corrupt VRAM on some title screens

[Memblers]

With V1.8, I'm seeing corrupt VRAM on the following games:
10-Yard Fight
Mach Rider (PRG0)
Soccer
Dragon Quest II
Magmax
Wild Gunman (PRG1)
Urban Champion
Zippy Race

And separately:
Pac-Land (scrolling problem)

I don't know if that helps, but I can look for more. Fascinating project.

[Memblers]

I was able to find a couple different issues also:

Baseball (goes straight to gameplay, skipping title screen)
Ikari Warriors (high pitched tones throughout audio)

Burgertime (displays black screen)
Choujikuu Yousai - Macross (displays black screen)
F-1 Race (displays black screen)
Front Line (black background on title screen, display problems in demo. this game goes into attract/demo mode relatively quickly)

Door Door (hangs? this game depends on frame IRQ)
Lunar Pool (hangs? palette doesn't change)

corrupt VRAM:
Formation Z
Field Combat
Ikki
Lode Runner

[ogamespec]

Thanks for the findings, we'll look into it :)

[ogamespec]

Fixed in #403

As long as you can use Famicom (HVC-CPU-01 in Settings) for (J) roms, it is not affected by this bug.

This is only with regard to the garbage on the screen and strange hangs. In more detail I will look at individual cases, for example in Lode Runner for some reason the Scroll is broken... but this is related to something else.

[ogamespec]

Checklist:

• 10-Yard Fight
• Mach Rider (PRG0)
• Soccer
• Dragon Quest II
• Magmax
• Wild Gunman (PRG1)
• Urban Champion
• Zippy Race
• Pac-Land (scrolling problem)
• Baseball (goes straight to gameplay, skipping title screen)
• Ikari Warriors (high pitched tones throughout audio)
• Burgertime (displays black screen)
• Choujikuu Yousai - Macross (displays black screen)
• F-1 Race (displays black screen)
• Front Line (black background on title screen, display problems in demo. this game goes into attract/demo mode relatively quickly)
• Door Door (hangs? this game depends on frame IRQ)
• Lunar Pool (hangs? palette doesn't change)
• Formation Z
• Field Combat
• Ikki
• Lode Runner