1^92 HOLIDAY X S S OE
13 - 15
21 - 23
A Plea For Assistance
Bill Pedersen Writes (2068)
Epson 9-Pin Printer Enhancements
IBM / SPECTRUM Emulator (part 2)
IBM/SPECTRUM Emulator (part 3)
2068 BASIC Tutor
ZX-81 Resources - Joystick
1992 QL Library
SINC-LINK Contents (Indexes)
SPECTRUM Mods to US Standards
Use Less RAM By Typing More (2068)
Computer Classics Advert
TIMEX- SINCLAIR USERS CLUB
NOV - DEC '92 VOL lO - 6
SINC-LINK IS A PUBLICATION OF
THE TORONTO TIMEX-SINCLAIR USERS
CLUB AND IS ISSUED 6 TIMES A
YEAR. CLUB MEMBERS RECEIVE FREE
COPIES AS PART OF THE $20. 00
ANNUAL MEMBERSHIP FEE.
NEWSLETTERS ARE EXCHANGED, FREE
OF CHARGE, WITH OTHER
TIMEX-SINCLAIR USERS GROUPS.
PLEASE CREDIT THIS PUBLICATION
AND THE AUTHOR IF YOU COPY
THE TS2068 & ZX-81 GROUP MEETS
ON THE FIRST WEDNESDAY OF EACH
MONTH AT 14 RICHOME COURT,
SCARBOROUGH, ONT. 7PM START.
THE QL SIG WILL MEET WEDNESDAY,
NOVEMBER 18TH AT 586 ONEIDA
DRIVE, BURLINGTON, ONT. 7PM
START. DECEMBER DATE TBA.
SINC-LINK IS PRODUCED ENTIRELY
ON SINCLAIR AND TIMEX-SINCLAIR
SEND CORRESPONDANCE TO:
Attention: SINC-LINK EDITOR
TORONTO TIMEX-SINCLAIR USERS
CLUB, 14 RICHOME COURT,
CANADA M1K 2Y1
( Out-of-town members )
mm mm n
(Area Code 416)
RENE BRUNEAU ( 531-9749 )
BILL LAWSON ( 444-8772 )
GEORGE CHAMBERS ( 751-7559 )
LOUIS LAFERRIERE ( 820-3725 )
HUGH HOWIE ( 634-4929 )
JEFF TAYLOR ( 244-8583 )
GEORGE CHAMBERS , 14 RICHOME COURT,
SCARBOROUGH. ONTARIO. M1K 2Y1
( 416-751-7559 )
TORONTO TIMEX-SINCLAIR USERS CLUB
Well, a few things have happened since last issue. Pres Rene Bruneau's family
and the Taylor family made our respective ways to the Computerfest in Dayton,
Ohio at the end of August. Rene and I decided that we wanted to see what kind
of Timex-Sinclair exhibits were still being put on these days, not to mention
the fact that we were both anxious to visit the USAF museum out at Wright-
Patterson Air Field. We weren't disappointed. By the way, the Taylor family made
the trip from Toronto to Dayton in just 7 hours, moving at slightly faster than
the speed limit. So for those of you thinking about making the trip next year,
it's not that far. A little over 400 miles.
At the Fest we met such notables as Don Lambert from ZXir QLive Alive fame,
Bill Pedersen from WIDJUP, Frank and Carol Davis from Update Magazine and his
Mechanical Affinity partner, Paul Holmgren. We missed making connections with
the SMUG folks who were there with a table of stuff but were never there when
we visited. Mechanical Affinity had a good selection of T/S bits at their large
table and Update was offering a lot of documentation.
Later Saturday evening Rene and I met Bill and Frank and we discussed various
topics about T/S computing well into the wee hours. Bill also demonstrated some
of the hidden features of the TS2068 and explained why areas of the ROM have been
masked. He also showed us a few features of his CAD program for the 2068. Very
For members looking for lots of new Timex-Sinclair products, the trip might
be disappointing. But if you have interests in other computers as well, then
the trek down to Dayton may be justifiable. And the museum is definitely worth
visiting. I know I'll be back next year.
The November club meeting will be our last at Forest Hills Collegiate. The
difficulties in access to the school, to parking and to getting all our gear to
the new classroom (up and down several flights of stairs) have necessitated a
change in venue.
Starting in mid-November, the QL SIG will be meeting at Hugh Howie's home in
Burlington about every month to 6 weeks. The TS2068 and ZX-81 types will continue
to meet on the first Wednesday of the month, but at George Chambers home in
Scarborough. Both places are easier to get to than the school, have adequate
parking and both have the advantage of not having to move equipment about for
demonstrations. See the blurb on the inside cover for times and addresses.
All the existing members have agreed to continue in their respective capacities
except for Rene who will be away on an intensive programmers course for the next
few months. In his absence, I will act as interim Pres until he returns. We had
an executive meeting in late October at my place to discuss the changes to
meetings, course of action and an interesting mailing experiment. More on that
P.S. Check out the plea next page. Jeff Dodds came to our meeting last month
and asked for assistance. Can you help? That's all for now... J.T.
Plea for Assistance for the Disabled.
Apart from being a member of QUANTA, I'm also a member of a voluntary organisation
called REMAP. REMAP stands for Rehabilitation Engineering Movement Advisory Panel,
and we work with local occupational therapists, looking at the needs and desires of
the disabled in the community and advising on what aids are available and/or suitable.
Where nothing quite fits we try to design something.
Most recently we have been dealing with residents in a Home for the Disabled, several
of whom are more or less paralysed from the neck down.
These people have the same needs as everyone else. They need to eat, they like to
read, they have itches to scratch and a myriad of other things to be done. Unlike you
and I though, these things have to be done for them. I know there are things to do
all of the above, but they are expensive and individual. You require one item for
each of the above functions, each requiring space where space is often at a premium.
I am trying to design a voice-controlled robot arm to do all of the above things for
Back home I can buy ZX81 mother boards for about $30, and I can build an arm using
stepper motors for less than $100, so a ZX81 controlled arm is well within the bounds
And now, the appeal. Back in the early eighties in Britain, a firm known as William
Stuart Systems Ltd., produced a black box and some software for use on home computers
of the day. ZX81, Spectrum, Atari, Amstrad, Pet, Philips, etc., The package sold for
about $100, as "BIG EARS", and provided a voice-controlled cursor on screen. The
company has now closed down and can't be traced.
So if anyone out there has heard of ,!BIG EARS" or its equivalent on this side of the
water, if anyone has the package languishing in attic, garret or dungeon, PLEASE?
PLEASE, PLEASE get in touch with me.
By the time this is published I'll be back home where I can be reached at the
following address :-
J. R. Dodds
87/53 Pennywell Gardens
Mr. Jeff Taylor, Editor
Toronto TIMEX-SINCLAIR Users Club
335-75 Lemonwood Dr.
Islington, Ontario M9A 3L4
I was happy to meet you at Dayton. You are the only Toronto members I
can remember meeting except for Larry Crawford, but then, my memory is not
that good anyway, as you might have noticed.
The (to scale) EPSON Printer graphic you could not XEROX was a XEROX,
and a poor one at that. A direct hi-rez printout is enclosed.
Because the graphic uses very narrow lines, it might seem that they are
too light to copy. Unlike DRAFT mode, individual dots are connected. Good
XEROX copies can repeat this fine detail without darkening, though some can
improve general appearance. (It was printed using a 24 pin printer and HP
graphics language from ASCII files.)
I had meant to do the same for 24 pin printers, but doing an honest job
requires six pages; and even then, organizing them in a clear manner
requires quite a bit of supporting text.
In the same vein, it is actually possible to get 360 horizontal dots
per inch on an FX80 using multiple passes and intermixing character and
graphic modes. Explaining how this is done in print — forget it! It
involves printing blanks using PICA, backspacing using ELITE, and then going
to a graphic mode for one example. Because added resolution using six
passes does not appreciably improve CAD, it was not used.
With a humungous amount of work I can capture screen images which
happen to contain gray-scale windows from a multimedia encyclopaedia.
