> The other issue that I remember about Atari Destroyer is the video code is from late > 1990s and for some unknown reason the 'Atari copyright' text image doesn't appear on > the attract mode segment of Atari Destroyer. 'siftware' had dumped his Destroyer pcb > years earlier and indicated how his pcb does show the copyright text image. iirc his > Atari Destroyer pcb rom set was eventually added to MAME support. > > I don't know if the copyright text appears or not when running Destroyer, but if not > then likely some video emulation issue from the older era code.
While working on this game's emulation recently, I found that the copyright text is drawn in the left corner at the beginning of the VBLANK area. VBLANK timing is determined by a bipolar PROM on actual hardware, but postponing its start puts it out of sync with scanline interrupts, causing the game to glitch unplayably.
Video of an actual Atari cabinet doesn't show anything like the text, and the cabinet art would make it very hard to see there. Most likely, it's just another trap Atari laid for bootleggers in an era when Atari was clearly worried about video game code not having adequate legal protection.
https://www.youtube.com/watch?v=sgnkIBbsKf8
> The other thing I remember about Atari Destroyer is there was a language rom option > in which operators could request the language rom as an extra item. I am not sure if > that is supported yet or if that is a rom that has yet to be dumped and supported.
The language ROM (030138) simply hasn't been dumped yet.
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