=factor to plot Y-axis
K3=factor to plot Y-axis
X=X in plot statement
Y=Y in plot statement
SCORE=score of round
Z$=response to prompt
Lafayette Bagley, Los Angeles, CA
VENDOR REPORT AND NOTES
Barlog Software will not offer the
64K RAM module kit as announced in
SYNTAX (Jul.83 p.2). Assembled
RAMs are still available. Barlog
Software, 401 N. Geyer Rd., Kirk¬
wood, MO 63122.
Free MC wall charts are no longer
available from Henri Poche, as
listed in SYNTAX (Feb.83 p.2).
Contact Henri if you did not re¬
ceive one and want a refund of your
35c postage. Henri Poche, 5751
River Rd., New Orleans, LA 70123,
ZX PRO/FILE manuals are delayed
until early August due to printer's
illness, reports Tom Woods. Con¬
tact Tom at POB 64, Jefferson, NH
Biocal Software offers replacement
tapes to anyone who purchased un-
loadable tape from them before
April, 1983. BIOCAL says it cor¬
rected the problem with equipment
upgrades. Send bad tape + $1 P&H
to receive updated documentation,
and program on BASF Data-Trac tape.
Contact Biocal at their new office
at 167 Wilson St., Petaluma, CA
94952, 800/237-8400 x70.
Quicksilva Ltd. of Southampton, UK
announces the opening of a US of¬
fice to handle North American
Quicksilva software manufacturing
and marketing. Quicksilva, Inc.,
426 W. Nakoma, San Antonio, TX,
Memotech's RS232 interfaces, back¬
ordered since Mar., are now avail¬
able for $99.95 and in plentiful
supply in the US. Memotech also
introduces a new direct-connect
modem, $149.95. Package deal:
RS232 (includes communication soft¬
ware), modem, cable plus two hours
on CompuServe, $199.95. Memotech,
7550 W. Yale Ave., Suite 220, Den¬
ver, CO 80227, 303/986-1516.
Many new peripherals for ZX/TS
computers now use I/O addressing.
Why? Two main reasons: add-ons
already use most "good" memory
areas, and even 2K machines can
access I/O devices, making them
usable without extra memory. This
helps reduce costs significantly.
But because I/O manufacturers
keep costs low, they must rely on
partial decoding of port addresses.
Z80 processors can address 256
unique I/O devices (256 inputs and
256 outputs) using lines Ag-Ay on
the address bus. Each time we fail
to use a line to decode, we cut the
number of assignable ports in half.
For example, if we do not use Ay as
part of our device, we can only
address 128 unique devices.
A7 A6 L A5 A4 A3 A2 Al A0
i-L- i .
(X = not used)
In the above diagram, we show
address 127 ,nj, or possibly 255/ D) ,
since we dorrt use Ay. Of course,
we must also use IOREQ NOT, and ei¬
ther RD NOT or WR NOT to tell the
system we are requesting an I/O
port. For any port, we must have
at least two lines in our selection
logic. To fully decode a port, we
need eight more lines, totalling
ten. This could require a fairly
expensive chip or decoding device.
To cut costs, we only choose a
few of the address lines. See the
following diagram of two currently
available I/O devices.
#1 A 7
" 15 d
Addresses: 0-31 d
You can decode these devices
cheaply, but they overlap. Prob¬
lems could develop if you attach
both devices at the same time,
unless you make sure to use non¬
overlapping addresses. Clearly, we
should not use addresses 0-15 in
the example shown. You should
select device #1 using the 64-79
area, and device #2 should use a
code from 16 to 31.
Decoding schemes for devices
#1 and 2 follow. Implementation of
this entire decoder in a single 25<(:
chip, the 74LS28 Quad OR gate pro¬
vides one big advantage. But we
effectively eliminate a large num¬
ber of potential addresses—a dis¬
advantage. In both examples, we
lose 31 possible ports to get one.
RD Device #2
Although keeping costs low by
using partial decoding schemes re¬
mains important to ZX/TS suppliers
and consumers, manufacturers should
provide port address ranges in pro¬
duct information and advertising.
I suggest you contact vendors be¬
fore you buy, to determine the
compatibility of any new peripheral
with those you already own.
