Wrong aspect ratio on Sega CD games

[rigues]

Hi Folks,

I’m setting up a RaspBerry Pi as an “emulation machine” with RetroPie 2.2, and I ran into an issue with Sega CD emulation with PicoDrive: the games are running at the wrong aspect ratio (stretched to 16:9 on my TV), even if I manually specify a ratio on retroarch.cfg with the video_aspect_ratio parameter. I tried both a numerical value (like 1.333333) and core provided ratios to no effect.

Another smaller issue with PicoDrive is that it seems to be cropping a few lines (guess about 16) from the top and bottom of the image. This is most visible in games which put the scoreboard on top, like Ninja Gaiden II on the SMS or Gleylancer on the Genesis.

The Raspberry Pi runs on my TV at 1280 x 768 with an overscan of zero, and the EmulationStation interface is _not_ cropped. I tried playing around with the overscan parametes on /boot/config.txt, but even after adding an overscan of, say, 16px on top and bottom of the screen Picodrive still crops the image inside the visible area.

Any ideas or pointers would be greatly appreciated. This forum has been an invaluable resource during my experiments.

[trimmtrabb]

try changing runcommand.sh to 2 in es_systems.cfg located in /etc/emulationstation/

More info here: https://github.com/retropie/RetroPie-Setup/blob/master/supplementary/runcommand.sh

If that doesn’t work there is an option to change aspect ratio in the Retroarch GUI

[rigues]

trimmtrabb,

Thanks! runcommand was set to 1 (switch to VGA), and setting it to 2 fixed the aspect ratio on Sega CD AND the cropping on SMS and Megadrive (both were set do 4 which switches to CEA Mode 4, my Pi is running on DMT mode 23). I also went ahead and fixed it for the 32x as well (it was also set to 1).

Do you know why the default behaviour is to change resolution before running a game?

Regards,

[trimmtrabb]

Glad you sorted it :-) The runcommand script switches the resolution down to VGA for better performance though I haven’t noticed any difference to be honest, maybe a small increase with N64/PSX emulation but nothing dramatic.

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