Getting these onto a TIMEX-SINCLAIR disk isn't easy, nor would copying a hex
printout by hand. That is why I'm looking forward to getting a file from
you containing A2D encoded pixel data along with a simple description of how
the file is encoded and what it portays.
As with CAD, different printers work best with particular methods of
"dithering" and gray levels. The same applies to screen video modes. The
TS2068 is most amenable to 4x4 pixel "gixels" giving 17 shades. That
requires a file 4 bits "deep", that is, 4 bits per pixel usually packed two
pixels per byte. An uncompressed TIFF file is often exactly this format.
TV pictures can be quantized in many different ways, but what is nearly
universal is real-time sample intervals integrated and then converted to
digital form as scanning continues. These digitized samples are usually
blocked by scan line and field. Two fields comprise one frame. One full
interlace frame contains 525 lines, only about 400 represent picture data.
The rest are border, vertical retrace, color burst and sync pulse templates.
The TS2068 has 192 non-interlaced scan lines of data out of 262. The
horizontal scan frequency is exact, but the vertical is fast by 525/524, not
enough to bother.
A single field with 256 samples per line would supply enough data for
16 screens of panned dithered display or dot matrix dump output. It would
also fill a landscape oriented printed page. Fewer samples per line could
be used, but then dithering routines have to integrate samples from two or
more scan lines for each gixel.
For best results, no fewer than 128 samples per line should be used
with no less than four bit gray resolution. The absolute minimum is 64
samples per scan line at 3 bits per sample. Anything less yields strictly
amateur results by comparison. More gives an opportunity to correct for
factors like overexposure and printer "gamma". Gamma is a correction factor
which can make the screen and the printed page look identical viewed side by
Round dots, whether from pin impacts or ink droplets have difficulty in
registering near-black detail. Dots overlap long before they completely
cover the area. One common partial cure is to re-define a square array of
four almost obliterating dots as a single pixel before creating gixels. A
very few printers actually have square pins.
When round dots must be used, and only 17 gray levels (nonlinear) are
used per gixel, samples 6 to 8 bits deep can be mapped using a pallet to
correct for nonlinear ity.
Other problems exist for printers with different sizes of pins, pin
spacing, and dot pitches. Some laser printers operate like they have nearly
square dots, too. A few special tests can determine that.
In spite of the complexity of visual presentation, the computer can do
near miracles when given enough data. Programmers should never forget that
taking convenience short-cuts is hazardous to results. This is especially
true when learning about what is being done.
If I can, I plan to come out with my own DOS some time next year. This
development will apply to all TS2068s and clones wherever they are. It
all hinges on getting my ROM BYPASS to work like the TIMEX BEU without
having to open the case for modifications.
In case LARKEN faithful are worried, just don't change a thing. Of
course they won't be able to use expansion bus bankswitching because both
LKDOS and JLO SAFE wrest priority from the operating system. I have not
yet found a suitable way to negotiate this difficulty, descended from
Interface 1. I surely don't want to propagate that problem to still another
tier. If others try to merge the systems I advise caution and realization
of the consequences of good intentions.
Hangin' in there, baby,
i — i
s c <
$ > E
V/ \^ \^ \~S S^ W
/^n /~\ /-\ A A A ^ ^
Q L I P S
by Hugh Howie
CHUCK QUILL OUT? NO S I R R E E
Each new word processor to come on the market is extolled to
make the use of Quill obsolete. These statements are mere
ramblings and ravings of the producer of this new "ya gotta
have this" item just to make you rush out and buy this new
and improved and out of this world word processor.
I am using Quill to write this letter to-day, and I have to
admit I can not do as fancy a job as with ray regular word
processor. But then again, I cannot use my regular word
processor on a plain jane 128 K QL either. Most of the new
w/p's require quite a bit more than 128 K to operate, and
those that might be able to fit into the standard QL do not
leave much if any, room for the document.
Another little thing the producer of the new W/P tells you,
is that the new W/P retains many of the Quill key press
functions, so there is not all that much to relearn.
You will also note that those new W/P 1 s do not replace each
other, they are supposed to replace Quill. Why is everyone
so down on Quill?
Compared to many W/P's Quill is very easy to use and does not
require a long learning period. You can sit down and write a
letter with Quill with only a few minutes study, and still
make an acceptable job of doing so.
It is also the one Word Processor that each and every QL user
has in common. We ALL have it, and we are all capable of
writing with Quill.
Every programmer uses Quill to write the explanation of how
his/her program operates. This is because the programmer
KNOWS that we all have Quill. What a great honor it is to be
recognised as being so popular.
Every new W/P has the facility to import Quill as a QUILL_DOC
Quill has been in use for about eight years, that's right,
count them! And they are still trying to replace it!
I must admit that those new W/P's are really nice to work
with once you learn the intricasies of their use, but we
still need our old stand-by Quill, so why not use it.
Write to this Newsletter to-day, right now. USE QUILL. The
only Word Processor that is common to ALL QL users.
CHUCK QUILL OUT? NEVER
Quill is still being used by programmers for their doc files,
and I am using QUILL to write this article. Not bad for a
program some are trying to replace, EH?
Ronald M. Cavin II
1741 Marshlyn Ct .
Columbus, OH 43220 U.S.A.
I hope some of our readers found the last article
interesting! I've found this venture fascinating. I'll try to
keep going as long as the readers want. I believe this may
breathe some much needed new life in our little boxes.
Enough preliminaries, on with the show. As I mentioned
last article, we now need to transfer our copy of rom from the
Spectrum to the IBM. If you read the issues of SINC-LINK as I
suggested, you're probably way ahead of me. However, for those
who didn't, for whatever reason, we'll briefly cover this
What you will need is an appropriate RS-232 cable, a NULL
MODEM, and terminal software for both computers. Again, let me
recommend Rene Bruneau ' s work in the NOV-DEC '91 issue, and Bob
Mitchell's letter in the MAR-APR '92 newsletter. These two
readings will provide you with much more detail than we
intended to enter into during this series. However, if there is
enough demand for these particulars again, I'm willing to set
them out on paper.
As I said last time, my IBM has an internal 2400 baud
modem. Attached to the Timex is an AERCO version of the Z-SIO
card. Thus my transfer rate is limited to 1200 baud! I am using
MAXCOM, by Larry Kenny, on the Timex, and a program called
Telix, written by one of your fellow Canadians, on the IBM.
Connect the computers, placing the NULL MODEM between
them. Start both terminal programs, making sure each machine is
set correctly in software, i.e. COM port, baud rates, UART
setup (8/1/N) , and XMODEM protocol. Be aware that XMODEM will
add 128 bytes to your transfers! Thus, when you look at the
file size on the PC, it will be 16512 long! This phenomenon is
not new! Normally this doesn't mean much. However the Spectrum
emulator program JPP-B2.EXE expects to see a file EXACTLY 16384
bytes long. We'll have to do a little editing on the file.
Start your transfer! Tell MAXCOM to send (headerless) , and
the IBM to receive SPECTR.C1. You should observe some type of
visual confirmation that the transfer is in process. On my
setup, MAXCOM displays a (+) character for each block sent,
while Telix has a large status box which show the bytes
received, CRC errors, etc. Once the transfer is done, both
computers will indicate so. Maxcom gives a screen message,
while Telix gives both visual and audible indicators. Before
next issue, see if you can locate a Hex editor for your IBM.
Ronald M. Cavin IT
1741 Marshlyn Ct .
Columbus, OH 43220 U.S.A.
By now I would expect that many of you IBM-TIMEXERS have
obtained a copy JPP.EXE. We will fire it up by the close of
this article. So lets go!
We left off last time at the termination of the rom
transfer. Somewhere on your IBM you should have a file called
SPECTR.C1, which is a image of the Spectrum rom. Also remember
that the file will be 128 bytes larger than we want, i.e. 16512
rather than 16384. Since the emulator expects to see an exact
image, we will have to delete the extra bytes. Without doing
this the emulation program will never work!
