The YM2612 Information Thread

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Count SymphoniC
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Post by Count SymphoniC » Wed Oct 08, 2014 4:32 pm

Is it done by reading the VDP status register? I see that bit 0 is the PAL bit.

From the VDP wiki:
PAL seems to be set when the system's display is PAL, and possibly reflects the state of having 240 line display enabled. The same information can be obtained from the version register.
Does this mean when the console itself is in PAL mode, or the TV it's hooked up to?

r57shell
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Post by r57shell » Wed Oct 08, 2014 5:57 pm

As far as I understand, sega video signal output only, so it's your TV detecting type of signal.
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TmEE co.(TM)
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Post by TmEE co.(TM) » Wed Oct 08, 2014 6:32 pm

You got two options. One is an IO register (same one you read te determine wether or not you write "SEGA") and other is VDP status port.

IO register gives settings of region info (two bits, one for Eng/JP, other 50/60) and VDP register definite 50/60 setting.

If you are only gonna differentiate 50/60 I suggest using VDP register for that, it cannot be fooled by modding tricks :P
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Jazzmarazz
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Post by Jazzmarazz » Wed Oct 08, 2014 9:06 pm

powerofrecall wrote:
Jazzmarazz wrote:Half the time I don't know if you're being an ass
He's a good guy. I think it's a cultural thing, and his English is better than my Russian!
I can make the same claim! :lol:
r57shell wrote:
Jazzmarazz wrote:Half the time I don't know if you're being an ass, but it probably the poor English. Lunks to code supporting an auto region check within a ROM?
My english is bad, yes. But I don't worry about it. Also, I'm not so stupid to add in signature "sorry for my bad eng" :D

If you wanna example, try to run Comix Zone (J) with PAL Megadrive :). You'll see something like "It's developed for NTSC only".

Most of difference in sound you'll get if you use VBLANK counter, because it's 60 Hz vs 50 Hz. Most of games using VBLANK as main timer has different speeds in gameplay on different regions. I know only one example where speed of gameplay is same: UMK3. But even there, timer of round is different. And if you check MK3 (E) vs MK3 (U) you'll see very strong difference in gameplay timing. I think, reason why gameplay timing is different NTSC vs PAL: developers of that time didn't notice or just didn't have BOTH consoles at place where they develop games.
Alright, cool. As long as there wasn't any harm intended I do respect your replies. You can understand how I would take offense to "of course, how do you not already know?" :lol:

In any case, "It's developed for NTSC only" makes sense.
TmEE co.(TM) wrote:You got two options. One is an IO register (same one you read te determine wether or not you write "SEGA") and other is VDP status port.

IO register gives settings of region info (two bits, one for Eng/JP, other 50/60) and VDP register definite 50/60 setting.

If you are only gonna differentiate 50/60 I suggest using VDP register for that, it cannot be fooled by modding tricks :P
There we go. Thanks for clarifying.

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