Screen performance?

[Fin-Glim]

You could try forcing the frame buffer to the resolution of the screen. What I have found is that quite a few of the 3.5" composite screens are not actually 320 x 240 - they are a little under - for example the ones I have are actually 320 x 234.

To set the frame buffer open up /boot/config.txt and uncomment/modify the following lines to match your screen resolution.

Code: Select all

framebuffer_width=320
framebuffer_height=234

Could you provide more specific instruction on how to make this modification?
Please & thanks, Gretchen

[Sushi]

You could try forcing the frame buffer to the resolution of the screen. What I have found is that quite a few of the 3.5" composite screens are not actually 320 x 240 - they are a little under - for example the ones I have are actually 320 x 234.

To set the frame buffer open up /boot/config.txt and uncomment/modify the following lines to match your screen resolution.

Code: Select all

framebuffer_width=320
framebuffer_height=234

Could you provide more specific instruction on how to make this modification?
Please & thanks, Gretchen

There are two ways:

Put the Pi's SD card into your computer and find a file called config.txt. From there, just add the two lines provided above to the bottom and save.

The second way starts by accessing the terminal on the pi. Then, type "sudo nano /boot/config.txt". This will open up a text editor. Then, just add the same lines provided above to the bottom. Press CTRL+O and then enter to write to the file. Press CTRL+X to exit. Then, reboot the pi.

[Lphillimore]

Stickied.

[bakub]

Hello,

i have got the same problem with my screen like a author this topic, my screen is a fuzzy.

I use screen 3.5 lcd from gearbest:

https://www.gearbest.com/development-bo ... 29447.html





Could someone help me or give me some tips?

Thanks.

[bakub]

When i set in /boot/config.txt

sdtv_mode=2

it repair menu , but now game is not smoothly.

How change retroarch to video PAL ?

[BlastoSupreme]

I had the same problem.what i did to fix it; Ground to the pi, Ive used a composite (rca) single shielded wire from vid1 and ground from lcd driver board to the pi tv out and the ground next to the tv out on the pi. Screen is perfect now with no fuzzy lines, just crisp. Good luck

i can second that....

i went back and changed the wiring after my build was finished (my son complained that the screen was having intermitten interference)


used an old rca lead lying around




your board may vary but the principle is the same





now the screen is crisp (as can be expected) and no interference

I’m having the same issue. You’re using the negative for ground? I’m sorry if that’s a stupid question. I’m very new to electronics.

[Helder]

Negative always goes to Ground in just about any circuit.

[DeadSeeLife]

Ok so I’m having the same issue as the OP. I’m getting like a weird “interference”-like noise at the top of the screen. I followed the directions and used an old RCA cable but I’m not positive that I’m hooking everything up to the right spots. I’m using the backup camera screen from amazon and I have variant 7. So the board is practically glued to the back of the lcd. As long as the colors of the wires don’t change from one variant to the next then I think everything is in the right spot. But it still doesn’t look that great. I can’t seem to get a photo of the noise I’m seeing. Still trying. Here’s how I have it hooked up.

[DeadSeeLife]

Ok. So when I start it up...it says AV2 on the screen. Do I have the video signal going into the wrong input? I used wermy’s first video as an example but he was using the adafruit screen. Also...here’s what the noise kind of looks like.
Top right corner.

[DeadSeeLife]

Ok redid everything. Still the same. Took off the white AV2 wire.
Now going from pi OUT to AV1 using the inside part of an rca cable. The ground i think is grounded on the lcd and the pi. Power to power.
Still have the noise.