Let's get rid of this excess baggage! I suggested you
obtain a HEX editor for your clone to make this easy. Some may
want to use DOS DEBUG, but I prefer a little program called
HEXED IT . It is only program I've found that allows you to
easily delete and insert bytes in these type files. (For those
who didn't know, I have provided George Chambers with a copy of
ALL the files I have mentioned in these articles, with the
exception of MAXCOM. I don't think he would have a problem
providing you a copy if you ask him.)
Call up your editor, and using the appropriate commands,
GOTO the files' absolute location 16383. This should be a 3C in
hex format. Following this byte should be 128 bytes of 2QH,
caused by the XMODEM protocol. DELETE ALL THE BYTES FROM
LOCATION 16384 THRU 16512! This will leave you with a file
16384 bytes long. How nice! Save it to disk. NOW RENAME FILE
FROM SPECTR.C1 TO SPECTRUM . ROM . Create a subdirectory, by the
name of SINCLAIR, and copy JPP-B2.EXE and its associated files,
along with the file rom image into it.
Just a little more work before the moment of truth. There
should be a file in your SINCLAIR subdirectory named PATH.JPP.
Use an ASCII text editor and make the two lines read like those
be 1 ow :
*.SNA - . ; C:\SINCLAIR
*.R0M - . ; C:\SINCLAIR
Save this file under its original name i.e. PATH.JPP. Now, for
the moment you've been waiting for. Make sure you are in the
SINCLAIR subdirectory, type JPP and hit ENTER. What you should
have is a message like the one below:
JPP beta, built 19/03/92 20:39:56 mail bug reports etc to
arnt@swix . i f i . unit . no
Using "c:\sinclair\spectrum.rom" as ROM image
Press any key to return to emulator
Hit the ENTER key and watch him fly! ! the F12 key will return
you do DOS. We'll try to get a program going by next issue.
QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL
MY PURPOSE IN WRITING IS TO TELL YOU ABOUT THE PROBLEMS
'CHALLANGES' THAT SEEM TO HAUNT MY QL. I BELIEVE THAT LIVING
ON THE 18th PLOOR OF 22 STORY BUILDING HAS A LOT TO DO WITH
IT. FOR EXAMPLE. THIS ATTEMPT IS THE FOURTH AND THE ONE THAT
HAS PROGRESSED MOST, IN WORDS TYPED AND SAVED. TWICE THE
CURSOR DISAPPEARED AND THE MACHINE LOCKED UP. THE THIRD TIME,
WHEN RELOADING THE PROGRAM, I GOT A READ /WRITE FAILED
MESSAGE. I GAVE UP AND WENT FOR SUPPER.
THE PHOTO WAS TAKEN IN JUNE. I WAS WORKING WHEN, ALL AT ONCE
THE MONITOR BLINKED. THE START SCREEN APPEARED FOLLOWED BY
THE WINDOW OF LARGE PRINT, OR SHOULD I SAY SUPER LETTERS tc
DIGITS. THE SECOND PHOTO (NOT SHOWN) INDICATED THAT THE
INFORMATION, IN THE WINDOW, WAS CONTINUALLY CHANGING. I SHUT
THE EQUIPMENT DOWN RATHER THAN WAIT TO THE END. LATER, A
MONTH OR TWO, AT LEAST. THE SCREEN DISPLAYED, WHAT I THOUGHT
WAS 'CODE' AND SHORTLY AFTER RESETTING THE MACHINE. THE SAME
THING HAPPENED, EXCEPT THIS TIME IT ' SCROLLED' THE CODE AND I
WONDERED IF I HAD JUST SEEN THE 'ROM* GO BY. I'VE BEEN MOVING
STUFF AROUND AND HAVE MADE MANY SAVES AS WELL AS TWO
PRINTINGS AND WE'RE STILL GOING STRONG. DO YOU THINK IT'S THE
BUILDING??? CONTINUED NEXT PAGE.
QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL QL
ANOTHER CHALLENGE THAT OCCURS FROM TIME TO TIME IS DOUBLE
LISTING IN THE DIRECTORY. THE SAME NAME LISTED ONE BELOW THE
OTHER. I HAVE BEEN TOLD THAT I MUST HAVE PLACED AN EXTRA
SPACE, WHEN SAVING, THAT DOES NOT SHOW UP IN THE LISTING. I
HAVE TRIED TO PUT IN EXTRA SPACES BUT I'M SURE THEY ARE NOT
INCLUDED IN THE SAVE. I HAVE COPIED TO ANOTHER DISK. THEN
DELETED THE NAME AND ONE OF THE TWO REMAINS. THEN TRIED TO
DELETE THE OTHER AND AM ADVISED PROGRAM DOES NOT EXIST.
I HAVE COPIED THE DISK, TAKEN DOWN THE NUMBER OF SECTORS USED
DELETED THE FILE TAKEN THE NUMBERS AGAIN AND FOUND THERE IS
STILL SOMETHING IN MEMORY EVEN THOUGH A REQUEST TO LOAD IS
RESPONDED TO WITH PROGRAM DOES NOT EXIST.
RECENTLY, MY *_2__DRIVE BEGAN TO ACT UP. IT DEMONSTRATED THIS
BY LISTING APPROX^ T^LISTINGS WHEN I KNEW THERE WERE 69
FILES ON THE DISK. I PROVED IT BY PLACING THE DISK IN
ANOTHER DRIVE AND REQUESTED A DIR AND GOT THE RESULT I WAS
EXSPECTING. I LEARNED FROM LOUIS LAFERRIERE THAT THE__SL I PES
FOR THE HEAD PROBABLY NEED A POLISH. SO. I SHUT THE SYSTEM
DOWN, UNPLUGED THE POWER SUPPLY, REMOVED THE DRIVE FROM ITS
CASE, REMOVED TWO SMALL GROUPS of lead connectors and two
screws. This allows the removal o-f the top board and exposes
the head mechanism. By wrapping an inch wide strip of (soft)
cloth around the guide rod, working the cloth up and down,
you remove any build up of dust etc. The head can be slid
back and forth to allow you to get at most of the guide rods.
Reassemble and test. My effort paid off immediately. One
might get the idea that he knew what he was about.
ON BOARD THIS QL IS A MINERVA ROM INSTALLED BY GEORGE
CHAMBERS. FOR A LONG TIME AFTER, WHEN THE SCREEN THAT TELLS
WHAT IS CONNECTED, i.e. CARE QJUMP TOOLKIT VER. 2.09 @ 1984
AND UNDER THAT, CUMANA DISK INTERFACE VER 1.14, WHICH was
REPEATED THREE TIMES. RECENTLY I READ ONE OF HOWARD CLASES'
ARTICLES WHERE HE EXPLAINED WITH MINERVA, ON POWER UP THE
CHECKING SYSTEM MAY PASS BY THE PARTICULAR SPOT AND EACH TIME
IT WOULD REPORT AND RECORD. MY APOLOGIES TO MR. CLASE FOR
THE TERMINOLOGY AND MY THANKS, AS I OFTEN WONDERED WHY THERE
WERE THREE PRINTINGS. BY THE WAY IT DOESN'T HAPPEN NOW?
IT IS NOTED THAT MY LAST 'CONTRIBUTION' TO THE NEWS LETTER
APPEARED IN THE JUL / AUG 1939 ISSUE. SO I WILL TAKE THIS
OPPORTUNITY TO SAY THANKS TO ALL THE OTHER CONTRIBUTING
MEMBERS, WHO HELP ME LEARN MORE ABOUT QL SUPERBASIC AND TO
THE LOCAL CLUB MEMBERS. WHO MAKE COMPUTING POSSIBLE FOR ME.
W K (BILL) LAWSON
TS 2068 BASIC TUTOR
by Warren Fricke
SCREENS is a very useful function on the TS2068 but it has a few
limitations that are well known. It has two principal uses. One is to SAVE
a screen to tape. This is explained on pages J 60 and 161, and appendix A
of the manual. From these sources we learn that....
SAVE "PROG" SCREENS, really means
SAVE "PROG" CODE 1638b, 691 2
The 6912 bytes of memory starting at address 1638b include the entire
display file and all of it's attr ibutes. Hence all characters, including
graphics and colour, are SAVEd by this procedure. We may use either of the
above two lines to do so.
SCREENS has a second use, and that is to identify ind iv idual characters,
given their screen line, L, and column number, C, as in....
PRINT SCREENS (L,C)
Usea this way SCREENS is colour blind and a bit myoptic. It can only
recognise single block characters whose code is between 32( space) and
1 27( copyr ight symbol). It cannot distinguish between inverse and normal
characters, seeing them only as normal, and it does not see graphics at
all. These character i st i cs of SCREENS can be demonstrated by the following
___ 10 PRINT "CHAR- CODE SCREENS CODE LEN "
20 PRINT "ACTER OF (L,C) SCREENS SCR."
30 PRINT " CHAR. (L,C) (L,C)"
100 FOR n - 5 TO 21
110 INPUT aS
120 PRINT AT n,1;a$; TAB 7; CODE a$; TAB 15; SCREENS (n,1);
TAB 22; CODE SCREENS (n,1); TAB 30; LEN SCREENS ( n, 1 )
130 NEXT n
This routine when RUN will ask for the INPUT of a s ingle-block character.
Any character may be entered in response: normal, inverse, graphic, etc.
The routine in turn will print out a single line of information on such
character, all of which concerns it's appearance to SCREENS*
The first two columns confirm the character that was INPUT and show it's
correct code, if it has one. Inverse characters have no code and are
assigned inverse control code 20. The last three columns show the way that
SCREENS sees this character; what character it sees, what code it assigns
to the character, and it's LENgth. This knowledge enables us to use the
function correct 1 y.
FIGURE 1 is a screen dump of the results from a number of characters
entered. The first character was a solid square made by using graphics
mode and the shifted 8-key. The second character was a solid square made
using mversed video with the space bar. The third character was made in
graphics mode using the 8-key. The fourth was a space from the space bar
lone. Note that SCREENS by the results in the last three columns, sees no
difference. In all cases SCREENS sees these characters as thouoh all were
made by the space bar alone.
Next there are some mixed normal and inverse characters. To SCREENS,
inverse and normal are both seen as normal. SCREENS cannot tell the
difference between them.
Then lump all kinds of graphics together. SCREENS does not see them at
all, because it reports them as having zero code and zero LEN, and empty
string. Go back to the solid blocks at the beginning of the dump. SCREENS
saw them all as spaces as it gave them a LEN of one. Nothing at all and
space are two different things, so SCREENS differentiates to this extent.
SCREENS and PRINT POSITION
SCREENS is used in many game programs to detect the presence of a
particular character in the PRINT POSITION. This is the block on the 32 x
2U- grid of the screen where the very next character will be printed. One of
the system variables keeps track of this for the computer because the
position constant 1 y changes as the program runs.
To demonstrate PRINT POSITION we will start with a simple common program
that does nothing more than move a player's piece, or puck, around the
screen by touching one of tne four arrow keys. We will call the program
FOUR-DIRECTION MOVEMENT. . .
10 LET 1=10: LET c=15
30 LET 11=1: LET cc=c
40 LET !=!+( INKEY$="6" AND L<21 )-( I NKEYS="7 " AND L>0)
50 LET C=C+( INKEY$="8" AND C<31 )-( INKEY$=»5" AND C>0 )
60 PRINT AT L,C;
80 PRINT "*"
90 PRINT AT LL9CC;" " AND ( LL<>L OR CC<>C): PAUSE 0
100 GO TO 30
Note that lines 60 and 80 usually appear as a single- line reading:
PRINT AT L,C;"*"
We have split it into the two separate instructions, where to print and
what to print. The reason will soon be clear. Try it out as shown.
We are now ready to include some targets, a single character in this
case, des ignated by bS. The following add it ional lines will generate up to
35 such random targets, d istr ibuted randomly over the screen.
2 INPUT b$
4 FOR n = 1 TO 35
6 PRINT at 21*RND, 31*RND; bS
8 NEXT n
Now we can RUN the program again and when asked for b$, enter the letter
"o" or "X" for the time being. Move the puck about and it will wipe out
the targets as it passes over them.
In a game program some add it ional action is usually taken when the puck
hits a target. So we'll add another line asking SCREENS to look at the
PRINT POSITION contained in LINE 60 and to take some special action if a
target happens to be there before the puck is printed over the spot.
Again, for the sake of s impl ic ity, the action will be just a BEEP.
70 IF SCREENS (L,C) = BS THEN BEEP .05,25
We can also use SCREENS in a negative sense by rewr it ing I ine 70 to
70 IF SCREENS (L,C) <> "" THEN BEEP .05,25
Now RUN the program and enter any character with the CODE of 33 to 127.
Enter the character, not the CODE number. Move the puck about and we
should get a BEEP each time a character is hit. Try running the program
and entering inverse characters or some graphic ones. They do not work, and
now you know why.
Now we can use anything at all for a target as the field has only targets
and spaces. There is only one drawback. SCREENS does not know the identity
of the targets. It only knows that they are not spaces. In some game
arrangements this is all that needs to be known.
Have you figured out the reason for the PAUSE 0 in line 90? Without it
the GOTO construct ion fills up the PRINT POSITION in line 60 with the puck
itself. SCREENS reads the wrong character and BEEPs. With PAUSE the
program is held up until an arrow key is touched. In this way SCREENS
looks at the print position just before the puck gets to print on it. This
is the essence of this kind of a game program.
Line 70 is usually written in terms of CODE SCREENS (L,C). To be
cons istant with this practice, the code number of the target character
should be used after the = mark instead of it's string counterpart . Either
As we have seen, SCREENS is limited in it's capab i I it ies. But the TS2068
has at least four other methods of character identification that can be
used in these s ituat ions. Some of these are not commonly known but will be
d iscussed in coming issues of QuarTerS.
This article was re-typed from one appear ing in the Summer 1985 issue of
the QuarTerS publ i cat i on. It is the first of a series of articles by Warren
Fricke that we shall be re-publishing. G. Chambers
ZX8 1 RESOURCES — JOYSTICK
Rene Bruneau Noveaber 1992
Several aeetings ago, Jeff Taylor deaoed a Zebra joystick
interface for the 2X81. At that tiie, several people
expressed an interest in taking one, so I looked through ay
files for a circuit that I could use in a construction
article. I found one written up in the June 1984 issue of
Electronics Today International and changed one of the chips
and added the edge connector to lount the interface on the
back of the ZX81. The interface is 1/Q sapped to Port 31,
■aking it compatible with the 2068 to play Spectrua and 2068
prograis that use a Keapston Joystick systei. It will also
work with a Coaaodore 1351 louse in joystick lode.
As with past projects. I have provided a PCB aask to be
photocopied onto TEC 200 lylar fill for transferring to a
blank board. Load the coiponents as shown on the overlay,
being careful to install the sockets and capacitor
correctly. The edge connector is located on the copper side
of the board, with the coiponents and extender on the side
facing away from the coiputer. Check for poor solder joints
and juips between traces and clean any that are suspect.
Before you install the ICs on the board, plug the assembly
onto the rear edge connector of your coaputer, turn it on,
and confiri that the coiputer initializes properly. If it
doesn't, quickly shut off the aachine and check your work
If you have access to a 2068, testing is siiple. Enter the
following prograi and run it with a joystick plugged in.
