I/O BOARD
BRILLIANT MISTAKE
In my article on Atari Brain transplants (Antic, November 1988) I offered to send a copy of the Public Domain 800 Upgrade by David Byrd to anyone who sent me a self-addressed, stamped envelope.
Unfortunately, there was an error in the initial mailing. A reader, Elmo Ferguson, pointed out the error. I have since sent corrections to all the readers who requested information, and all future mailings will be correct. I apologize for any inconvenience to the readers. Incidentally, I mailed out over 80 copies of the upgrade during 1988.
Lee Brilliant, M.D.
Granada Hills, CA
Readers interested in this upgrade should send a self-addressed, stamped envelope to Dr: Brilliant c/o Antic Magazine, 544 Second Street, San Francisco, CA 94107.--ANTIC ED
VARIABLE SPEED
Lately I notice that quite a few BASIC programmers replace commonly used constants with variables (C1, C2, etc.) claiming that it increases execution speed. This is incorrect. Such a practice can save substantial amounts of memory in large programs, but actually causes them to run slightly slower. A simple timing loop will verify this. I just wanted to set the record straight--keep those 8-bit programs coming!
James Hague
Richardson, TX
Antic Technical Editor Charles Jackson checked this out. He wrote a simple BASIC program that performed many mathematical computations. One version used variables. The second version used constants and ran about 0.12 percent faster. Another problem with using variables is that they can make a program very hard to follow, unless descriptive variable names are used.--ANTIC ED
FLOPPED FLOPPIES?
I think I have several bad disks. Could you publish a disk checker or tell me where I could buy one! The disks in question are all 3M DS, DD, RH soft sector, and the box says "for use with standard IBM PC/XT." Are these the correct disks for my system?
Mel Walker
Philadelphia, PA
The Antic Arcade Catalog carries two programs that can help. If you have an Atari 1050 drive, try Sherlock 1050 (APO 155, $19). Otherwise, use Disk Scanner (APO 145 $15.95)
Basically, any 5 1/4 inch floppy disk should work with your system, but you must format the disk, first. Boot with a disk that has DOS on it, and type [DOS] to go to the DOS menu. (Any Antic Monthly Disk has DOS on it. Simply choose selection 1 from the main menu.)
Be sure to remove your DOS disk before formatting, and insert the disk to be formatted. Formatting will permanently destroy all the data already on the disk so be careful! Type [I] to format the disk and follow the prompts. It's also a good idea to Write DOS files to Disk after formatting (option H). If you don't get any error messages in the process, your disks should be OK.
FAILING MEMORY?
My 800XL seems to be suffering loss memory. The Memory Test shows that I have 8K of RAM missing. I don't think I can RUN or even LOAD software requiring 48K. Is there a way to recover that lost RAM, or does my computer need servicing?
Gregory Pogonowski
Rancho Santa
Margarita, CA
No, your 800XL is fine. Your XL's built-in BASIC is using that 8K of memory. The next time you use the computer, try this: First, unplug your disk drives from the computer (DOS takes up a certain amount of space, too). Next, hold down the [OPTION] key (this disables BASIC) and turn on your Atari. Run the Memory Test again and watch that 8K reappear!
As you might guess, many commercial programs should be booted with [OPTION] held down, to free that memory and disable BASIC for programs that don't need it.
'STEREO" AMP
The Antic Music Processor (December 1988 Super Disk Bonus) is truly one of the most addictive computer programs I have worked with.
To hear my songs with a little more fidelity, I used a coaxial cable to attach my Atari 800XL to my stereo-equipped VCR. The audio signal from my VCR goes to my stereo amplifier. The result was a very satisfying psuedo-stereo sound and I was able to make cassette recordings of the songs directly from my tape deck.
Now, my only wish is for a way to play a "Musical Revue" of all the song files on a disk.
David Waken
Poway, CA
It would be great to have a way to play all the songs on a disk, or even to loop songs to play over and over. We'll add this to the list of good ideas we're passing on to Steven Lashower, the program's author.--ANTIC ED
Antic welcomes your feeaback 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 priorty 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