Posts: 7
Joined: Sun Dec 21, 2014 12:38 am

3.5 Zoll Display not showing on RetroPie

Wed Apr 29, 2015 10:52 pm

Hallo ihr lieben,

I'm scratching my head for 3 days:

I'm trying to get work at RetroPie with my 3.5 inch touch screen display. But no sucess.
I've tried anything, like example adafruit tutorial: ... itft-setup

I've set on config.txt dtoverlay=pitft35r I hope this is correct.

or FBTFT at "Step-by-step using FBTFT"

The stupid:

Code: Select all

sudo modprobe fbtft_device name=adafruit22
I don't know which name the display has. So I can't continue this tutorial too. Is there any ways to get display name?

I've bought the display from:
It's work fine on preconfigured raspbian images:
But I want this working on RetroPie!

I hope you can help me. :)

- Chinafreak

Posts: 7
Joined: Sun Dec 21, 2014 12:38 am

Re: 3.5 Zoll Display not showing on RetroPie

Sat May 02, 2015 10:53 am


Now the display is showing RetroPie Interfaces / Emulator.
I've there a problem:

- I'm using Raspberry Pi 2
- display name: flexfb
- display:
- 3.5 inch display
- 480x320 resolution
- with touch screen (I don't need that, but it installed.)
- I'm using "fbcp &" for displaying RetroPie Emulation
- pre-configure raspbian image:
- or this file for your exists raspbian on raspberry pi:

v v v v a file to get work on display v v v v

Code: Select all

tar xvf LCD-show.tar.gz
cd LCD-show/
sudo ./LCD35-show
Short text problem:
- the display show me very glitch (wrong color etc.)
- display don't want rotate
- a bit slow.

Long text problem:
Problem 1
I got working on RetroPie with the display and it look good. But its laggy. So I've increase speed of the display on /etc/modules to "49000000" (default is 16000000), but then the display is just white. Then when I'm setting to "48000000-24000000" then the display show me glitch (but now it faster). At "16000000" show look fine, but it's very slooow. And fps ist set to 60.

Whats wrong? On my adafruit 2.8 display work fine on speed 80000000, but the display is a bit too small for me, so I've bought this one on 3.5 inch display.

Problem 2
Sadly I can't rotate the display, I've try change the value on /etc/modules "rotate=XX", but this was not working.

Problem 3
however, the display is not fast enought (~18fps). But it's still playable, but it would be nice, if the display is faster.

If you need more information, please just ask it.

- China


Code: Select all

# /etc/modules: kernel modules to load at boot time.
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
# Parameters can be specified after the module name.


flexfb  width=320  height=480  regwidth=16 init=-1,0xb0,0x0,-1,0x11,-2,250,-1,0x3A,0x55,-1,0xC2,0x44,-1,0xC5,0x00,0x00,0x00,0x00,-1,0xE0,0x0F,0x1F,0x1C,0x0C,0x0F,0x08,0x48,0x98,0x37,0x0A,0$
fbtft_device debug=3 rotate=90 name=flexfb speed=48000000 fps=60 gpios=reset:25,dc:24
ads7846_device model=7846 cs=1 gpio_pendown=17  keep_vref_on=1 swap_xy=1 pressure_max=255 x_plate_ohms=60 x_min=200 x_max=3900 y_min=200 y_max=3900


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# uncomment if hdmi display is not detected and composite is being output

# uncomment to force a specific HDMI mode (this will force VGA)

# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes

# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display

# uncomment for composite PAL

#uncomment to overclock the arm. 700 MHz is the default.

hdmi_cvt=480 320 60 1 0 0 0

I'd pay for solutions 15$ but I think this is not allowed. x)

Posts: 685
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 Zoll Display not showing on RetroPie

Sat May 02, 2015 6:13 pm

If you increase the speed and get glitches, wrong colors, white display (config trashed) you're running it too fast. There are many factors that determine how fast you can go. Many of these controllers are listed in their datsheet with a max speed of 10MHz, so we run them out of spec.
If you want reliable high speed 3.5", this is a good bet: ... 581-pi-ext

To get rotation working, you need to find the controller datasheet and locate the register that controls rotation. Then set that in your init sequence. The flexfb driver can only flip width/height, not rotate the display hardware.

Posts: 1
Joined: Wed Jul 27, 2016 12:18 pm

Re: 3.5 Zoll Display not showing on RetroPie

Wed Jul 27, 2016 12:23 pm

I have a different issue. I can install everything but when I try to launch startx it returns no monitor is detected.
Now, the lcd works good. I can change the font size but I can't rotate the image, fair enough.
But... if you look inside LCD35-show......

Code: Select all

sudo mkdir /etc/X11/xorg.conf.d
sudo cp ./waveshare35a-overlay.dtb /boot/overlays/
sudo cp -rf ./etc/X11/xorg.conf.d/99-calibration.conf-35  /etc/X11/xorg.conf.d/99-calibration.conf
sudo cp -rf ./usr/share/X11/xorg.conf.d/99-fbturbo.conf  /usr/share/X11/xorg.conf.d/
sudo cp ./cmdline.txt /boot/
sudo cp ./inittab /etc/
sudo cp ./boot/config-35.txt /boot/config.txt
sudo reboot
sudo cp ./inittab /etc/ ??????? inittab isn't no more aviable in raspian jessie?
could be this the problem? i assume it is replaced with systemd, but how can i edit it in the right way?

Many thanks!

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