Full VGA resolution (640x480) 3.5" display, composite in

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dirtybeagles
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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by dirtybeagles » Thu Jun 09, 2016 8:07 pm

Just FYI... not sure why it makes a difference but I had to connect the pi0 to my breakout board instead of the power boost

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by joe7dust » Thu Jun 09, 2016 9:49 pm

Does this add any benefit when playing games on retropie? I thought all the content was 320x240 ... if it gets up-scaled by this display, is the quality noticeably better than with a "normal" screen? If its not the display, but the pi0 that is doing the up-scaling, I wonder if it has a performance impact...

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Ganreizu » Thu Jun 09, 2016 10:38 pm

Cannikin wrote:
Mad_Duke wrote:Unfortunately no. If you do "display_rotate=2" then when you plug in the HDMI it will also be rotated.
Right, but I'm saying that you don't need display_rotate at all, IF you don't have to flip your screen inside the GB. I have room in mine for the ribbon to go at the bottom, but it just seemed a little "cleaner" at the top. And I'm not exposing the HDMI port, so I won't have to worry about the fact that it would be rotated if I plugged in an external screen.
The screen itself looks REALLY off with ribbon on the bottom though. You' be forced to put electrical tape on that metal because it would look suuuuper weird through the screen window. Also ribbon on top is a better fit IMO.

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Cannikin » Thu Jun 09, 2016 11:48 pm

joe7dust wrote:Does this add any benefit when playing games on retropie? I thought all the content was 320x240 ... if it gets up-scaled by this display, is the quality noticeably better than with a "normal" screen? If its not the display, but the pi0 that is doing the up-scaling, I wonder if it has a performance impact...

Check out my post over in the Alternative Displays thread. I've got photos and a video showing them side-by-side.

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Mad_Duke » Fri Jun 10, 2016 5:26 am

joe7dust wrote:Does this add any benefit when playing games on retropie? I thought all the content was 320x240 ... if it gets up-scaled by this display, is the quality noticeably better than with a "normal" screen? If its not the display, but the pi0 that is doing the up-scaling, I wonder if it has a performance impact...
It would benefit because the Pi is sending a resolution of something similar to 704×576 (at work now so can't say) through composite. so 640x480 is closer when downscaling because basically even if the content is 320x240 it is first upscaled to ~~ 704×576 and then again downscaled in the screen to 320x240. Which is a big loss of quality and it would be a lot less if it was downscaled from ~704×576 to let's say... 640x480

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by joe7dust » Fri Jun 10, 2016 5:30 am

Mad_Duke wrote:
joe7dust wrote:Does this add any benefit when playing games on retropie? I thought all the content was 320x240 ... if it gets up-scaled by this display, is the quality noticeably better than with a "normal" screen? If its not the display, but the pi0 that is doing the up-scaling, I wonder if it has a performance impact...
It would benefit because the Pi is sending a resolution of something similar to 704×576 (at work now so can't say) through composite. so 640x480 is closer when downscaling because basically even if the content is 320x240 it is first upscaled to ~~ 704×576 and then again downscaled in the screen to 320x240. Which is a big loss of quality and it would be a lot less if it was downscaled from ~704×576 to let's say... 640x480
Good explanation. Is PiTFT 480p not possible then?

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by dirtybeagles » Fri Jun 10, 2016 5:54 am

Cannikin wrote:[mention]Mad_Duke[/mention] and [mention]dirtybeagles[/mention] you only need display_rotate=2 if you mount your screen "upside down" (ribbon cable at the top). If you can mount it with the ribbon cable at the bottom then no need to rotate at all. :)
I have this option on my display.. it seems to rotate the screen natively so I don't have to make any change to the config on the pie.
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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by Mad_Duke » Fri Jun 10, 2016 6:24 am

Which display? Please :) I'm ordering mine tomorrow (because present one is hot like hell)

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by dirtybeagles » Fri Jun 10, 2016 6:29 am

Cannikin wrote:Nope, any 5V connection on the control board is the same 5V so you only need to hook up one.

I actually did end up coming OUT of the 5V GPIO on the Pi and it works great!
Question on this. Do I have to do anything special is I connect the 5v and GND from the VGA to the pi0? I am having some strange issues with the VGA connected to the powerboost with flickering on the screen. I am thinking it may have something to do with my amp (still waiting on the adafruit one, because I think my current amp is using to much amperage).

I assume you just take 5v and GND and solder those wires to the pi0? Thats it? I do not have to run another GND wire from the PI0 to the powerboost?
Last edited by dirtybeagles on Fri Jun 10, 2016 6:31 am, edited 1 time in total.

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Re: Full VGA resolution (640x480) 3.5" display, composite in

Post by dirtybeagles » Fri Jun 10, 2016 6:31 am

Mad_Duke wrote:Which display? Please :) I'm ordering mine tomorrow (because present one is hot like hell)
The same one Cannikin got. It is from China so it takes about a week or more to get it. I think it took a whole 5 days for mine to arrive.

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