Star Worms: The Motion Picture


History of Star Worms


Installation instructions



Overview of the game


The player pilots worms through a colorful star field laced with dangerous black holes.


The opening screen


Player enters a number of black holes (1 to 100, or more) and presses return. 


More black holes, greater difficulty.


The initial game screen

There is an 18 x 22 grid of stars and black holes.  The black holes are randomly placed in the grid.  The worm crouches at the bottom right, ready to pounce on the nearest star.  Player uses the joystick (or joystick emulator, such as the number pad) to guide the worm.  Player gets points for each star eaten.  If the worm touches a black hole, it is sucked in, and player loses 1000 points, but gets another worm.


The worm leaves a trail of little x’s as it courses through the stars.  It is rumored that these are droppings, but that is unverified.


Accumulated points displayed in the top left corner.


When a worm goes into a black hole, the universe goes crazy.  Player must press F1 quickly for a new worm, or the game will be over.


I can’t remember how many worms a player gets, but I think there are as many as needed to eat all the stars.  Then I think more stars appear.  I think the game goes forever, or until the player gets tired of it, or forgets to press F1 and the game ends.  If I were writing it now, I’d probably call it “Lost.”


When the game finally ends, the reward is a bunch of numbers and a chance to play again.



The History of Star Worms


Sometime around 1982, I was cleaning a glass coffee maker and I dropped it on the tile counter top.  Instinctively trying to catch it, I lacerated my left hand so badly that I needed plastic surgery in the emergency room to put it back together.  Then I had a week to spend at home, with my hand held up in the air (because Dr. Simon said so).  I decided to spend the time learning about our VIC-20 computer. 


The name of the game came to me first.  I’m sure the worms part came from reading Dune, and Star Wars was big at that time.  I liked “Star Worms” so much that I had to do something with it.  The name has since been used for a bad movie and other games.  I claim that I was the first to use it.


The game was pretty much dictated by my programming limitations.  I had done some Fortran and Basic programming, but never any graphics or machine language.  Actually, this game has no graphics.  Everything is done by changing the characters in an 18 x 22 grid.  I designed new characters for the head and body of the worm so the worm could go in any direction without changing the head.  That’s as close as I got to graphics.


I wrote the game in a week with my right hand (I am left handed) while keeping my left hand over my head.  Some time was spent learning VIC-20’s version of Basic and trying to squeeze the program into the its tiny memory.  If you look at the puny listing, you will be surprised that I had to worry about the size of the program.


I persuaded the kids to play it a few times.  Actually, I think it was their third or fourth favorite video game.  I don’t know exactly because I can’t remember if we had two, or three, other games.


We sold the VIC-20 at a garage sale, but I kept the Star Worms tape.  A couple of decades later, I heard that there were VIC-20 emulators, but I didn’t have a listing of the program and I couldn’t figure out how to get it off the tape.  Then, in April 2006, I ran across the tape and decided to take a stab at it.  The breakthrough came when I learned about programs that would convert a sound file made from a tape into a file that could be run on an emulator.  After some experimentation and tweaking, I got it running.


The kids are grown up, so I can’t make them play the game.  It might be a good game for small kids.  Tell them that it doesn’t hurt the worms when they get sucked into a black hole.  They just go into an alternate universe where there are no giant birds.  And it doesn’t matter if they eat the stars; there are billions, and we are making more all the time.  But little kids these days have better things to do.


So, this is just a family heirloom, like those locks of hair from the kids’ first haircuts that are in the back of some drawer.  Thanks to the people who have written this great software that gets a modern computer to behave like a 1khz machine with 5k RAM, it will be preserved for future generations to marvel over how impoverished we were in the early days of personal computing.



Installation instructions


If you have an interest in the VIC-20, or the game, for some reason (maybe you have played every other game and this is the only one left), here is what you need to get it running.


1.    You need a VIC-20 emulator.  I used VICE.  It’s free, and an impressive piece of software.

2.    The game program is on StarWorms.tap. (Right click the link and then click "Save link as..." or "Save target as...")

3.    Start the emulator (xvic.exe if you are using VICE).

4.    Make sure that Memory, under Settings/VIC settings… is set to “no expansion memory.”  If you get an “OUT OF MEMORY” message from the emulator, you have too much memory in your virtual VIC.  Go figure.  It took me a while to puzzle that one out.  My original VIC had no extra memory, and the program addresses specific locations, so the virtual VIC has to match it.

5.    Click File/Autostart disk/tape image…

6.    Select the StarWorms.tap file.

7.    Click the Attach button.

8.    Wait a couple of minutes (remember, we are back in 1982) until the opening Star Worms screen appears.

9.    The number pad is used to emulate the joy stick.  The numbers 1-9 direct the worm and 0 stops it.




Links and thanks


I posted a message to comp.sys.cbm and got very helpful replies from David Murray and Anders Carlsson.


I used Tape64 (ftp://ftp.zimmers.net/pub/cbm/transfer/datassette/) and Audiotap (http://wav-prg.sourceforge.net/) to convert my wav file to tap.  Both seem good.  Tape64 provided the breakthrough because it allowed me to adjust the speed to 1.1.  It took a lot of experimentation to convert the file properly.  I also had to learn not to worry when the VICE emulator showed the contents of my file as “EMPTY IMAGE.”


As I mentioned before, VICE is a very impressive emulator.


This stuff is all free, as is Star Worms, but the other programs are really good.


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