MAMEWorld Forums - EmuChat - Re: netlist audio goodness here

>> 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.

https://www.youtube.com/watch?v=sgnkIBbsKf8

Thanks for taking a look at the video emulation and observing and describing the Destroyer video behavior.

I believe your take on this should be worthy of adding to info regarding Atari Destroyer. That way it will prevent any possible future false positive bug reports from happening.

>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.

Heh. In a way this reminds me of going back to around 2003 or 2004 on Gridle's old MAME.net forum days. At the time, many including myself were posting in a particular thread guessing Kee Games Quiz Show didn't use a cpu. Al Kossow joins in the thread with his post explaining Quiz Show uses a s2650 cpu. The Quiz Show service manual seems to maybe be intentionally designed to be obscure since lots of info seems vague as what someone had described to me in the past.

>> 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.

Okay. That's what I was guessing. Midway Checkmate is another game with same issue of missing a language option rom.