1 PRINT AT 15,10; IN 31
2 PAUSE 5
3 PRINT AT 15,10;' 1
4 6QT0 1
For the ZX81, a short aachine code prograi Bust be entered
1 REM 123456
2 FOR X=16514 TO 16519
3 INPUT A
4 POKE X,A
5 NEXT X
7 PRINT AT 15,10; USR 16514
8 PRINT AT 15,10;" '
9 60TO 7
The data requested in line 3 is:
219, 31, 6, 0, 79, 201
If the interface is working correctly, a 0 will be printed
in the Middle of the screen. The nuiber should change as you
aove the joystick or press the fire button. The nuaber
printed will correspond with those shown below. Note that
holding the stick in the corners will give you a sum of the
vertical and horizontal values. For exaaple, with the stick
in the top right corner a 9 is printed on the screen,
holding down the fire button at the saae tiae increases the
nuiber by 15 (DOWN + RIGHT + FIRE = 3 + 1 + 16 = 25)
Write code to 12 REM stateient
For those who have a copy of FIGHT SIMULATOR, here are some
pokes to adapt it to allow the use of a joystick. Use a
FOR/NEXT loop to enter the code. He will provide additional
prograa pokes in future issues of this newsletter.
33, 239, 239
33, 239, 223
33, 247, 223
33, 239, 247
205, 187, 2
with 50 Xs.
IN A, 31
JR Z, EXIT
LD HL, 239, 239
LD HL, 223, 239
LD HL, 223, 247
LD HL, 247, 239
CI 4u7 Tantalua Capacitor
R1-R5 IK 1/4 watt Resistor
PI Male 9-pin Subd Socket
P2 ZX81 Edge connector and extender
Misc. 2-14 pin dip, 1-20 pin dip, Solid wire for juapers
/oN A A gj sl J ?1 d
* ii — \w
<i — vw-
(i — m-
ADD. DEC. CODE
17316 205, 247, 75
ST"' * ■
1992 QL Library
New and revised
There are at present 271 programs/utilities in the QL Library, in the following
Disk Title Free Mem Contents
1 OA 0/1 AAD
f-\ tr i r\ ri
r.i hrarv Ca1"a 1 osue
DDD / X'+H-U
A.77 /1 LLC)
iy emu kj
QQ /1 LLC)
77/ if tU
Xv c Via et-i
VJ CtlUC o
1 1 in/1/iAfi
Kcv X o cvJ.
('It* a oVl 1 P <?
Hr>ufar*H T CI^^P file
Pic s 1
->9A / 1 LLC)
P 1 P1"11T%P CI
JL -L l_ Ul c o
Psion related subjects
Sound and music
Founts. Tests. _doc info files.
Small. C. by Tim Swenson
Z88 files in QL format (Untested)
QL Hackers Journal by Tim Swenson
(For advanced QL Programmesrs) Vols 1-9
This is a total of 19 disks of varying interest. Some old, some changed, some
I know that some of those disks could be lumped together, but I feel that this
presentation leaves possibilities for additions without too much trouble.
If you wish to order any of the above, please send FORMATTED disks of your
choice, with return postage.
I can copy to 5 1/4 40 or 80 track or to 3 1/2 DD or HD. Complete disks only.
For the MDV user I will try to copy to your formatted Cartridge if you designate
the particular program by Disk Title and Title of program.
It is almost impossible to fit more than one program onto one cartridge.
I will not be responsible for faulty cartridges or disks, or for the formatting
Hugh H. Howie.
586 Oneida Dr
18 % |? hm
S INC- LINK CONTENTS
prepared by George Chambers
Each entry is prefixed with the year and first month of issue (eg, 8301 =
Jan/Feb 1983, 8303 = Mar/Apr 1983); and with the volume & number (eg, 3/1
= volume 3 number 1 ). These are usually followed by the ( first ) page
number of the entry.
8301 1/1 P. 01 Is your calendar accurate by George Chambers.
8301 1/1 P. 02 Cassette Recorder Interface by George Chambers. Tips on
cooling your ZX81 by Peter Harvey.
8301 1/1 P. 03 The ZX81 as a Character Generator by J.J Cast i llos. Adding
a Joystick to the ZX81 by Stan P iotrowsk i .
8301 1/1 P. 05 Review of Memotech High Resolut ion Graphics Pack by J.J,
Cast i I los. In Praise of ZX Printers by Greg Lloyd.
8302 1/2 P. 02 Review of Mult i FORTH EPROM Chip for the ZX81 by J.J.
Cast i I los.
8302 1/2 P. 03 Book Review "Master ing your Timex Sinclair 1000 Personal
Computer by J.J. Cast i I los. A Short program in FORTH by J.J. Cast i I los.
8302 1/2 P. 04 BUGBYTE ZXTK Appl icat ion notes by George Chambers.
8302 1/2 P. 05 Tape Head alignment by Stan P iotrowsk i .
8302 1/2 P. 06 Understand ing ans using PEEK and POKE by Stan P iotrowsk /•
8302 1/2 P. 10 Adding 2K RAM internally to the ZX81 by Jack Paget.
8303 1/3 P. 01 Mult i pi icat ion accuracy with the ZX81 by George Chambers.
8303 1/3 P. 02 Advanced Machine Code programming by Stan P iotrowsk i .
8303 1/3 P. 06 A modem for the TIMEX 1000 or ZX81 by Franz Hrazdira.
8303 1/3 P. 05 Tips on protect ing your ZX81 program from pirates by J.J
Cast i llos.
8303 1/3 P. 06 Reviews of Hunter boards, Memotech' s Memocalc, MCODER, and
the program EVOLUTION by J.J. Cast i llos.
6401 2/1 P. 01 Messages from the Preident and Editor
8401 2/1 P. 02 Poor mans FASTLOAD by C. Goudeseune. BASIC PROGRAMMING, a
lengthy article by C. Goudeseune.
8401 2/1 P. 09 Lengthy article on Machine Code programming by Stan
P iotrowsk i .
8402 2/2 P. 01 Meeting agenda
8402 2/2 P. 02 Making a joystick for the ZX81 . Including the hardware A
software by George Chambers.
8402 2/2 P. 05 Basic programming by Stan P iotrowsk i( ?) .
8402 2/2 P. 07 Machine Code programming by Stan P iotrowsk i .
8402 2/2 P. 12 Several computer puzzles by George Chambers
8402 2/2 P. 14 TTSUC membership survey.
8403 2/3 P. 01 Hardware hints (cooling the ZX81 ) by Virgil Roman.
8403 2/3 P. 02 Aligning decimal points on the ZX81 by George Chambers
8403 2/3 P. 06 Merging Basic programs by George Chambers. Machine Code
programming article by Stan P iotrowsk i( ? )
8403 2/3 P. 09 Article on adding single-key shifted functions to your
external keyboard using diodes.
8404 2/4 P. 01 Checking computer accuracy by Bill White,
8404 2/4 P. 02 Machine Code program with one POP by K. Van Vie it,
8404 2/4 P. 03 Machine code programming by Stan P iotrowsk i .
8404 2/4 P. 08 BASIC programming article by Stan P iotrowsk i .
8404 21 4 P. 10 Low Memory - SAVE I LOAD program by Bob Croker
8405 2/5 P. 01 BASIC programming article by Stan P iotrowsk i.
8405 21 5 P. 04 Machine Code programming article by Stan P iotrowsk i .
8405 2/5 P. 08 A short program in FORTH ( ZX81 ) by J.J. Castillos
8405 2/5 P. 09 An article on the Z80 reg isters and instruct ions.
8405 2/5 P. 10 Z80 OPCODES table.
8406 2/6 P. 01 Letter from the Editor
8406 2/6 P. 02 Store BASIC on an EPROM with an EPROM programmer by Virgil
8406 2/6 P. 04 SYNCBITS - a list of resources for all T/S computers by Ian
8406 2/6 P. 05 Article on building an 8K EEPROM board by John Roach.
8406 2/6 P. 07 Ideas on includ ing author credits in a Basic program by
8406 2/6 P. 09 TS 2068 programming suggest ions by John Roach.
8406 2/6 P. 10 Machine Code programming by John Roach.
8406 2/6 P. 11 Table of ZX81 Key (board) values
8406 2/6 P. 12 Schematic for 8K EEPROM board by John Roach.