Paul Donnelly, Centerport, NY
Remember that the ZX/TS uses all
even port addresses to read the
partially decoded keyboard, though
it's always called as 00FEh.—KO
CLASSIFIED ADS: Reach nearly 10000
ZX/TS users for $9/line. Send
typed copy, 35 char/ line, with
check by 15.th of month for next
month's issue. To rerun, resubmit
ad with check. SYNTAX, RD 2 Box
457, Harvard, MA 01451.
****** Keep medical records
* FAMILY * of family members -
* HEALTH * Doctor Visits, Shots,
* RECORDS * Perscriptions, & more!
****** i 5 K & 64 k versions.
$12.95 (.83 NY tax) PYRAMID SOFTWARE
Box 813-1, Pearl River NY 10965
Into Algebra & Graphs? 16K program
graphs and solves most algebraic
equations. Send $3 for explanation,
listing & cassette to Fraser-Smith,
3431, W. Dickens, Chicago, 60647.
++++++++++++ OUICKDRIVE +++++++++++++
!!Accelerate your 16K ZX81/TS1000 ! !
10 M.C. Rout. Listable,Explained+++
DRAW,Inverse,more. ORDER NOW!! SEND
$12.95 to MICRO-LOAD/505 E.3rd.#A-5
+++++ Truth or Conseq.,NM 87901 +++++
********* M AZEBALL *********
All machine code. Seven screens.
This is a "bouncing ball" game that
makes the others look like toys!
***** TIMEBLASTERS *****
Over 3K of machine code makes this
the best of all the graphics space
wars-For serious arcade players!
***** METAGRAPHICS *****
At last you can create elaborate
pictures using over 2000 different
graphics characters. BASIC and M/C.
All cassettes run on ZX81 or TS1000
/1500 (16K RAM). $12.95(US) for 1
or $24.95 for all 3, postage paid.
Money back if you're not delighted.
******** CALLIOPE SOFTWARE ********
4130 Coe Dr. NE, Albuq. NM 87110
UN-LOCK NEW 1 LINE BASIC PROGRAM
WILL HALT AUTO EXECUTION OF M/C,
BASIC PROGRAMS,SO THEY MAY BE SAVED
FOR LISTING & INFO, SEND $5. TO C.
TRAHAN c/o SHUTTLE SOFTWARE GROUP
PO BOX 71; SEABROOK, TEXAS 77586
BUSINESS GRAPHS 6 16K programs,
9 Springbrook, Sacto.,CA95831
* * * * ROMPAK NEEDS YOU! *****
* Serious & Amateur TS Programers *
* We'll help your creation EARN $ *
* Details? Call NOW! 213-653-9741 *
* or send for confid form: ROMPAK *
* 8206 Blackburn Ave L.A. CA90048 *
*BIORHYTHMS! Charts rhythms, checks
compatibility,signals critical days
Files by name; ONLY $15.95. ALSO ZX
BASIC coding forms 50/pad ONLY 2.25
+.75P&H/pad. CAPRICORN, 25 George
St. S.,Toronto, Canada, M5A 4B1
BUDGET ANALYSIS ZX81 16Ktape$15U.S.
Includes daily+monthly budget re¬
ports. NOMIS COMPUTERS 11121 82 Ave
* 631,Edmonton,Alta.,Canada T6G 0T4
NEW LOW PRICES FOR WINKY BOARD II!
Make LOADing easy. Copy ANY ZX/TS
cassette + more! $19.95built/tested
$14.95 kit +$l.shp. Simple to use.
SOFTWARE: KEY unlocks any ZX/TS
cassette,MERGES + more $10PPD; HRP
for 256x192 res. print outs $10PPD:
ZXLR8 for 6-10x faster LOAD $11PPD
G.RUSSELL-ELECTRONICS, RDl Box 539
Centre Hall,PA16828: 814-364-1325
* PLUG IN YOUR TIMEX/ZX PROJECTS *
3-SLOT FULLY ASSEMBLED MOTHERBOARD
ACCEPTS RADIO SHACK AND VECTOR
PLUGBOARDS,PLUS ALL SINCLAIR HRDWR.
