SYNCWARE NEWS welcomes correspondence from its readers. Some editing of letters may be necessary for brevity or to enhance clarity.
Computerfest Update
INDIANAPOLIS, IN- Frank Davis, Producer of the Midwest T/S Computer Fest, announced that plans have been finalized for the 1987 edition of that successful event.
The 2nd Annual Midwest T/S Computer Fest will be held May 2-3, 1987 at the Holiday Inn North, 3850 DePauw Blvd., Indianapolis, IN 46268. Hotel reservations may be made by calling the Holiday Inn North directly at (317)872-9790 or through the Holiday Inn Toll Free Reservation Number, 1-800-HOLIDAY. If you mention that you are attending the Computer Fest, the Holiday Inn is offering a reduced commercial rate of $52.00 a night, unlimited occupancy. This hotel is a Holiday Inn Holidome, which offers plenty of activities and excellent facilities for not only those attending the Fest, but their family members as well.
Registration info for the Computer Fest can be obtained by writing to Mr. Frank Davis, [address omitted] Peru, IN. Please mark all correspondence FEST INFO and include a self-addressed, stamped business envelope. Please DO NOT phone. Admission to this year’s Fest will be $4/person, $7/family if pre-registered before March 30, 1987. Admission at the door will be $6/person, $9/family. Indiviuals and families may pre-register by writing to Mr. Davis at the above address.
The 1987 Committee has done a super job planning activities for everyone at this year’s Fest. Beginning Friday night, a banquet will be held for the Vendors, participating User Group Officers, Speakers, and Committee members. This will be a social gathering with spouses encouraged to attend. The cost for the banquet is tentatively $12 per person. Space is limited to 125 people. Advance reservations will be required for this event.
The Fest will run from 9am-6pm Saturday and 9am-5pm Sunday. Planned are a larger Vendor area, two concurrent program tracks with the most popular programs being repeated so all will have a chance to participate, and a seperate area for a Timex Flea Market and Computer Swap.
Space in the Vendor area is being made available at three levels. Tables for retail vendors will be $50/table in advance, $65/table at the door. User groups may obtain a table in the vendor area for $10/table in advance, $15/table at the door. A new category this year will be Cottage Industry. This would be for the individual who has written a few programs and wishes to offer them for sale. These tables will be $20/half table in advance, $25/half table at the door. Space in the Flea Market/Computer Swap area will be free. It is limited to individuals selling used equipment and distributing public-domain software. Copying of programs other than public-domain software will result in the guilty parties being asked to leave. This rule will be strictly enforced throughout the Fest.
This year’s Fest is shaping up to be THE grand event of 1987 in the T/S Community. People from both coasts and everywhere in between will be there. Don’t miss out on the fun and the chance to meet and talk with the Vendors and other “famous” Timex- Sinclair personalities. Get those registrations in now!
The Fame & the Glory
The new SyncWare News programmers contest is rapidly coming to a close. All entries must be postmarked no later than March 15, 1987 to be eligible for the Educational Software Contest (see display ad inside for rules and details). To help you along with your own programs, our own Fred Nachbaur has consented to publish one of his educational programs. Part one of the two part “ABC/123” children’s educational program appears this issue. This should whet your appetite and give you some ideas to get you going on your own programs for the big contest.
Big prizes await the winners, plus FAME and GLORY for all those who enter. Remember, you can’t win if you don’t enter. Get to it Programmers!
Who Is Orrin McGill?
Dear Editor,
Editor; that is a large job. I wish you luck in your new position. I will be monitoring your editorial style with curiosity.
To date, SWN does not offer bio’s, addresses, etc. on the various contributors to the ZX81 saga. Yet one guy seems to have slipped by in the night. Who is Orrin McGill? He is marketing a product called ‘PICTASCAN’, what is it? There’s also another product called ‘MMRY-REZ 64K’, what does it compare to?
We all know about Oliger, Nachbaur, and Kingsley. Are there any other ZX81 wizards out there? If so, they could probably use a little of the limelight too.
Carl Jones, Jr.
Medford, MA
Dear Carl, Thank you for your letter and good wishes. This is the kind of job that at times requires all the encouragement the readers can send my way. We’ll try to keep up the fine standards established by my predecessors.
Orin McGill is a Minnesotan who contracts to the E. Arthur Brown Co. as an independent software and hardware designer. He can be reached through his company, MIN-NY, at (612) 566-7094. The two products you mention in your letter are ones he developed.
MMRY-REZ 64K, alias ZXGR, is a 64K RAM and hi-res graphics pak for the ZX81. It will allow you to develope and store in memory up to five pages (screens) of hi-res graphics, design up to 256 sprites (or attributes), and includes software to allow an ‘Etch-A-Sketch’ funtion as well as program commands like ‘circle’, ‘line’, etc. This product is available through Mr. McGill or E. A. Brown for about $99.00.
PICTASCAN, E. A. Brown, $149.95, is a scanning device that connects to the printhead of an Epson FX-80, FX-85, or compatible printer. By using the printhead to scan back and forth, and the printer carriage to move the sheet through the printer, PICTASCAN will copy the graphics on a sheet of paper to the computer screen. It works in a fashion similar to ‘Thunderscan’ for the Mac computers. Currently, PICTASCAN is available for the IBM and compatible computers. Mr. McGill states that if there is enough demand, consideration will be given to a Timex version.
