The Italian arcade manufacturer Sidam built quite a few dedicated, quite interesting bootleg cabinets of Ataris early games, including an Asteroids clone. The cabinet quality was excellent, I actually think they are as nice as the originals. However they were also quirky: Asterocks for example uses a control panel which tilts down towards the back, very odd. I have yet to see an Asterock but Sidam Magic Worm has a similar panel style and this actually works quite well there – it feels like it draws me physically into the game. And they didn’t just patch the original roms – they disassembled the originals, adapted the code to suit their purposes and reassembled new romsets. Same for Asterocks: this is a changed, reassembled Atari rev.1 romset with a few changes, most notably the substitution of the Spanish language setting with Italian.
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 on the Vectrex really.. but I do know that a few VecFever found their way into the hands of Italians so now they can play Asteroids in their native language, too, since I have just added the asterock romset handling to my asteroids tools/emulators. I have used the rom zip file on andysarcade.de -only renamed from asterock_roms.zip to asterock.zip. And here is the emulator itself: