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Asterock

Sidam, 1979

Atari’s Asteroids was a huge hit and demand for the game was higher than Atari could build them for a while so quite a few bootleg manufacturers built a variety of bootleg Asteroids, frequently ghastly ones (to my eyes) hooked up to walls. The Italian manufacturer Sidam however went another route entirely: it built custom, dedicated arcade bootleg cabinets of very high standards. Everything – cabinet, control panel, coin door, pcbs, power supply, even the game roms themselves are customized. The latter is really interesting to me: they actually disassembled the original, rev1 game roms, adapted them to their needs and reassembled new versions. That’s impressive.

I don’t have access to an Asterock but do to a close sibling – Sidam’s Magic Worm: same cabinet style, coin doors and similar power supply in there. The coin doors and coin receptacle they used are really nice – nicer than Atari Asteroids’ ones – and the power supply a huge, dedicated brick. I would even go so far to say that Sidam’s coin door is nicer than the original ‘owl eye’ coin door of lunar lander and the very first Asteroids cabinets: it is and feels that solid.

For some reason the freeplay option was eliminated in Asterocks, too, and the one online version I found was less than optimal – the credit counter is still displayed, ignored and decremented – so I’ve made another one. Very simple: searched for this annoying credits output and substituted the code with an automatic ‘2 credits’ entry, similar to the freeplay dip switch behaviour on Atari Asteroids. If you happen to have an Asterocks and would like to try this freeplay version you only have to patch 6 consecutive bytes in the very first ROM in the cpu rom adr. range:

$68C3   $A9 $02       LDA #$02     ; 2 credits
$68C5   $85 $6F       STA $6F      ; into the credits counter
$68C7   $D0 $1D       BNE $68E6    ; and bypass all the credit output

If you are planning to change this rom with a hex editor it might be helpful to know and check against the original contents so here they are:

$68C3   $A0 $08       LDY #$08     ; 8 == 'credits' text id
$68C5   $20 $36 $78   JSR $7836    ; print out in selected language
$68C8   $A9 $90       LDA #$90
$68CA   $A2 $30       LDX #$30
$68CC   $20 $10 $7C   JSR $7C10

Just another curiousity but I do know that a few VecFever found their way into the hands of Italians so with Asterock they can play Asteroids in their native language, too.

a working Asterock pcb comfy in its cabinet

Input

Attract

  • 2: start two player game
  • 4: start one player game

In-game

‘Buttons’ input option

  • 1: turn left
  • 2: turn right
  • 3: thrust
  • 4: fire
  • holding all four buttons: hyperspace
  • joystick y: hyperspace

‘Digital Joystick’ input option

  • joystick left: turn left
  • joystick right: turn right
  • 2: hyperspace
  • 3: thrust
  • 4: fire

‘Analog Joystick’ option

  • Joystick: ship swivels to the direction pointed towards
  • 2: hyperspace
  • 3: thrust
  • 4: fire

Options

  • Brightness: Debris / Playfield / Ship&UFO / Shots
  • Input: Buttons / Digital Joystick / Analog Joystick
  • Language: English / French / German / Italian (!)
  • Lives: 3 / 4
  • Reset Highscores
  • Speed: Normal / Slower / Faster / Faster, NMI-Hack
  • Text: Normal / Terse
  • Game Info: ”                           Welcome to SIDAM’s Asterock, an interesting bootleg of the rev. 1 Atari Asteroids ROMs. SIDAM has built exceptionally nice, dedicated bootleg cabinets of various, early Atari games with in somce cases slightly weird control panels: Asterock for example uses one that is partly tilted downwards towards the back, a slightly strange experience.                In later Atari games they generated new ROMs to change the sound chip used from the pokey to something else so they had to disassemble, understand and change the games. Interestingly as I now saw they already did this for Asterock, too: this is not a patched romset but a newly assembled, slightly changed version of the rev.1 Atari romset. The vector rom is nearly identical apart from once vector and the copyright text. The game code has changed quite a bit, though, esp. the DIP switch code and the substitution of Spanish for Italian plus the removal of the freeplay option (added manually again here, as usual).                                        “

Localization

//NAME="ASTEROCK"
//

GERMAN[] = {
    { 0, 0, "Geschwindigkeit"},
    { 0, 0, "Langsamer"},
    { 0, 0, 0},
    { 0, 0, "Schneller"},
    { 0, 0, "Schneller, NMI-Hack"},
    { 0, 0, "Helligkeit"},
    { 0, 0, "Schüsse"},
    { 0, 0, "Spielfeld"},
    { 0, 0, "Schiff/UFO"},
    { 0, 0, "Explosionen"},
    { 0, 0, 0},
    { 0, 0, "Text: Gekürzt"},
    { 0, 0, 0}
};

FRENCH[] = {
    { 0, 0, "Vitesse"},
    { 0, 0, "Plus Lente"},
    { 0, 0, "Normale"},
    { 0, 0, "Plus Rapide"},
    { 0, 0, "Plus Rapide (NMI)"},
    { 0, 0, "Luminosité"},
    { 0, 0, "Tirs"},
    { 0, 0, "Aire de Jeu"},
    { 0, 0, "Vaisseau/OVNI"},
    { 0, 0, "Débris"},
    { 0, 0, "Texte: Normal"},
    { 0, 0, "Texte: Concis"},
    { 0, 0, "                           Bienvenue dans Asterock de SIDAM, un intéressant plagiat de la ROM d'Atari Asteroids révision 1. SIDAM a construit des bornes particulièrement réussies dédiées à divers anciens jeux piratés d'Atari, avec, dans certains cas, des panneaux de contrôle quelque peu bizarres : Asterock, par exemple, en utilise un qui est partiellement incliné vers l'arrière,  ce qui se traduit par une expérience de jeu assez particulière. Dans les jeux d'Atari plus récents, les programmeurs ont généré de nouvelles ROMs dans le cadre du remplacement de la puce sonore issue du Pokey;  aussi,  ils ont dû démonter, comprendre et modifier les jeux. Il est intéressant de constater qu'ils avaient déjà fait cela pour Asterock : il ne s'agit pas dans ce cas d'une rom patchée, mais d'une version nouvellement assemblée et légèrement modifiée de la rom d'Atari rev.1. La rom vectorielle est presque identique à l'exception d'un vecteur et du texte relatif aux droits d'auteur. Le code du jeu a cependant beaucoup changé, en ce qui concerne en particulier le code du commutateur DIP, le remplacement de l'Espagnol par l'Italien, ainsi que la suppression de l'option de partie gratuite (rajoutée à nouveau manuellement, comme d'habitude).                                         "}
};

ENGLISH[] = {
    { 0, 0, "Speed"},
    { 0, 0, "Slower"},
    { 0, 0, "Normal"},
    { 0, 0, "Faster"},
    { 0, 0, "Faster, NMI-Hack"},
    { 0, 0, "Brightness"},
    { 0, 0, "Shots"},
    { 0, 0, "Playfield"},
    { 0, 0, "Ship/UFO"},
    { 0, 0, "Debris"},
    { 0, 0, "Text: Normal"},
    { 0, 0, "Text: Terse"},
    { 0, 0, "                           Welcome to SIDAM's Asterock, an interesting bootleg of the rev. 1 Atari Asteroids ROMs. SIDAM has built exceptionally nice, dedicated bootleg cabinets of various, early Atari games with in somce cases slightly weird control panels: Asterock for example uses one that is partly tilted downwards towards the back, a slightly strange experience.                In later Atari games they generated new ROMs to change the sound chip used from the pokey to something else so they had to disassemble, understand and change the games. Interestingly as I now saw they already did this for Asterock, too: this is not a patched romset but a newly assembled, slightly changed version of the rev.1 Atari romset. The vector rom is nearly identical apart from once vector and the copyright text. The game code has changed quite a bit, though, esp. the DIP switch code and the substitution of Spanish for Italian plus the removal of the freeplay option (added manually again here, as usual).                                        "}
};
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