Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!unmvax!ncar!ames!amdcad!sun!pitstop!sundc!seismo!uunet!mcvax!unido!rmi!kkaempf From: kkaempf@rmi.UUCP (Klaus Kaempf) Newsgroups: comp.sys.amiga Subject: Re: Bug in decision for PAL or NTSC Message-ID: <1329@rmi.UUCP> Date: 7 Dec 88 14:56:01 GMT References: <1994@van-bc.UUCP> Reply-To: kkaempf@rmi.UUCP (Klaus Kaempf) Organization: RMI Net, Aachen, W.Germany Lines: 29 In article <1994@van-bc.UUCP> lphillips@lpami.van-bc.UUCP (Larry Phillips) writes: : : > But what is the 'line frequency' pin from the power supply good for ?? : > Doesn't the Amiga check that line to decide if it should display PAL (50Hz) : > or NTSC (60Hz) ? : : I hope not. This would prevent PAL Amigas from being used in North America, : and NTSC Amigas from being used in Europe. : Europeans is that some (many?) programs developed in North America don't : look right on PAL systems, but at least a few vendors have PAL Amigas to : test with, and it has to help the situation a bit. : : -larry To clarify: PAL == 256 lines/frame, NTSC == 200 lines/frame. PAL -> 50 Hz -> 25 frames/sec -> 6400 lines/sec NTSC -> 60 Hz -> 30 frames/sec -> 6000 lines/sec So both need about the same dma bandwith to display a standard picture. You can't display 256 lines with NTSC, can you ?? By looking at the line frequency at boot-time, the amiga should decide whether to display 200 lines (60 Hz, no dma-time for 256 lines) or 256 lines (50 Hz, no 200 lines please !). Still puzzled, Klaus