If not for the Framemiester I never would have known this was a thing. It takes a few seconds for the Framemiester to get a console's Video signal. Trying to make it instant is how I found this uh...thing. While messing around trying to get my Super Famicom looking perfect I noticed sometimes I'd get a reset that doesn't disconnect the Video signal and others I would. Other than the signal there is no other difference. A light tap doesn't interrupt the signal a long press does. It's the same way on the N64. So what is going on here?
you are still resetting the video output but it's so fast that the framemister doesn't have time to unlatch
It's a Framemeister thing. It won't stop outputting video until it's interrupted for long enough. In my case, when capturing for Youtube, this was helpful when trying to capture something that appears right when the system powers on, like the Neo Geo CD startup screen.
When I was younger I always assumed reset buttons worked like momentary power switches but obviously that is wrong. How the hell does Genesis X-men use the reset button as another input button? How do some NES games flag the number of times reset is pressed to access specific functions, yet some others will freak out and access portions normally inaccessible (like some unlicensed game menus)?
You don't have the button reset the whole system but just the CPU. That way RAM contents survive (for an extreme case of this, see "stop-n-swop"), and you can check for and use them when your code boots back up. (and if you eff up that "is-memory-already-initalized" check, bad things can happen.)
Depends on the system. In some systems the reset button is nothing more then a switch that triggers a software interrupt, in some it cuts power forcing a restart of the system and in some it just forces the jump back to the boot entry point. Even if it is an interrupt version, there are cases where games will handle it poorly and trash/rebuild the engine resulting in a resetting of the video hw state which effects things like upscalers.
How did the 64 handle reset? Remember on MARIO 64 when you hit reset the image would do this venetian blinds effect.
Probably by not reinitalizing the framebuffer on startup/reset, leaving the last image intact - and then if it recognizes it's been reset it starts blanking out lines to create that effect on top of whatever image was left over from before. edit: Actually, nope - On the 64 you get a reset exception that you can react to however you wish.