We appreciate your suggestion regarding giving more information about our contributors. Recently, because of some problems that occurred, it has been the policy of SWN to not publish an author’s address or telephone number unless he or she requested us to do so. However, you’re correct in stating that these folks deserve some of the limelight. As Editor, I’m going to commit myself (and probably be committed for doing so)to do two things for our readership. 1) Whenever possible, we will publish a short bio about the author, telling you a bit about their background and their system. 2) If you desire to contact a SWN author, you may do so through the Editorial Offices here in Ohio. Here’s how. Send your letter to the author to me. Include an envelope with your return address and enough postage to mail your letter first class. I will forward your letter to the author. The author may then contact you if he/she so desires. We’ll try this for a while to see how it works out. -jm
External Power
Dear Editor,
In SWN 4:1, Barry Carter wrote that he was having problems with the video display when he had both his Zebra disk interface and a printer interface connected to his computer (a 2068). I had this problem with my Aerco disk interface and all I had hooked to the computer at the time was the disk interface. Your reply about the problem being the power supply was 100% correct.
As you probably know, when Timex built the 2068 they cut many corners so they could keep the cost down (and the profit up). One of the corners they cut was in the power supply. The power supply is just barely adequate to run the computer. Adding anything such as a disk interface that draws its power from the computer will start to overtax the power supply. In my case, the display was quite readable until the drives were actually accessed. Then the 12 volt supply buss dropped down to 10.5 volts. This low voltage condition was more than the modulator chip could tolerate. Its operation became erratic and I got a ghost image on my composite monitor. Even with a RGB monitor, the display would jitter a bit every time the drives were used. Fortunately, I was able to rid my system of display problems by not powering the add-ons with the computer. I now supply the add-ons power via an external power supply.
To use a separate power supply, the first add-on plugged into the computer should have the 5 & 15 volt buss lines cut at the connector. The external supply should be wired in at this point on the add-on side of the cut. Connect the external power supply +5 volt lead to the trace that went to connector trace 4B, the +15 volt lead to the trace that went to 3B, and the GND or COM lead to 7B and 8B.
One point of warning is in order if you have wired in an external power supply to power your add-ons. The computer supply and the external supply should be plugged into the same power strip. This power strip should have an on/off switch so the computer and the external power supply can be turned on and off together. If you turn off the computer and not the external power supply, you could cause the add-on to operate. This could, say in the case of a disk drive, allow the disk drive to turn on and then operate in the write mode. Any data on the disk could be destroyed, even if the disk had been write protected. So remember, always have your system set up so that you turn the computer and external power supply on or off at the same time.
For those who would like to add an external power supply, there are several companies that sell power supplies that would be good for this purpose. One is B. G. Micro of Dallas, Texas. Check the ads in magazines like THE COMPUTER SHOPPER for others.
David Lockin
Los Angeles, CA
A Monitor Is…
Dear Editor,
I have a few questions regarding color monitors that I hope you can answer.
1) Is an RGB color monitor the same thing as a Hi-Resolution color monitor?
2) A lot of the monitors I’ve seen advertised mention Horizontal and Vertical resolution (ie., so many dots horizontally, so many vertically). What does this mean?
3) Can any or all color monitors be used with the TS2068 in its expanded 64 column mode or does the monitor have to be capable of handling 64 columns?
I am going to purchase a color monitor for my TS2068. I am hoping that your response will help me.
Dennis Silvestri
New Haven, Conn.
Dear Dennis, Your simple questions regarding monitors require very long and detailed answers. So long in fact, Fred Nachbaur, our technical editor, is currently writing an article comparing TV’s, composite monitors, and RGB monitors and describing what to look for as far as resolution, etc. The article will hopefully be ready for printing in the very near future.
Here are a few rules of thumb for you concerning monitors until Fred’s definitive article makes its debut. Unless you have added a circuit that you KNOW will drive a RGB or TTL input monitor, DO NOT BUY ONE! Unless you have modified a ZX81 or TS1000, it will not work with a composite monitor. The TS2068 will work with either a TV or composite monitor. Most monitors manufactured today have a screen which is designed to handle a display 80 columns wide, 24-25 lines long. Such a composite monitor will be more than adequate to display the TS2068’s 64 column wide expanded mode screen.
You might want to check out a few back issues of RADIO-ELECTRONICS and COMPUTERS & ELECTRONICS. They both have run articles on monitors (COMPUTERS & ELECTRONICS is no longer being published). The December 1984 issue of COMPUTERS & ELECTRONICS has several good articles on monitors.-jm
ZX81 Flight Trainer
Dear Editor,
I am an avid subscriber to SyncWare News. As one who has not given up on the Timex Computers, I have come up with an interesting application for a ZX81 computer. I would like to interface a ZX81 to a Pacer MK II Flight Procedures Trainer. The ZX81, its associated software, and an A to D converter would be used to display the horizon, show the runway upon approach, etc., based on the analog outputs of the trainer.
