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Atari, 1980, Tempest prototype

The Vortex prototype game is pretty close to Tempest and feels polished and almost the same as the final game so the most important difference is besides the name the different title animation – on the actual Tempest pcb Vortex would output even more logo strings and the phosphor would keep them around a bit longer, too, but for the Vectrex output I opted to use a more stable output by keeping the animation but limiting the output a bit.

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:


  • Reset Scores
  • Language: English/Spanish/French/German
  • Demo Mode: On/Off (Level Skip)
  • Input: Analog Joystick (Port 1), Atari Driving Controller (Port 2), Digital Spinner with 2 buttons (Port 2)
  • Level: Vortex/Vortex Tubes
  • Lives: 3/4
  • Game Info



GERMAN[] = {
    { 0, 0, 0},
    { 0, 0, 0},
    { 0, 0, "Demo Modus: An"},
    { 0, 0, "Demo Modus: Aus"},
    { 0, 0, "                           Willkommen zu Vortex, einer Prototypversion von Tempest.                Vortex ist recht nah an der finalen Version, da sind einige, wenige Änderungen an den Leveldaten, kein Sicherheitscode, Änderungen am Attract (z.B. spielt es waiter, falls der nächste Level erreicht wird) und natürlich der andere Name. Demomodus ist auch anders und sicher noch etliche andere Kleinigkeiten aber im grossen und ganzen fühlt es sich wie Tempest an. Vielleicht etwas schwerer aber das kann auch an den fehlenden Schwierigkeitseinstellungen liegen, denn ich spiele Tempest immer auf 'Einfach'.                     Dies zu portieren war hauptsächlich nur Neugier um zu sehen, was anders ist... Auch und gerade, da Vortex im Moment (2021) immer noch nicht von MAME emuliert wird, ich es also noch nie vorher sah.                     "}

FRENCH[] = {
    { 0, 0, "Niveau: 'Vortex'"},
    { 0, 0, "Niveau: 'Vortex Tubes'"},
    { 0, 0, "Mode Démo: Activé"},
    { 0, 0, "Mode Démo: Désactivé"},
    { 0, 0, "                           Bienvenue dans Vortex, un prototype de Tempest.                 Vortex est assez proche de la version finale: il y a quelques changements concernant les données de niveau, l'absence de code de protection, des changements également pendant le mode attractif/Démo (par exemple le fait de continuer à jouer au niveau supérieur s'il est atteint) et bien sûr le nom qui n'est pas le même. Le mode 'Démo' est également différent et je suis sûr qu'il y a plein d'autres petits écarts, mais dans l'ensemble, j'ai les mêmes sensations qu'en jouant à Tempest. Je pourrais le qualifier d'un peu plus difficile, mais c'est peut-être parce que je joue toujours à Tempest en mode \"Facile\" et qu'il n'est pas possible de régler la difficulté à l'aide de commutateurs DIP sur Vortex.                       J'ai abordé ce sujet par simple curiosité afin de découvrir en quoi Tempest et Vortex étaient différents... De plus, à l'heure actuelle, Vortex n'est toujours pas émulé par MAME, ce qui explique que je ne l'avais pas vu fonctionner auparavant.                     "}

    { 0, 0, "Level: Vortex"},
    { 0, 0, "Level: Vortex Tubes"},
    { 0, 0, "Demo Mode: On"},
    { 0, 0, "Demo Mode: Off"},
    { 0, 0, "                           Welcome to Vortex, a prototype version of Tempest.                Vortex is quite close to the final version, there are a few changes in the level data, no protection code, changes during the attract (e.g. keeps playing next level if it reaches it) and of course the different name. Demo mode also is different and I am sure there are a lot more small changes but overall feels and plays just like Tempest to me. Maybe a bit harder but this might be because I always play Tempest on 'Easy' and Vortex also does not have difficulty DIP switch settings yet.                     Bringing this up was more out of curiosity as to how this is different... Plus at the current time Vortex is not emulated by MAME so I had never seen it before myself.                     "}
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