10/3 p. 3 Sine-Link Contents R.Mitchell
10/3 p. 6 Notes from my correspondence G. Chambers
10/3 p. 9 QLIPS Beginners Corner A.Pywell (H. Howie-1
10/3 p. 15 ZX81 Resources 64 K memory R.Bruneau
10/3 p. 17 German QL Users Club B.Harmer
10/3 p. 18 QL Success CP/M Emulator L . Laf err lere
10/3 p. 22 Britain's Spectrum Scene G.Parrish
10/3 p. 24 4Times screen* Abed Kahale
10/3 p. 25 ZX81 Resourves Rem Generator R.Bruneau
10/3 p. 27 ZX81 Magazine A.Baune
10/3 p. 31 A tape index L.Cottrell
10/3 p. 32 Clone vs 2068 S.Gunnhouse
10/3 p. 35 Challenge to programmers D.Lambert
10/3 p. 36 Analog Science K . L . Thompspon
10/3 p. 36 YMLTK L.Laferriere
10/3 p. 37 QLIPS Winde:; H.Howie
10/3 p. 38 ZX81 Tight Security A. Ho
10/3 p. 39 Disk Drive power supply LARKEN H.Miller
10/4 p. 5 Sine-Link Contents R.Mitchell
10/4 p. 11 Superbasic Your Powerful Friend A.Pywell
10/4 p. 15 ZX81 Resources Moving Ramtop R.Bruneau
10/4 p. 15 ZX81 Sound Analysis
10/4 p. 16 IBM Clone and Spectrum . R.Calvin
10/4 p. 17 TEXT87plus4 H.Howie
10/4 p. 19 2068 Second Screen D. Fritz
10/4 p. 21 QL Ramblings Joystick , TEXT87p lus4 , maillist.L. Laf err i ere
10/4 p. 22 Mike's Notebook M.Di Rienzo
10/4 p. 23 ZX81 Newsletter for Sinclair/Time): A.Baune
10/4 p. 27 Reduce number of disks with TK2 . H.Howie
10/4 p.2S QLIPS etc. H.Howie
10/5 p. 3 Editorial ( Interesting ? ) J.Taylor
10/5 p. 3 Spectrum Game " Aliens " 7 J.Taylor
10/5 p. 4 Programming exercise 2068 G.Chambers
10/5 p. 7 Using ALTKEY for " Macros "in QUILL H.J.Ciase
10/5 p. 11 ZX81 Resources R.Bruneau
10/5 p. 13 Larken format to match IBM ? S.Gunnhouse
10/5 p. 17 Visit to NESQLUG H.Howie
10/5 p. 18 TREE_BAS H.Howie
10/5 p. 19 Disks , cassettes , modems, etc. B.Harmer
10/5 p. 20 Battery Operated Bike D.Clery
10/5 p. 21 ZX81
10/5 p. 25 Transferring files from Z-B8 to 2068 J.Shepard
10/5 p. 27 Superdasic Ramblings A.Pywell
10/5 p. 30 QLIPS, Ribbons. H.Howie
10/5 p. 31 2068 on business trips L.Cottrell
10/5 p. 32 Larken Oliger system. G.Chambers
10/5 p . 33 Emulators C.Delhez
10/5 p. 35 Emulators ? 386 to Spectrum. R. Calvin
10/5 p. 37 SINC-LINK Contents R.Mitchell
SINC-LINK listings 9207
issues 10-3 to 10-5 ^07
by L. Laferriere 9;07
ZX SPECTRUM MODIFICATIONS TO U.S.A. STANDARDS
While I was on a business trip to Europe fast December, I purchased a
ZX Spectrum computer. No, I'm not tired of my TS2068, but my first love is
my so I der ing iron and a heap of el ectron ic components with a burning
desire to experiment with these el ectron ic marvels we call computers.
The TS2068 and the ZX Spectrum are closely related in design, however
there are physical and e I ectron ic differences between both computers. Many
European publ icat ions provide a store of add-on do- it-yourse I f hardware
articles to enhance the Spectrum, but NOT The TS2068. My Spectrum will now
become a test bed for building Spectrum hardware, then mod if y ing the
hardware to operate with the TS2068.
This article is ded icated to those individuals who have a Spectrum or
intend to purchase one and want to get the most out of it - to operate on
110 volts without a step-up transformer; convert the PAL decoder to
operate on NTSC video standard for colour operat ion; and add a compos it e
video output for your monitor.
The orinal Spectrum power supply module requires 220 VAC at the
primary, and outputs approximately 9-10 VDC. Two options for the
mod i f i cat i on can be cons idered .
1 - Rewind the original transformer primary winding to operate at 110V AC,
or adding add it ional windings to the secondary to up the output voltage,
using the original primary windings. The transformer design allows fairly
easy rewind ing of the primary or secondary, but it is work,
2 - Remove the original transformer and replace it with a commercial 110
VAC, 18 VAC Centre Tap transformer.
I chose option two because I had an 18 VAC CT transformer on hand that
fit into the Spectrum power supply case. The reason a 18 VAC CT
transformer was selected, is that a 9-10 volt transformer is pretty hard
to come by, and by cutting the transformer centre tap and paralleling both
9 volt windings with proper phasing, the voltage is 9 volts with the
operat ing current doubled. Also the original power supply rect if icat ion
and filter assembly can still be used without mod i f i cat i on.
POWER SUPPLY CONVERSION
Modul a tor
18 Vol t Trans-former Secondar y Leads
Exposed After Opening Insulation Tape
The first step in this operation is to remove the power supply case top
by removing three (3) Philips head screws. Remove the case top and set
aside with the three retaining screws previously removed. Carefully remove
the transformer with the filter assembly and both input and output cables.
Measure the transformer core (metal laminat ions ) for height, width, and
length and record these measurements. I used an old Radio Shack
transformer, however I'm not sure it is still available. A visit to any
el ectronics TV supply house will provide you with the necessary
tranformer. Ask for an 18 Volt Centre Tap, 1 amp filament Transformer, and
measure it so that what you buy will fit the case. Surgery on the
transformer first begins with removal of the mounting frame. Set the
transformer on your work bench upside down and pry up the four (4)
retaining tabs on the bottom of your transformer core. With a common
screwdriver (flat blade), insert the blade between the mounting frame and
the transformer core and apply a prying motion until the frame has exposed
both sides of the transformer core. Remove the frame from the core ana
trial fit the tranformer into the power supply case. If the f,t is a
little loose, a strip of foam tape (weather stripping) will snug things up
at assemDiy rime.
Remove the transformer from the case and locate the secondary side.
This is the side with either two green lugs and one lead with stripes, or
three solder lugs. With a sharp knife (X-ACTO, #11 blade) or razor blade,
using light cutting pressure, cut a slit from top to bottom at the centre
point on the transformer secondary side insul at ion. Carefully pull both
sides of the cut tape towards their respect ive sides which should expose
three copper wires either terminated to lugs or wires.
Using the low wattage soldering iron, desolder the centre tap winding
from a lug or wire. Examine the copper wire tap; it can be either a loop,
or two separate wires. If it is a loop, cut the loop, and if it is two
wires, separate them. Cut two small strips of tape, any kind, and place
one strip on one of the centre tap wires. This is for identification
purposes only, to properly phase both both secondary windings which we
will parallel. Using an ohmmeter or a cont inuity tester, connect one lead
of the test instrument to the CT lead having the strip of tape. The other
test lead is touched to either or both lugs/wires to locate the mating
lead of the CT winding having the tape. Now, follow this careful I y. Place
the other strip of tape on the lug/lead which did NOT indicate continuity.
Connect both taped wire ends together, remove both strips of tape and
solder these leads together. Connect the remaining two leads together and
solder these as you had soldered the others.
Before going further, the transformer output voltage must be tested for
a voltage and correct phasing. Connect a two wire cable with a proper 110
VAC connector to the transformer primary. The primary side should state
110 VAC or have two black wires attached to it. Insulate these connect ions
to avoid any contact with the line voltage. Set your voltmeter function
switch to AC and the range switch to 25-50 VAC. Plug the line cord into an
AC wall outlet and touch both secondary connect ions with the voltmeter
test probes. If the voltmeter is reading 9 VAC or higher then all is well.
