THE GREAT VOLCANO HUNTER HACK

Gary W. Shanafelt
McMurry University
Abilene, TX 79697
;LI8


There are a lot of definitions of ``hacker.''  I suppose in general a hacker is someone who tries to figure out how a computer program works by analyzing all the code modules in it.  My wife's definition is that I'm ``hacking'' when my Model 4 is on and I'm doing anything except word processing on it.  I was originally sucked into this form of computeritis because of various programs I had which used misspelled words, which I, as a teacher, couldn't stand seeing on my screen.  Being compulsive, I didn't like having some things on disk and others on tape, nor did I like protected programs since I wanted everything I had to run under the same operating system (which ended up being LDOS in Model III mode and LS-DOS in Model 4 mode).  Of course, I also had to figure out how to make a number of programs which ran on my original Model I also work when I replaced the Model I with my current Model 4.  I don't really know how much time and effort I spent on all this, especially when I embarked on a project of customizing all the arcade games I had to return to the DOS without the necessity of hitting the RESET button.  I do know that I spent more time hacking the games than I ever spent playing them.

I say all this by way of introduction because nothing I attempted ever came close to the time and effort a fellow named Kelly Bates put into hacking a game called Volcano Hunter.

Volcano Hunter was one of the last TRS-80 arcade games.  It was written by David Smith of Mississippi State University.  He was apparently a student there, for when I tried to write him my letters got returned with no forwarding address (which I assume means that he graduated).  I have no idea what he is doing now.  Volcano Hunter was never one of the big name games like Galaxy Invasion or Sea Dragon or Scarfman, perhaps because it appeared at the end of the TRS-80 game era, in 1984, though it got a four star review in the September 1984 issue of 80 Micro.

Most arcade games of the time followed one of several formats.  Aliens descended from the top of the screen while you shot at them from the bottom (like Missile Attack or Defense Command); or you scrolled sideways across an obstacle-filled landscape while aliens came at you (like Zaxxon or Penetrator or Eliminator); or you moved in four directions on the screen among obstacles and aliens (like Scarfman or Apple Panic).

Volcano Hunter fit none of these molds.  It was a sort of graphic adventure, like Zork might have been if it had somehow been converted into an arcade game from a text adventure.  There were some other TRS-80 adventure games with graphics, like MED Systems' Asylum or Warriors of Ras series, but nothing with the graphics of Volcano Hunter.  In it, you explored the innards of a Volcano to retrieve fuel canisters and gold.  Those innards were replete with lava, water-filled chambers, ladders, dead ends, moving conveyer belts, drop-offs, and, of course, the Drut monsters.  Your screen would show you one small part of this underground maze; you saw other parts as you advanced in different directions.  The trick was to figure out how each part you saw fit together like the pieces of a puzzle, so you learned the best ways to penetrate the world inside the volcano as well as how to get back out with your fuel canisters.  Since you only got eight men, most people probably never realized just how complex the whole Volcano world was because they got zapped before they ever managed to explore very far.  Advertisements for Volcano Hunter said that it comprised over 200 screens -- a real tour de force for a program of just 16K -- but most of those screens were probably never seen except by the program's author, David Smith... and Kelly Bates.

Who was Kelly Bates?  I never met him.  Though he is now on his second MS-DOS machine, he still tinkers on a Model 4P and attends a user group in Oklahoma City, where he resides.  I got to know him five years ago through the mail after I acquired a tape version of Volcano Hunter (which I transferred to disk) and began asking around to locate someone with a disk version.  I wanted to know how the two were different, since the disk version was supposed to have various enhancements absent on the tape one (as it turns out, it just had a few more screens).  Kelly also had the tape version, and what he had done with it was truly amazing.

What he had done was to determine to find out just what all 200-plus screens of Volcano Hunter looked like or die in the attempt.  Arcade games back then often aroused strange passions in people: I remember staying up all night once trying to discover what lay at the end of Sea Dragon, and exhausting myself trying to get to 50,000 points on Galaxy Invasion Plus to see the screen flip around.  It didn't take Kelly long to realize that he could never get through the entire volcano with just eight men.  So, he went into the program code with the Newdos diskzapper SUPERZAP, found where the A register was loaded with the number of men and then decremented, and nulled the decrement instruction.  That meant the men counter was always set at eight no matter how many times he was destroyed by the Druts or the heat from the lava or drowning in the underground pools.  Slowly, he explored and mapped out the whole grid.  He discovered several fuel cells which were totally sealed off, as well as how the whole program worked.

But that was just the beginning.  To make the game easier to play, he began studying how the various screens were mapped in the program code, so that he could modify the grid.  Each screen, he found, consisted of three rows of eight hex characters each, for a total of 24 bytes.  Each byte was a special code for a portion of a wall, a hot spot, a fuel cell, a ladder, etc.  The program read the 24 bytes for each screen, then matched them with their equivalent graphics characters to form a new picture on the screen.  Armed with this information, he could basically create any pattern of screens that he wanted.

But like any TRS-80 devotee, Kelly was not content to rest on his laurels.  He wanted to see what the entire grid looked like as a whole, not in 200 separate pieces.  With Karl Hessinger's graphics editor ZGRAPH, he replicated all the graphics blocks used in Volcano Hunter to create the individual screens.  He then converted those designs into characters for a Dotwriter font which he called, appropriately, VOLCANO/PR.  Finally, with the new font and Dotwriter, he printed out the entire 200-screen grid on his Gemini printer.  It took several pages which he then taped together... and he had the only map in existence of all the byways of Volcano Hunter.

He says it all took him about two years, and he made his final printout on February 18, 1986.  When he sent me a copy, I was totally amazed.  I was amazed first of all at the sheer work involved, but I was also amazed at just how incredible a program Volcano Hunter actually was.  Like most people, I had never realized how much was there.  Armed with Kelly's map, I went into that volcano to explore new worlds where no one (except Kelly) had ever gone before.

The glory days of the TRS-80 are over, but I hope that some of the deeds it inspired will be remembered even when no one any longer remembers things like expansion interfaces or supervisor calls.
