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LCD kernel module notes

2

How can I undo the sudo code that was run with the wrong type of LCD “…-show” The system boots to a certain point and then just does not continue. Ive tried mounting the micro sd and see if I can change to the designated screen, but can’t find where or how without formatting the drive and reinstalling the system The code that was used was:

sudo rm -rf LCD-show 
git clone https://github.com/goodtft/LCD-show.git 
chmod -R 755 LCD-show 
cd LCD-show/
sudo ./LCD35-show

but should have been:

git clone https://github.com/goodtft/LCD-show.git
chmod -R 755 LCD-show
cd LCD-show/
sudo ./MPI3508-show

https://trickiknow.com/raspberry-pi-3-complete-tutorial-2018-lets-get-started/

 New contributor
  • You may try reformatting the SD Card and burning a fresh version of Raspbian, if you don’t want to buy another card. – user96931 yesterday

2 Answers

2

Question

Rpi can no longer boot after installing wrong LCD driver. How to fix?

Answer

Short answer

A quick and dirty fix is:

  1. Use a new SD card with a freshly downloaded Raspbian image, without any new LCD driver installed.
  2. Then install your correct LCD driver.

Long answer

You can fiddle with the Raspbian config files to remove wrongly installed the LCD driver, but that is very messy. You might might to read the references below to see how tricky it is.

/ to continue, …

References

Banngood Geekcreit 3.5″ 320 X 480 TFT Touch LCD For Rpi

Banngood Geekcreit 3.5″ 320 X 480 TFT Touch LCD Manual and Driver

TrickShow Rpi3 Complete Tutorial 2018 – 2018jan31

YouTube TrickShow Rpi 3.5″ Touch LCD + LiPo Power Bank

How to install ILI9341 LCD Kernel Module Part 1

How to install ILI9341 LCD Kernel Module Part 2

0

I assume you are running Raspbian Stretch. If so you can use systemd to try to boot into rescue or emergency mode. In systemd.special — Special systemd units you will find for

rescue.target

A special target unit that pulls in the base system (including system mounts) and spawns a rescue shell. Isolate to this target in order to administer the system in single-user mode with all file systems mounted but with no services running, except for the most basic. Compare with emergency.target, which is much more reduced and does not provide the file systems or most basic services.
[..]
Use the “systemd.unit=rescue.target” kernel command line option to boot into this mode.

So pull out the SD Card of the RasPi, make a backup image from it on another computer and then edit cmdline.txt on the boot partition. Just append systemd.unit=rescue.target at the end of the line and boot it in your RasPi.

You can also try to boot with systemd.unit=emergency.target in cmdline.txt but as explained in systemd.special that’s much more limited in execution of programs.

With some luck you may be able to fix your problem.

  • thanks for the help – user103985 6 hours ago
  • @user103985 Glad to help you 🙂 Could you fix your problem? If so it would be nice if you could accept the answer by ticking the check on the left side. This will finish the question and show other users that it has a solution. – Ingo 6 hours ago
  • Haven’t tested just yet, but will in a bit. – user103985 5 hours ago

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