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Reply To: 1920 lines horizontal sampling/output for all inputs + aspect ratio controls

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#14644

awe444
Participant

Do you know whether 512-column PS2 games use different dot clock than usual 480i games (858 dots per line), or whether PS2 internally scales framebuffer width to usual 640/720 output

I investigated this a while back and measured the following dot clock rates for the PS2’s interlaced modes (assumes a 27MHz source crystal combined with observations from manually tuning the OSSC sample rate on appropriate pixel patterns):

512x480i : 686.4 dots/line = (27MHz * (2/5) / (4.5MHz / 286))
640x480i : 858.0 dots/line = (27MHz * (1/2) / (4.5MHz / 286))

For progressive mode however, both 512 and 640 width games are output in 800 dots/line (the 512 wide games get black borders on the sides).