$29.95 JDC 5-14 SENTINEL RD. DOWNS-
VIEW ONT. CANADA M3M 2Y5
CHECKBOOK RECORDSBALANCER .Store 200
checks(16K).Only $3 To Scott Wolf
4949 Webster Rd,New Haven,IN 46774
*** C-FOOTBALL *** ZX81/TS1000(16K)
CALL PLAYS AGAINST ANY OF THREE
INCREASINGLY SOPHISTICATED DECISION
MAKING LEVELS OF THE COMPUTER$14.95
STARTLINGLY REALISTIC. DKN BOX 8477
ATLANTA GA. 30306
ONLY $5 per order.Send your specs.
Include memory size. To:Scott Wolf
4949 Webster Rd,New Haven,IN,46774
SYNTAX is published monthly by a wholly-
owned subsidiary of The Harvard Group.
Syntax ZX80, Inc.
RD 2, Box 457, Harvard, MA 01451. Telephone
12 issues, $29. Single issue, $4.
MY TYPE ..THE touch typing tutorial,
16K cassette, $8. (ZX-TS)
BIG-KEY ..Dry-transfers in red&blk.
LEGENDS for std. keycaps. $7./set.
790-B E.Big Beaver Troy Mi. 48084
Publisher: Kirtland H. Olson
Editor: Ann L. Zevnik
Assistant Editor: Lisa Fass Vivat
Technical Consultant: Richard Kelly
© Syntax ZX80, Inc., 1983. All rights reserved.
Photocopying prohibited. ISSN 0273-2696
OUR POLICY ON CONTRIBUTED MATERIAL
SYNTAX invites you to express opinions related to any Sinclair computer or
peripheral, or the newsletter. We will print, as space allows, letters discussing items
of general interest. Of course, we reserve the right to edit letters to a suitable length
and to refuse publication of any material.
We welcome program listings for all levels of expertise and written in either
Sinclair BASIC or Z80 machine code. Programs can be for any fun or useful
purpose. We will test run each one before publishing it, but we will not debug
programs; please send only workable listings. Programs submitted on cassette can be
tested more quickly and with less chance of error.
In return for your listing, we will pay you a token fee of $2.00 per program we
use. This payment gives us the nonexclusive right to use that program in any form,
world-wide. This means you can still use it, sell it, or give it away, and so can we.
We will consider submissions of news and hardware or software reviews. Please
keep articles short (350-400 words). Again, we reserve the right to edit accepted
articles to a suitable length. We will pay 7 cents per 6 characters, including spaces
and punctuation, for accepted articles.
When you send in programs for possible publication in SYNTAX, please
include the following information:
• How to operate the program, including what to input if it does not contain
• Whether you can run the program over again and how.
• How to exit the program.
• The Syntactic Sum (program published in Feb. 81 and Jun. 81; send SASE
for a free copy).
• What RAM size program requires.
• What ROM program uses.
We pay for this explanatory text at the same rate as for articles in addition to
payment for the program itself.
If you want us to return your original program listing or article, please include
a self-addressed, stamped envelope. Otherwise, we cannot return submitted material.
FULL TEXT EDITING-EASY TO USE. TAB,
BLOCK SAVE,AUTO TEXT ALIGN,ZX/TIMEX
PRINTER. $11.95 TAPE-BOB FINGERLE
BOX 7793, FREMONT CA 94537-7793
**** TECHNICAL APPLICATIONS ****
Software for electronic CAD and
formulas. All in BASIC, on tape,
with comprehensive instructions.
Send SASE for a list of programs
and prices to: SofTec, P.O. Box
432, Fairport, New York 14450
AIRPLANE INSTRUMENT FLIGHT SIMULAT¬
OR program.VOR,DME,ADF RADIOS. MAP
sette for Timex 1000,16K computer.
Send $12.95 to Amanda Systems,
P.O. Box 118, Holmdel,NJ 07733
#*#*# DISCOUNTS #*#*#
TS2000 Color Computer send SASE
2040 Printer $93;paper 3/$6,24/$44
SEIKOSHA printer pkg $319; 80 col¬
umn printer $185?Plug in kybd w/
space bar $66;FASTLOAD $12;MUCH
ware.For IMMED. UPS del,send checks
to:SIMPLY SINCLAIR Box S Wdbg.,VA
22194 MC&Visa call (703)690-3798
Fill out the coupon below and mail it to: SYNTAX/SQ, RD2 Box 457,
D My check is enclosed. □ Please charge my □ VISA
Make checks payable to:
SYNTAX ZX80. Inc.