On the other hand, if no voltage is present, then remove the line cord
from the wall socket, desolder the secondary connect ions previously made
and switch secondary leads. Repeat all previous steps until proper AC
voltage os obtained.
Attach two 2" leads to the secondary contacts and solder, then place
some insul at ing tape over the exposed secondary leads. Place the
transformer into the bottom of the case and add some foam-backed tape to
it if the fit is too loose.
Desolder the filter assembly circuit board from the original
transformer and place in the case next to the transformer secondary.
Connect both secondary wires to the filter circuit board in the holes
which the original transformer was soldered to. Any wire can connect to
either hole for tranformer connection. If you wish, the AC line strain
relief from the original transformer can be removed and the 110 VAC line
cord can be inserted into it for a custom fit.
Set the function switch on your voltmeter to DC and the range switch to
25 VDC. Plug the line cord into the AC socket and monitor the output
voltage at the power supply connector. A reading of 9 VDC or greater will
NTSC COLOUR OUTPUT
The Spectrum operates on a European video standard called PAL, which
means Phase Alternating Lines. PAL provides 625 TV lines as opposed to 525
TV lines with NTSC. The colour is automat ical I y corrected at trasnm iss ion,
thus eliminating the requirement for a Tint or Hue control. If we operate
the Spectrum without a change in colour burst frequency, then the output
on a TV screen will be black and white, and possibly some diagonal lines.
Fortunate I y a crystal change from U.U3 MHz to 3.57 MHz is all that is
necessary to have the Spectrum perform in colour in the USA.
A trip to your local Radio Shack should solve the crystal requirement.
Ask for part No. 272-1310, COLORBURST CRYSTAL at $1.69. If they do not
have the crystal, any TV or E tectonic Supply outlet will have one. Just
make sure it is a miniature case, HU-18.
Please note there are two (2) crystals in the Spectrum computer. A 14
MHz crystal operates the system clock and should not be removed or
replaced with a crystal of another frequency. The PAL crystal, 4.43 MHz is
the one to replace.
Open the Spectrum case by removing five (5) Philips screws on the case
bottom. Carefully open the keyboard section of the case and locate a
Philips screw approximately centre on the PC board. Remove this screw and
lift out the PC assembly with the keyboard still attached. If you are
careful, you will not have to remove the keyboard case section.
The 4.43 MHz crystal is located next to the TV RF modul ator . Ensure
that you have located the right crystal as the clock crystal shares the
same approximate location. Heat up your soldering iron and grasp the 4. 43
MHz crystal with two fingers. D isconnect the solder ing iron from the AC
line, and quickly heat up one crystal lead and gently pull with a slight
twist at the crystal. Repeat the previous step until the crystal is
removed. Note: the solder ing iron will not zap any semiconductor within
the crystal circuit with a static charge, if disconnected from the AC.
Plug the solder ing iron back into the AC line to build up heat. Insert the
3.57 MHz crystal into the PC board using the same holes as the crystal you
prev ious I y removed. Again, d isconnect the solder ing iron, and quickly
solder both crystal leads to the PC board. Clip oof both leads of the
crystal on the unders ide of the board. Place the PC assembly with the
keyboard into the lower case.
Attach a cable to the modul ator jack and the other end to the UHV leads
on a TV set. The approximate channel should be between 30 and 36. Plug in
the modified power supply and turn on your TV. Rotate your Channel Select
switch until the Sinclair copyright message appears on your TV. If you do
not wish to add a Video Monitor output to your Spectrum at this time, then
d isconnect power and the TV cable, and reassemb I e the computer case.
NOTE: My Spectrum did not have a trimmer capac it or in the crystal
circuit. If yours does and the image on the TV screen appears poor, then
you may want to attempt to adjust the trimmer to peak the picture.
This article appeared in an old issue of the L.I.S.T. newsletter, and
has no credit line. I suspect it may have been written by Nazir Pashtoon.
I have retyped it, since my copy is in poor cond it ion. G. Chambers
from Nite Time News by CATUG
USE LESS RAM BY TYPING MORE
Don Lambert wrote me a letter and
stated that being a less
experienced programmer he could
not understand why I used
statements with VAL and CODE in
The answer, Don, is to save
program space. Just a couple of
bytes saved can sometimes save a
whole disk track of 5090 bytes!
One of my favorite examples is
Larry Kenny opening up channel 4
to access his LKDOS because PRINT
# 4 is easier to type [less key
strokes] than RAND USR 100".
[page 11 of his V3 manual] Also,
$J r^> he told me it takes up less RAM
space in a program. Well, LARRY,
it can USE UP MORE RAM space! The
problem I have is channel 4 is
also assigned to my ZEBRA Talker
and I can't change that.
Consider a short program to load
LogiCall. Get in front of your
machine and do the following:
Turn on your TS2068 and type
PRINT FREE <ENTER> . You get
38652. This is our free RAM
space. Now enter the two lines:
10 RANDOMIZE USE 100: OPEN #4,
20 PRINT #4: LOAD "L.B1"
Now type PRINT FREE <ENTER> . You
get 38600. Strange, 29 keystrokes
used up 52 bytes!
Now EDIT the lines and put VAL
with quotes around the 100 and
the 4s. The program now reads:
10 RANDOMIZE USE VAL"100": OPEN
# VAL" 4", "dd"
20 PRINT # VAL"4": LOAD "L.B1"
Now type PRINT FREE <ENTER> . You
get 38609. Strange, you just
added 9 keystrokes to the program
and gained 9 bytes of RAM!
Now lets try the ultimate RAM
saving trick. Most numbers over
31 can be expressed in the
program as CODE. Let's change
VAL"100" to CODE"d" , do you
follow me, Don? It is on page 242
in the TS2068 manual. The program
10 RANDOMIZE USE CODE"d" : OPEN #
VAL" 4", "dd"
20 PRINT # VAL"4": LOAD "L.B1"
Now type PRINT FREE <ENTER> . You
get 38611. Losing the two zeros
bought us two bytes. Notice that
the following statements all mean
the same thing.
RANDOMIZE USR 100
RANDOMIZE USR VAL "100"
RANDOMIZE USR CODE "d"
But what about OPENing channel 4
to save RAM space. Type in the
10 LET h=CODE "d"
20 RANDOMIZE USR h: LOAD "L.B1"
Now type PRINT FREE <ENTER> . You
Both programs will LOAD LogiCall
but the channel 4 call uses 41
bytes while the USR call uses
only 28. Also, for the record,
RAND USR h is six bytes shorter
than PRINT # 4 and just as easy
SO WHY OPEN CHANNEL 4?
THE FAR SIDE By GARY LARSON
10 bO © 1992 FtrWorta Inc/DmntKrtW Ov Unmu Pro SynttcMi J^m— *
'Well, this isn't very promising.
RT 1, BOX 117
CABOOL, MO -65689
Repair Charges for SINCLAIR/TIMEX Computers Revised July 1, 1992
Prices do not include shipping and handling charges.
Shioping charges will vary depending upon weight, distance, and method.
I will ship via the cheapest method unless you specify otherwise.
The minimum handling charge for shipping is $2.00-
There may also be an extra charge for repairing modified equipment.
The minimum extra charge for modified equipment repair is $5.00.
Definition of modified equipment: Any circuitry changes on the inside of
the equipment case that involved the addition of components, wires,
integrated circuits, or hardware. Customers who send in computer equipment
that has had modifications done to it, which change the manufacturer's
original design are subject to paying extra.
The following items Mill be repaired for $5.00 each + parts & shipping:
TS-1000 ZX-S1 1016 Ram Pack Any MEMOTECH Module ZEBRA TALKER
The following items will be repaired for $10.00 each ± parts & shipping:
TS-1500 TS-2020 TS-2050 PC-8300 ZX-80 Any BYTE-BACK Module
TS-2040 ZX-99 Any BASICARE Module
LARKEN RAMDISK Z-SIQ AERCO 2068 Centronics
The following items will be repaired for $1 5.00 each + parts & shipping:
TS-2068 SPECTRUM A&J MICRODRIVE LARKEN 2068 FDI KEMPSTON FDI
MIRACLE 512K LARKEN 1000 FDI CUMANA FDI
The following items will be repaired for $20.00 each ± parts & shipping:
The following items will be repaired for $25.00 each + parts & shipping:
SINCLAIR QL AERCO 1000 Centronics AERCO 2068 FDI
TRUMP CARD ZEBRA 2068 FDD System AERCO 1000 FDI
For repairing modules, printers, monitors, or other computerized equipment
not listed above - write for a price quote for the items you want repaired
For modifying or upgrading any computer or module - write for a quote.
