3.5" LCD for Raspberry Pi - No Luck

Question

Hi all,

Fairly new to Raspberry Pi / Linux / Electronics. Recently purchased a Raspberry Pi 3 B and have been having great fun with it.

Purchased this 3.5" display and am having no luck getting it to work.

Once I fit it onto the GPIO, it displays all white - good, it’s getting power.

I run curl -L http://coreelec.io/2q | bash as per the product description page - it downloads, unzips, and runs the contents of the package.

I first attempted this on a RetroPie install - it did nothing, video was still coming through HDMI.

Next I tried on a Raspbian install - it disabled the HDMI, but the LCD still just displayed all white. I was able to restore HDMI video using the LCD_hdmi script as per the product description page.

Finally, I created a fresh NOOBS microSD, installed Raspbian Lite, ran the curl command - same as with the Raspbian install. It seems to do what it’s supposed to, then it reboots, doesn’t output to HDMI, and the LCD never changes from solid white.

It may be worth mentioning that the screen I received doesn’t look exactly the same as the one pictured on the Core Electronics shop - I don’t know if that makes any difference or not. The one I received is pictured here:

Any help/suggestions would be greatly appreciated.

aerosol · Accepted Answer

Kedei do have a screen driver for RetroPie - but it's not for the screen that I have. It's for one that connects via HDMI instead of SPI.

In the end I managed to get everything working thanks to PiScreen Driver Install Instructions - ozzmaker.com and https://www.raspberrypi.org/forums/viewtopic.php?t=178443

Cheers everyone!

jomoenginer · Answer

It looks like you have posted on the seller's site but you have not received any replies. Also, considering that there is very little info on the screen, it might be a bit tough to get the screen working. However, you could look at the output of 'dmesg' to see if there are any driver related errors. Also, check and logs such as messages to see if there are any clues there. Look at a similar display and see if you can go through the install for that to find if there are any missing steps. This looks interesting: https://www.raspberrypi.org/forums/viewtopic.php?t=178443

shabaz · Answer

There could have been an error during execution, did you examine the entire output after the software downloaded and ran? There may be a chance of that if there is a need to be a root user, or if the software is quite old (the display looks like it was designed in the time of earlier Pi models). The information Jon links should help, particularly the fbi/fbdev related detail at that location.

One other thing that could be a high possibility, is lack of power (the Pi 3 with LCD will likely need the official Pi 3 power supply - not sure if you're using that or a different one).

beacon_dave · Answer

You could take a look at the script you are running for clues... Starts with looking to see if the archive already exists and if not downloads 'LCD_show_v6_1_3.tar.gz', extracts it and then executes 'LCD35_v' which is probably another script that you could take a look inside at its contents. #!/bin/bash
# This script will download and install the necessary files to 
# drive the 3.5" touch display.
VERSION="v6_1_3"
SOURCE="https://goo.gl/yZPq4p"
cd ~
# Check if drivers archive already exists
file="./LCD_show_$VERSION.tar.gz"
if [ -f "$file" ]
then
 echo "$file found."
else
 echo "$file not found - downloading"
 wget -O "LCD_show_$VERSION.tar.gz" $SOURCE
fi
# Check if archive is already extracted
directory="./LCD_show_$VERSION/"
if [ -d "$directory" ]
then
 echo already extracted
else
 echo extracting...
 tar -xvzf LCD_show_v6_1_3.tar.gz
fi
echo Beginning installation
cd $directory
./LCD35_v It is downloading the files from kedei.net and if you look there http://kedei.net/raspberry/raspberry.html you find a bit more including a screen driver for RetroPie.