EH Diner's Club P American
Express □ Mastercard
P Carte Blanche account
Harvard, MA 01451 t s883
YES! Please send me:
P The Combination II (13 issues of SYNTAX and SQ Winter
P The Catch-up II (SYNTAX Jan. 82-Jan. 84, SQ Winter 82-
Summer 83, plus 1 binder) .$77
Exp date --_Bank number (MC only)
□ The Works II (SYNTAX No. 80-Dec. 83, SQ Winter 82-
Summer 83, plus 2 binders).$97
P 12 issues of SYNTAX.$29
□ 3 issues Syntax Quarterly (Winter 82-Summer 83).$25
Day phone ( )_Evening phone ( )
□ My subscription number is:_
□ This is a new subscription.
P 1 issue Syntax Quarterly P Winter 82 P Spring 83
□ Summer 83.$9
□ 1 Binder.$9 P 1 issue of SYNTAX.$4
Telephone orders call
These offers expire 30 Sept. 83—SUBSCRIBE NOW.
****** FAST LOAD/SAVE PROGRAM *****
* >>> Z-XLR8 (Z-accelerate) <<< *
* A Software Based Tape System for*
* 16K ZX81 & TS1000. 6-10 X Faster*
* LOAD/SAVE. Create Program, Data,*
* Binary,& Graphics Files. Z-XLR8 *
* Takes < 2K RAM & is Completely *
* Relocatable! No Hdwre Additions!*
* Cassette $11.00 ; EPRO $21.00 *
* ADVANCED INTERFACE DESIGNS *
* P.O. BOX 1350 *
* STATE COLLEGE, PA 16801 *
FREE SOFTWARE BROCHURE - Send SASE.
HOUSEHOLD BOOKKEEPER*CALENDAR PLAN-
NER*SYNC INDEX*BIO-RHYTHMS*KEY COL-
LORS- LISTINGS $3 CASSETTE'S $7.95
I.M.S. Box 4503 Lancaster,Ca. 93539
ALARM! ZX81 BECOMES $1000 BURGLAR/
FIRE SYSTEM, CASSETTE & INFO $29.
SOFTSKID BX 5097 GREENSBORO, N.C.
ZIP 27403. PIANO, MUSIC PROGRAM $7
5 Top Quality programs on cassette
tape, ready to load and run. Only
$5.00. Send no money now. Send a
Self-addressed stamped envelope to:
Original Programs, 3763 W. Crocus
Dr. Phoenix, Arizona 85023
COMPUSETTE is a Norelco-boxed and
labeled C-10 cassette which is
especially designed for micro¬
computer application by TAPEMASTERS
25 for $20.00 100 for $70.00
COMPUSETTE+ is a C-20 cassette
25 for $22.50 100 for $80.00
COMPUDISK is a SS, DD, Soft Sector
5 Yh In. Disk 10-$23.00 50-$110.00
VISA MASTERCARD C.O.D.
TX 214-349-0081**OTHER 800-527-1227
10% Discount for Check with Order
PO Box 38651W Dallas, Texas 75238
FREIGHT PREPAID*DEFECTIVES REPLACED
Ramdisk for $12.50? Its MICRODRIVE !
Use & store 8 FULL 2K progs AT ONCE
in 16K: fastsave, autoload, instant
access, all MC. BAFFLEBALL ! Fastest
MC 2K arcade game ever, $5.50. FREE
PROG & CAT: SASE to RHEESWARE, 4001
Pennwood #3, Las Vegas, Nev. 89102
*** HALF-PRICE SALE ***
TOTAL YOUR ORDER & SEND ONLY HALF
PREDICT NFL GAMES
PICK 1 EM. 19.95
ANIMATED ADVENTURE FUN
CAVES OF ZULU. 19.95
HELP WITH DECISION-MAKING
MULTI-ATTRIBUTE ANALYSIS. 19.95
ORDER FROM STUART SOFTWARE 25381-G
ALICIA PKWY STE 316 LAGUNA HILLS CA
92653 ADD 2.00S/H PER ORDER VISA/MC
*** (714) 855-4753 ***
Bolton Road, Harvard, Mass. 01451
CSwrA Permit No.8
rirsf Class 0i45i
HR WILLIAM TOMLINSON
3635 RIVEREDGE DRa
JACKSONVILLE > C L 322