I also service ATARI. COLECO. COMMODORE. IBM , OSBORNE. TI . and TRS-80.
In house turn around is usually 2 to 4 weeks.
Upgrades and problem cases may take longer.
You will be notified of any unusual delays or excessive repair costs.
Instructions for sending in computer equipment:
1. For repairs, please use a separate sheet of paper to describe in detail
the problem you are encountering, and whether or not the problem is
intermittent. List any software or hardware that are associated with the
problem. Also list any modifications that have been done to your equipment
2. For upgrades, please enclose or specify the magazine article or other
source of information for doing each upgrade.
3. You may include a check or money order as a deposit for repair costs.
You will be notified if a balance is due. Over amounts will be refunded.
4 .. Carefully pack and ship your equipment to the address below via UPS
or parcel post. UPS is sometimes cheaper, especially with heavy items.
RT 1, BOX 117
CABOOL, MO 65689
Phone (417) 469-4571 daily 8:00 AM till 8:00 PM Central time.
If there is no answer, try another time. I'm busy building a log house and
can't always hear the phone. Please do not call after 8:00 PM Central time.
VISA / MASTERCARD accepted with 4% surcharge.
(Charge customers must provide Acct. #, expiration date, and name on card.)
RT 1, BOX 117
CABOOL, MO 65689
Repair Service for America's
Favorite Home Computers
and their accessories
ADAM ATARI COMMODORE
IBM OSBORNE SINCLAIR
TIMEX TI TRS-80
BUY - SELL - TRADE - UPGRADE
Write for prices
Ph. (417) 469 - 4571
8 AM to 8 PM Central time
Would you buy a used Timex-Sinclair computer from these men?
SINC-LINK wants your articles, projects and experience(s) .
Write to us and we'll publish your piece and put your
name in lights, well, bold type anyway.
Looking for something? Got something for sale?
ADVERTISE FREE IN SINC-LINK
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November 22, 1992
Dear Out-of-Town Members,
nu.iTVlnvJ'l*6''6*!1"9 ne"jle*ter, ' see. Jeff says, ' t here ' s only 28 pages this month'.
ONLY. ONLY? Seems to me that's quite enough, especially when I look at the contents.
Actually, we can only send out 36 pages before we have to pay more for postage; we
exceed the 100 grams marker, whereupon we have to pay $1.30. To the USA, and other foriegn
countries, that ts. So it behooves us to stay within that limit.
because we do
appear in our
We don t publish much about our club meetings in the newsletter. Probably
not have a member to take on that task. Maybe also, our meetings are not of
interest. But this month we have some items to mention to you. They should a
next news letter .
nn» illViYnt0Ur Jnll°Wll "*mb.er.shiP is filing we have revised one of our club bylaws, the
one pertaining to the definition of a meeting quorum. We were afraid we might not be able
to function, some time in the future without this change.
off%%\™us7ndesl°.read "** '° percent of tne membership must be present to conduct
^s;/^;^?:^^" consist of a minimum or rive members' three °r *hom te
The change was approved by a membership vote, with a meeting quorum of 11 members.
,nJie:+alS°rhaVt Z*dJ>ZoblemSt wit,n our Pres*n* meeting place, Forest Hill Collegiate
^SSlViS/Mr ttr00^' Difficult/ 'J! Peking, hard-to-find meeting rows, missing
^fhroom facilities, etc. So we are going to meet at my home from now on, 1U Richome
Court. "ell we also do have a QL interest group who are going to meet at Hugh Howie's
home, on a different Wednesday of each month. 9
What this means is that our group has shrunk in size to the point where it is feasible
to meet in someone's home. But still strong in enthusiasm. feasible
with S^Stir^^riC^^J^'r^/^'r!^"/^* a year ago 1 suPPl''ea a Toronto museum
JJ^Su ,/ f .y father had knitted while he was a prisoner-of-war durina the 1st
World war. It was knitted with needles made from fence wire, and with wool unravel 1 ed from
ineit°PST°he ZTlZT* ^7 *°CkS- If *-aS- °, S°rt 0f Saa">ler * 9'eat variety of patterns
The show is on now "Vnd Y'"* a,\exhi.bit l°n °f textiles having a human interest to them.
The show is on now, and I was interviewed on a CBC radio station in connection with it.
}^1L0fr0ii.r °lUb members> *en Gamey, took me to task gently, for not respondino to his
i:^r%i,2r^es^/e%2:x and 1 hope he is !n th* °f -^r^w:
He had a point though.
refind 171"°° '* ' "** *"m f° responding to your letters, drop a line and
MscriTfiTeT ThJdnl nnrZ;r°1tine thQ.f WQ.S P^Pored by Bob Mitchell, used to sort
Mscript files I had a particular application for it. What it was, was this-
oo as, for It. ,t a,so So.'"£'Zl? S 'ulrVr'y TuL'er.'"*0 ^ ""^ ""^
Another thing. In the July/August OOT letter I mentioned that I had several disks
designed to allow the Spectrum to be emulated on a 386-PC machine. One of our members hat
made a copy of the disks, so if anyone is interested in trying them out, I can loan you a
W copy. Another suite of disks for the club I ibrary! I Ask for Spectrum Emulator disks. You
will need a 386- or later type PC machine to be able to make use of themTlfaTbls^someone
can try it out and give us a review article for the newsletter. Think of it; your name in
our newsletter! J
I prepared an index for the early issues of the S1NC-LINK to round out the index
prepared by Bob Mitchell. It is in this issue of the newsletter. I am placing the indexes
for the years 1983 to 1992 on a disk for the club Larken library. St i 11 another as yet
un-numbered disk for the library! a* yGX
2068erLn^aU ,hQS ,?P ? buffer circuit 5° that I can use a remote keyboard on my
TFLZtZP% i '+i-WOU,id likeJ° USe the k°yboord separated from the 2068 by a ribbon cable
nn+ ZZZZ 5 feet'n \ength. To do so we need to have a buffer circuit, otherwise it will
£^ £W ^^T^^a SE'fc ThTpTr^d
3Si: Ve^iyTrZ ziTs^. i W
resign as President of the club, but we declined to accept it! ottered to
I have been corresponding with Bill Pederson, recently. You may remember I mentionr
. m ■» ----- — . . . - ~ ~ ^ . ^ , • f i k^cih ijr, ' wiu ihu y i amain ut
that in my last missive. He has written a letter, which I am going to ask for parmiss,
Vr\/JPrL , "! °Ur newslettef' Jt contains some interesting tips and observations about the
ant pc *J~nZ f ' Possibly in the next newsletter. Bill also send a set of schematics
™ 7L Z layoutJ Pertaining to an external ROM and EXROM for the 2068. Idea being tha
POM andiFy^ntreXternai St?.ie Chips and experiment with modifying the code in the
%^hZ EXROM'To y°ur dart's desire, with no need to burn EPROMS, and all that problem
Sounds very interesting. I turned this info over to Rene Bruneau. Hope Problem,
he will nibble. Anyone else interested?
olS^C^nV'ltYK °7X ZllnrZr ' *a¥* inherit°d mother batch of them, including
in I'll sTn7lnn' ,i*+ •* C0MPUTING> and ™me misc magazines that have programs to type
Punk Everlthina Vi * Y°U interested. ^Iso some books, and a bunch of other
^O^r^^r'^^r/n^rX^r^ AerC° interfQCe t0ardS' A°y°°* tested in a
I seem to have run out of conversat ion.