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Atari, 1980, Tempest prototype

Aliens is the earliest, surviving development stage romset, ported out of curiousity to be a able to look at and compare the development stages of Aliens, Vortex and Tempest. Brutally hard since it has no auto-fire.

The preservation and naming of the romset was done by Clay Cowgill, who developed a Tempest Multikit to be able to play all these prototype version in a Tempest cabinet.

Vectorlist Archives: Aliens - update...Aliens - update...
From: Clay Cowgill <> 
Date: Thu Mar 18 1999 - 12:00:18 EST

Well, good news! 

I managed to sneak into the computer room and work with the Aliens 
boards a bit last night (we've had company all week so hacker-time has 
been limited). 

Long story short-- both sets of Aliens ROMs work, and are different! 
They also appear to run on stock Tempest hardware. (Yay! :-) 

I've dubbed the sets "Aliens Proto 4" and "Aliens Proto 5" based on the 
board serial numbers. 

Aliens Proto 4 appears to be the earlier set. It's smaller by 2K, and 
has a lot of unused space in the ROMs. It also appears to have been 
related to Lunar Lander somehow 'cause it appears there's chunks of 
Lunar Lander source code in the ROMs. Go figure. Gameplay is 
definately "Tempest", but seems REALLY hard. That could just be the 
fact that the shooter doesn't auto-fire - one bullet per press on the 
button! The game appears to be in some kind of early beta-state-- there 
is no title screen, enemy movement is slightly different (faster?), and 
all enemies but the red flippers "sparkle" instead of having solid 
colors. Explosions are also multi-colored, and the player "death" 
animation is completely different. I haven't tried it on a machine with 
sound capabilities yet, so I can't comment on that yet. Oh, yeah-- "NEW 
SUPERZAPPER" instead of "SUPERZAPPER RECHARGE". High-score table 
doesn't seem to be functional either. 

Aliens Proto 5 looks much closer to the released game. It does however 
have one obvious and cool difference-- the title screen proudly 
proclaims "VORTEX by Atari" in a cool-looking font. ;-) (Same sort of 
"zoom in" effect that the Tempest title screen does, but the "trails" 
 from the letters stay on screen for a while.) Once again, gameplay 
seems close to final Temest, but possibly a little harder. It may also 
allow more player bullets on the screen at once-- although that could 
have just been my perception after playing with Proto 4 for a while. 
Auto-fire works, and all the rest of the game functions seem 
more-or-less the same as Tempest. There's definately differences 
though, but until I do a side-by-side compare they're tough to describe. 

Anyway, this is just entirely too interesting (to me at least ;-) to 
pass up, so I'm putting together a multigame for all this stuff. It's 
not going to be super-fancy, but should serve its purpose-- a software 
based menu system allows selection of Aliens Proto 4, Aliens Proto 5, 
Tempest rev 1, Tempest rev 2, Tempest rev 3, and Tempest Tubes (if OK 
with author). There will be three jumpers on the board that allow 
selection of any game (or the menu) to be the default "power-up" mode of 
the cabinet. The menu will still be call-able from a dedicated 



The game supports either an analog Vectrex joystick plus its buttons to emulate the arcade spinner or uses a ‘grey code’ digital spinner, the ones used by Atari in their driving controller back in Atari VCS days (beware: there exists a similar looking Atari paddle controller).

The analog joystick emulation is the most precise in terms of positional input but does need a bit of getting used to since pointing to the left/right does not correspond with left and right on the screen.

The Atari driving controller has one button which can be used on the Vectrex even though it is not hooked up to a button input but rather the analog ‘Y’ input: the button for a given controller simply has to be pressed a few times to calibrate the pressed/not-pressed range. The super zapper button in-game with the driving controller is any buttons of port 1.

You can easily build your own digital spinner with 2 buttons in a small enclosure and a few people have done so which is the last input option supported, here superzapper/fire are mapped onto 3: and 4:


  • Graphics: Arcade/Vectrex
  • Language: English/Spanish/French/German
  • Input: Analog Joystick (Port 1), Atari Driving Controller (Port 2), Digital Spinner with 2 buttons (Port 2)
  • Lives: 2/3/4/5
  • Game Info



GERMAN[] = {
    { 0, 0, "                           Willkommen zu Aliens, eine sehr frühe Prototypvariante von Tempest. Interessantes historisches Relikt für Tempestfans und/oder falls man an Spielentwicklung interessiert ist: das Spiel ist zwar spielbar aber offensichtlich noch mitten in der Entwicklung. Die Titelanimation, Highscoremanagement, EAROM Unterstützung, mehr Töne sind alle bereits Teil von dem Vortex Prototypen aber hier noch nicht implementiert. Dieser Prototyp hat zudem einige Probleme, weshalb der Hardwarewatchdog der Tempestplatine ausgeschaltet werden muss. Und das Tempest sogar ohne Autofeuer anfing ist verrückt.                       "}

FRENCH[] = {
    { 0, 0, "                           Bienvenue dans Aliens, un des tous premiers prototypes de Tempest. Il s’agit d’une relique intéressante pour les fans de Tempest mais également pour tous ceux qui s’intéressent de façon plus générale à l’histoire du développement des jeux : Aliens est tout à fait jouable mais il est évident qu'il s'agit encore d'un travail non finalisé. Ainsi, l'animation du titre, le classement des meilleurs scores, le support d’une EAROM et l’intégration de nouveaux sons qui feront tous partie du prototype Vortex ne sont pas encore implémentés ici. Ce prototype présente en outre quelques problèmes, raisons pour lesquelles le chien de garde matériel de la carte Tempest doit être désactivé. Enfin, le fait de constater que Tempest ait pu commencer à exister sans tir automatique est tout simplement ahurissant.                     "}

    { 0, 0, "                           Welcome to Aliens, a very early prototype version of Tempest. Interesting historical relic for Tempest fans and/or if you are interested in game development history: the game is playable but still very obviously a work in progress. Title screen, high score management, EAROM handling, more sounds are in the later Vortex prototype but here all still missing. This prototype also has problems which result in the necessity to disable the hardware watchdog of Tempest. And that Tempest even started out without autofire is just crazy.                       "}
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