I designed all the 3d printed components in Fusion 360. With the touch screen in hand I was able to use its dimensions to create a mock up of the entire build. I found a Pi4 model on GrabCad and was accurately able to plan this whole project out.
I printed the body of the radio that would hold the screen in ASA filament at 10% infill. The body and Pi4 are attached to existing screws on the screen structure.
If you would like to print this body for a project of your own, the stl can be found on
The build consists of the following components.:
- Raspberry Pi4 4GB
- 8GB Micro SD Card
- Waveshare 7.9 Touch Screen
- 12 to 5vt Voltage Step Down Converter
- 3.5mm Audio Cable Ground Loop Isolator
- USB Audio Sound Card
- USB Video Card
- 6ft USB Extension Cable
- 4 Port USB Hub
Software
There is a bit of a learning curve with this software.. To Customize it. Otherwise in default settings, it works straight outa the gate. Issues I encountered:- The screen wasn’t showing the entire UI, This involved finding a file in the Raspberry Pi and changing a setting.
- Next came power failures, after connecting a reverse camera and turning it on, Id get low voltage warning and frequently the pi would shutdown and reboot.
- I then had the issue of the SDCard getting corrupted when disconnecting power.
1. This fix was easy but complicated if your not familiar with Pi operating system. The process was to go to close OAP (Openauto-pro), and instead of choosing shutdown, push back. This then minimizes OAP and shows the Rasbperry pi desktop. From here i found the folders icon, and then browsed the folders to find: openauto_system.ini.
Location: /home/pi/.openauto/config/openauto_system.ini
Open that file, then Find the heading: ScreenType=0
Then change that 0 to a 1 and save. (1 = Widescreen)
2. This was a result of the video capture card taking to much power when the camera was on, and the solution was to swap from a 5v 3amp power inverter, to a 5vt 10 amp power inverter.
3. This was result of the SDCard having read/write capability. The card would get corrupted if something was being written while power was disconnected. The fix was to lock the SDCard to Read Only.
