I/O BOARD

1050 Belts

Here at Cottonwood Computers, we would like to offer assistance to the I/O writer in the February/March 1990 issue who was looking for drive belts for an Atari 1050. We have a few 1050 drive belts in stock, at $5 apiece. We can be reached from 9 am to 5 pm Pacific Time, Mondays through Fridays, at the address below.

Stacey Ristagno
Cottonwood Computers
P.O. Box 818
Cottonwood, CA 96002
(916) 347-0416

Another helpful reader called to say that he'd managed to get a replacement belt from Computerland -- the belt was actually designed for an older IBM drive but has worked fine with the 1050 since. Also, Best Electronics carries many parts forAtari products, including belts for those older drives. Infact, according to Best, they carry belts for two different versions of the 1050 drive, the Tandon ($4.50) and World Storage ($6.75) drives. Best Electronics is at 2021 The Alameda, Suite 290, San Jose, CA 95126. (408)243-6950.-- ANTIC ED

Sound Advice

It's a shame that you've gone bimonthly, but the December/January disk showed you still have good programs. Naval Battle was excellently programmed -- and a lot of fun. Your Sound Creator is excellent -- so how about telling us how to use it in our own programs, or having someone send in a synthesizer?

Also, there are a few errors in Sound Creator which are very annoying. If you make a mistake when typing the filename while loading or saving, you will get an error message. Worse, you can't save your waveform, and have to reboot to load a new one. To correct this, you need to add CLOSE #2 to lines 5900 and 6900, as follows:

5900 PRINT "Error in Save" :FOR I=1 TO 100 :NEXT I :TRAP 40000 :CLOSE #2:GOTO 1020
6900 PRINT "Error in Load" :FOR I=1 TO 100 :NEXT I :TRAP 40000 :CLOSE #2:GOTO 1020

If the file is too short (say you accidentally press [RETURN] or something) the program will crash. To prevent this, just add a TRAP 1020 at lines 5001 and 6001.

Michael Shawstad
Moorhead, MN

Epson Not Required

The Antic Numerologist in your December 1989/January 1990 issue does not require an Epson compatible printer for hard copies. It works rather well on a direct connect Atari 1020 printer/plotter -- it as many as four colors. It also works on a direct-connect Okimate 10 printer which simulates the Atari 1025 printer. And, by deleting some of the ? #1 statements in the program (without changing any line numbers), you can also print in 80 columns.

Michael Pascarelli
Port Richey, FL 34668

First Factorials

When my daughter asked me a question about factorials, I thought I'd try to get the computer to do them in BASIC. You see, I'm not very proficient at programming -- I like to putter around in BASIC, but I'm not likely to ever do more than write some simple spaghetti code. But, after some frustration, I did get the loop right and can produce a factorial.

A factorial is a number times one less than itself times two less ... times one. For example, five factorial (written 5!) is 5*4*3*2*1 = 120. My code goes like this:

5 DIM A$(1)
10 ? "Pick a positive integer."
20 INPUT P
30 A=0:C=1
40 FOR I=1 to P
50 A=A+1
60 C=C+A
70 NEXT I
80 ? P;" Factorial is ";C
90 ? "Want another? (Y/N)"
100 INPUT A$
110 IF A$="Y" THEN GOTO 10: END

The highest number you can enter before the answer starts coming out in scientific notation is 13!, or 6,227,020,800. Above 68!, the result will be an ERROR 11 Numeric Overflow message. If you wanted to get fancy, of course, you could add some error trapping, and maybe use the routine in a more involved program.

Perhaps this is old stuff, too easy for a lot of programmers, but I'd never seen it before and was proud to have come up with it. At least I enjoyed myself this evening.

Richard Williams
Pullman, WA

WEFAX Kudos

I have just completed the WEFAX decoder project that you published in the September, 1986 issue and I want to say that it works very well. I enjoy using it tremendously. The maps that I receive are very clear and I find them fascinating.

For the benefit of your new readers, WEFAX are facsimile transmissions on shortwave radio frequencies of weather maps and information (among other things). Next, I am going to search for an RTTY or Baudot decoder so I can decode some of the text that is also available on shortwave.

Eric Anderson
Dover, DE

For other readers who may still want to try this fascinating project, be aware that one essential part-- the XR2211 chip-- is no longer available from Radio Shack. Other sources that should carry the chip include: JDR Microdevices, 1224 S. Bascom Avenue, Sanjose, CA 95128. (800) 538-5000, (800)6626279 in California. Jameco, 1355 Shorauay Road, Belmont, CA 94002. (415) 5928097. Radar Electric, 168 Western Avenue W., Seattle, WA 94086.

Antic welcomes your feedback, but we regret that the large volume of mail makes it impossible for the Editors to reply to everyone. Although we do respond to as much reader correspondence as time permits, our highest priority must be to publish I/O answers to questions that are meaningful to a substantial number of readers.

Send Letters to: Antic I/O Board, 544 Second Street, San Francisco, CA 94107.