VDP zoned ?

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VDP zoned ?

Post by ElBarto » Wed Jul 16, 2008 11:56 am

After reading Charles MacDonald vdppin.txt I was wondering something.
He says that the pin #46 is the /PAL input, when low generate PAL timing or NTSC timings when high.
Do you know if it's tight to GND on a PAL console or it's the same line than the region JPX that is used for the region mod ?
Another question, what appended if you select a PAL only display on a genesis ?

Jorge Nuno
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Post by Jorge Nuno » Wed Jul 16, 2008 12:48 pm

It's tied together with the color encoder and the bus manager and finally the famous copper-jumper.

If you force NTSC mode on a 240 cell display the picture will roll (seems to be absence of Vsync, but I haven't scope it)

TmEE co.(TM)
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Post by TmEE co.(TM) » Wed Jul 16, 2008 8:33 pm

240 in NTSC gives a rolling picture... Vint seems to be happening like 30 times a second, at least games that use Vint for music get really slow music.
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