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Image shifted in 15kHz mode on a CRT TV #10

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@phoboz

BTW does anyone know why most cores are off-centered on my old PAL TV (a part of the picture is missing on the left on the NES, PCE & MD cores) while I have the whole picture perfectly centered with Amiga & ST cores ?

In order to exclude that this has to do with 50Hz(PAL) vs. 60Hz(NTSC), can you try the Sega Master System (mist sms) core with scandoubler_disable?
In that core you can switch beteween NTSC and PAL.

Hi ! I checked ! So with the SMS and Amiga core, when switching to NTSC, the picture is still perfectly horizontally centered. With the PCE, NES and MD cores, at 60 Hz, the picture is cropped on its left.

The genesis core generates simpified sync signals, while the sync signals are more complex for the sms core. The simplified sync signal works fine on my flatscreen TV, but maybe it doesn't on a CRT TV. There are also differances to when the first sync pulse is sent, so this might shift the image starting position? I will create an issue for this in the fpgagen repository, but a change to this will require a lot of work due to how this was already implemented in fpgagen, and it hasn't the highest prio for now.

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