If you or any of your readers have ever performed such a task with this trainer or a similar unit, I would greatly appreciate hearing from you.
Carl Rink
[address omitted]
Sunnyvale, CA
Dear Carl, What a fascinating application! My background is in industrial controls and real-time interface applications. Unfortunately, the work with SWN leaves me little time for outside projects. However I can recommend a book that might give you some insight into getting your litte project to work. TIMEX/SINCLAIR INTERFACING by J. Downey and D. Rindsberg, and published by Prentice-Hall (c) 1983, has a wealth of information between its covers. I am also printing your address along with your letter in case any of our readers can help.
When you do get this project up and running, I’m sure that the rest of us would be more than interested to see how you accomplished the task. Your experiences is this hands on ‘class room’ will make excellent reading. Keep us informed of your progress.-jm
What’s a MIDI?
Dear Editor,
I saw the article on the new Spectrum 128 in SWN 4:1. One of the machine’s features was an onboard MIDI interface.
Since the MIDI first hit the market, I’ve searched for one that would connect to either my TS1000 or TS2068. Needless to say, I haven’t had much luck. Presently, I see my options as to either purchase one and attempt a modification or to build one from scratch.
My question: What comprises the circuitry of the MIDI? Is it typical of other I/O devices or does it have specific differnces? Most MIDI’s I’ve seen advertised are designed for the Apple, Commodore, or IBM. Is the Z80 capable of supporting this device or is it too antiquated?
Thank you for your assistance and all the support your fine publication has provided.
Daniel Wade
Oxon Hill, PA
Dear Daniel, There is no reason to re-invent the wheel or the MIDI in this case. The Z80 microprocessor is more than capable of handling just about anything you’d care to throw at it. Its only limitation is usually the programmer’s ability. Our technical editor, Fred Nachbaur, informs us that the heart of a MIDI device is simply a D to A converter, and the way to a MIDI’s heart is through its serial port. If you have provisions for a serial output port on your computer and obtain a MIDI with a serial input port, you should be able to make the hardware hookup. The software to drive the MIDI is going to be up to you, as there is not any commerical Timex/MIDI software on the market. Tim Woods, TIME DESIGNS Magazine, 29722 Hult Road, Colton, OR 97017, has, at different times, solicited for interested MIDI users to contact him. Perhaps he can offer some advice.
If you do come up with something interesting, drop us a line and let us know.-jm
We’re only Human Dept.
Dear Editor,
By now, probably 1,066 readers have written to tell you of the error on page 4 of SWN 4:1. Tom Bent must have been thinking of a more powerful computer when he said to…
LET YES$="SI"As far as I know, the 2068 will accept only 26 simple, single-letter labels.
Basil Wentworth
Bloomington, IN
Dear Basil, Yes, we have received about 1,066 letters on this one. Here’s letter number 1067.-jm
Dear Editor,
This is in response to the letter in SWN 4:1 from Sergio Frost of San Diego, CA.
A program that lends itself well to the task of computer translator is PRO/FILE by Tom Woods. This simple but fast file program is like a computer index card box. All you need to do is to add files like this:
YES=SIThis file would be found when searching for either Yes or Si. More complex files could be done as well. This application is mentioned in the manual that comes with the program. If you don’t already have PRO/FILE, you should get it for all your filing needs.
Bret Lanius
Decatur, GA
Dear Bret, Thank you for your letter and recommendation for the PRO/FILE program. It would indeed fit the bill as a translator program. -jm
Move Over NASA!
Dear Editor,
I thought you and your readers might like to hear about an interesting TS computer application.
I’ve occasionally been asked what useful purpose my computer has; over and above what could be done without it. I used to kid, “Why I can catalog its software and hardware.” Sometimes I’d be boringly practical, like “I use it for word processing, keeping track of finances or taxes, etc.”. Well I finally dropped the mouth open of the last would be heckler. “I’ve used it to win several contests. In fact, I did so well I was accused of cheating.”
One of my other hobbies is building and flying model rockets. I used a modified simulation program to predict flights to optimize the performance. In one contest I was twice as good as second place, hence the cheating accusation. I was accused of not using the computer (which everyone knew), but of using a rocket engine of a more powerful content than my entry class allowed. Fortunately, all rockets were pre-inspected and my honor remained untarnished. I actually took the unfounded accusation as a compliment; my efforts to do better worked! After several wins, the club members are now interested in learning how to use the computer to improve their flights. I plan to conduct a seminar at a coming club meeting.
To further the use of the computer in this area, I plan to develope a transportable 115Vac/12Vdc system complete with printer for next season’s flights. I will have a 4-1/2″ dc monitor, CAI stringy floppy, and a TTX 6 volt printer all mounted into a home made plywood case. I have visions of a real neat package capable of use in my car or motel room when I travel.
Mort Binstock
Pittsburg, PA
Dear Mort, Congratulations for once again dispelling the myth that our computers are ‘toys’. It would also seem that you have been sucessful in merging two hi-tech technologies for hobbists. If sometime in the future you would care to publish your rocket programs, we would be more than happy to print them in this magazine.-jm