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

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

Post by Mad_Duke » Fri Jun 10, 2016 10:27 am

dirtybeagles wrote:
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?
Yep. Just connect the 5V from GPIO if the powerboost is giving you headaches. Have in mind that connecting to the Pi you will also see the low power rainbow rectangle if it draws too much power (undervolt). I did it because of that because my display (current) is really really hot (so It probably draws too much power and looses it on heat).

Plus, you only need one ground so you can choose if it will go through the composite side or directly from the GPIO. So that way (if it's on the video cable) you can example have an external composite also (if you don't want or can't have an HDMI out) and have the signal on a simple switch. (for connecting to an older TV which doesn't have HDMI).

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

Post by dirtybeagles » Sat Jun 11, 2016 4:00 pm

[mention]cannikin[/mention]

One thing I am not seeing here is how are you going to mount the bracket for the top screws?

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

Post by Ganreizu » Sat Jun 11, 2016 4:40 pm

dirtybeagles wrote:[mention]cannikin[/mention]

One thing I am not seeing here is how are you going to mount the bracket for the top screws?
Short answer: You don't.

Long answer: You can mount screw posts i think close to the top holes on the board but it will only secure the board, not connect the front case to the back case. On the 3D printing forum wermy is thinking up a way to make a 3D printed latch that will secure above the board but within the shell to attach both halves of the case. Probably only a problem specific to us so it's extremely appreciated that he would do this for us.

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

Post by Cannikin » Sat Jun 11, 2016 5:12 pm

dirtybeagles wrote:[mention]cannikin[/mention]

One thing I am not seeing here is how are you going to mount the bracket for the top screws?
Check out my build page to see the hook system I came up with to replace the screw posts.

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

Post by marcushg » Tue Jun 14, 2016 5:18 am

Sorry, first posted this on alternate displays thread:

Ok, I just got this one today through mail. It's the ebay one 640x480 3,5" display
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Any ideas on how to wire this one? i see there's no 12v input! so it should work with just the 5v points? or should i use the 3.3v also?
now ive read all this thread, which is the best way to power it? from the powerboost? from the pi?

but is there a good possibility on using vga without loosing the hdmi out? i read about those gert666 adapters but don't know if it fits with our pi zero project... https://www.raspberrypi.org/forums/view ... 94424&f=91
anyone tried? or should i forget about and use composite?
best way to mount it? ribbon at the top with monitor rotation through its menu?

Just wanted to know the best way to do it now you have the experience
Thanks!!!!

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

Post by Mad_Duke » Tue Jun 14, 2016 8:00 am

Using GERT you don't loose the HDMI, but you get shitty colors. It's not "full fledged VGA".

Cheap and small linux workable VGA out USB display adapters don't exist (pitty because it should work with resolutions around 640x480, 800x600x)

Oh well.. :( I would also like to use VGA but it's a no go :(

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

Post by Cannikin » Tue Jun 14, 2016 10:03 am

marcushg wrote:Any ideas on how to wire this one? i see there's no 12v input! so it should work with just the 5v points? or should i use the 3.3v also? Now ive read all this thread, which is the best way to power it? from the powerboost? from the pi?
Yep it's already 5V so you connect it directly to the PowerBoost or from one of the 5V GPIO pins on the Pi (this is what I ended up doing).

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

Post by marcushg » Tue Jun 14, 2016 1:03 pm

is there any difference between wiring jut one 5v point or two?
Cannikin, i wrote in your gbz build thread
thanks

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

Post by marcushg » Wed Jun 15, 2016 5:35 am

I'm copying this from my build log as it's screen related, need advice:

Ok, next steps, changed the screen for 640x480 one as i wasn't satisfied with the normal screen.. wired power from powerboost to pp points at the rpi zero and from gpio to the screen. wired the yellow composite cable from the screen to the rpi0 and ... it works! is the ground point from the screen (next to the composite one, not the power one) to the rpi?

the thing is that when emulation station (retropie) has booted and i'm in the menu for choosing games the screen seems to lose signal and gets completely black! any idea? I think I also have to adjust the screen resolution and the overscan as the screen looks way off!
need some advice!

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

Post by Fleder » Wed Jun 15, 2016 5:47 am

marcushg wrote:the thing is that when emulation station (retropie) has booted and i'm in the menu for choosing games the screen seems to lose signal and gets completely black! any idea? I think I also have to adjust the screen resolution and the overscan as the screen looks way off!
need some advice!
Are you talking about getting no video signal once you start a rom or even before that, still in the rom selection screen?

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