[stella] PAL/NTSC Auto-Detect (Needs testing on PAL)

Subject: [stella] PAL/NTSC Auto-Detect (Needs testing on PAL)
From: Christopher Tumber <christophertumber@xxxxxxxxxx>
Date: Fri, 15 Nov 2002 17:27:01 -0500
I believe Christopher Rydberg was looking at this about a year ago, but checking through the archives it doesn't look like it ever worked out(?). If so then I've just spent the afternoon in duplication of effort, not the first time, that's for sure...

So here's a preliminary proof of concept, there's quite a bit of extraneous code (I've really just ripped out the score display code and hacked it to work) so I'll wait to post source once I have it cleaned up. But I don't want to take the time to do that until I have a better idea if this is actually works...

This just uses the Kool-Aid Man score display code for one frame and then checks the collision detection latches. It should display either PAL or NTSC (as text) according to the hardware present.

- It does display NTSC on my hardware.
- It displays PAL on every emulator I've tried (Of the emulators I've tried (StellaX, Pcaewin and z26) only z26 displays Kool-Aid Man correctly. However z26 cheats!! It's not actually doing the emulation it's just detecting the presence of the Kool-Aid Man rom (presumably through checksum because changing even 1 byte in Kool-Aid Man makes z26 display incorrectly as per the other emus) and then compensates to the undocumented bahaviour. Boy did I ever waste a bunch of time trying to extract the code and test it on z26 before realising this!! (smile))

Anyway, I'd appreciate if someone could run this on PAL hardware and let me know if it comes up displaying PAL (will still display 262 scanlines regardless)


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