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NFG Forums => RGB + Video Discussions => Topic started by: Cyber Axe on April 13, 2006, 02:01:36 AM

Title: SNES RGB Aspect Ratio signal
Post by: Cyber Axe on April 13, 2006, 02:01:36 AM
i was just wondering since with RGB a signal is sent to tell the tv what aspect ratio it whould be run in (at least with UK SCART)

if anyone know if there was a way to change this for the snes since by default it seems to be sending a 16:9 signal and since its 4:3 its annoying haveing to change ti everytime i stick in a snes game

i'd imagine its just a matter of changing the voltage on one of the wires/pins so that the TV detects it as 4:3?
Title: SNES RGB Aspect Ratio signal
Post by: Hojo_Norem on April 13, 2006, 04:33:53 AM
The pin that is causing this in this case is pin 8, which is used to both tell the TV to switch to the scart and select the aspect depending on the voltage (the specifics escape me ATM)

If you are not bothered about your TV auto switching to the scart then just cut the connection to pin 8.
Title: SNES RGB Aspect Ratio signal
Post by: viletim! on April 13, 2006, 09:11:46 PM
On widescreen TVs the voltages on SCART's pin 8 should be:
0-2v for internal video (tuner)
4.5-7v for external video (16:9) mode
9.5-12v for external video (4:3) mode
most 4:3 TVs don't have a widescreen mode

I'm a bit surprised that you're having problems with your SNES. It's one of the few game consoles that tries to get the switching voltage within spec (it seems to use some kind of charge pump circuit to make ~12v from 5v). If you can, try to measure the voltage on pin 8 while the console is connected to the TV.