Hi!
So, I received my screen (very quickly in fact, I didn't take the time to write a feedback earlier, sorry)
Some photos:
So it's pretty thick because of the touch panel and the glass screen. BUT, it's exactly the same frame than those composite screens.
So I remove all the frame (it's just clipped with the white plastic part of the screen)
(You can see the inside of the touch panel on the right.)
So now I can swap them and have a DPI screen without touch panel to save some room on this build.
And save the touch screen with the old composite screen for another project (not sure it will works but i'm quite confident that I just have to connect the touch screen connector to GPIO (I2c)
![Image](https://i.ibb.co/5TpmL5R/out2.jpg)
DPI screen without touch panel on the left, composite screen with touch screen on the right.
![Image](https://i.ibb.co/K6V0WY4/20211020-163623-HDR.jpg)
Almost thin!
So yeah, unless your RPi is perfectly aligned with the connector in your build (which is possible I think), you'll need some ribon to connect everything.
I tried those two:
https://fr.aliexpress.com/item/33030523 ... 6c37JnRXMF
https://fr.aliexpress.com/item/33020373 ... 6c37JnRXMF
Wasn't sure about the sufficient strength of the small one but it appears that this is ok (and the big on is a little too big)
Everything fits!
I have to put the connector upside down and do some modification as you can see, because I plugged it in the bottom side of my RPi. I didn't have the choice but it should be easier if you solder it the right side...
Make it works (RPi 4):
So the screen is plug and play, but not with Retropie....
Waveshare give a good wiki to help with the screen:
https://www.waveshare.com/wiki/3.5inch_DPI_LCD
I try to follow that but I have nothing on screen.
I just have to comment
Code: Select all
dtoverlay=waveshare-35dpi-3b-4b
dtoverlay=waveshare-35dpi-3b
Seems pretty logical because I don't use a RPi3, but nothing is explain...
So if I remember well, it works like that but:
In config.txt file, you have this line (again RPi 4 only, didn't test with other):
Which enable 3D acceleration but made many command from config.txt obsolete. (like "display_rotate")
So the wiki told you to comment this line
Note: For Raspberry Pi 4, you need to comment out dtoverlay=vc4-fkms-V3D.
Which is supposed to make the screen work (and it does). But retropie can't run without vc4-fkms-v3d...
So you have to leave it and that why you have to make some change in the config.txt file.
To make "display_rotate=1" work, you have to modify cmdline.txt, see here:
https://forums.raspberrypi.com/viewtopic.php?t=247619
Now, for me the screen was almost ok, just some bad "flickering"/bad display.
This came from this line:
Code: Select all
hdmi_timings=640 0 20 10 10 480 0 10 5 5 0 0 0 60 0 60000000 1
I don't understand all the parameters in this line (and didn't try for now).
First I suspect that it should be dpi_timings instead of hdmi_timings...
And I finally just comment it to get rid of any display flickering, so yeah, I suppose there is a mistake here
And the resolution?
It's.... perfect!!
I can finally play n64 games with the original image!
I undo all the modifications I had to do to make the composite screen legible (enlarge retropie font, bigger terminal,...)
All is now in default size (the terminal too) and it's very clear
Sorry, it's hard to pay homage to a screen in photos.
![Image](https://i.ibb.co/M1sK6zr/18-01-20.png)
This is the original font size!
Hope it will help!
EDIT:
This is my config.txt:
Code: Select all
[all]
dtoverlay=vc4-fkms-v3d
disable_splash=1
gpio=0-9=a2
gpio=12-17=a2
gpio=20-25=a2
dtoverlay=dpi18
enable_dpi_lcd=1
display_default_lcd=1
extra_transpose_buffer=2
dpi_group=2
dpi_mode=87
dpi_output_format=0x6f006
#dpi_timings=640 0 20 10 10 480 0 10 5 5 0 0 0 60 0 60000000 1
#dtoverlay=waveshare-35dpi-3b-4b
#dtoverlay=waveshare-35dpi-3b
#dtoverlay=waveshare-35dpi-4b
#display_rotate=2
disable_touchscreen=1
So I visibly comment
too... don't remember why.
If someone is comfortable with this file, don't hesitate to give your feedback