Atari Tree

I've figured out a way to send you all-a Christmas card, and get ANTIC to pay for the postage. It's a BASIC program, which will serve as a kind of singing telegram. After you type it in and run it, you will see how to customize it for your own use.

The program demonstrates multicolor graphics as it displays a Christmas tree complete with colorful ornaments. It will play Jingle Bells in fourpart harmony, display the Iyrics, and change the color of the ornaments at the same time, using only Atari BASIC.

There are no USR instructions and no interrupt-driven machine language routines. Sound impossible? I think it's pretty good myself.

When you enter this program, be sure to enter line 20 first. It is important that the string variable PM$ be defined before anything else.

You can experiment with the program by changing the "player" ornaments, but you will have to erase the old ones first. You can do this in direct (immediate) mode by entering the following as a continuous logical line:

PMADR = (PM$):FOR ERASE = 0 TO 1023:POKE PM+ERASE,0:NEXT ERASE

Your ATARI computer has extensive sound capability. Music and an incredible range of sound effects are available even in BASIC. Those of you interested in learning more about writing computer music and using sound effects, may refer to the many articles and products featured in ANTIC #4.

Listing: ATARTREE.BAS Download