Hello,
I’m trying to connect the raspberry with react image to an Audi RNsE radio, I’m testing with a normal screen, when I connect to the radio, I can’t get an image, how can I change the image settings? Does anyone know the correct definition in config.txt
Hi @MrDude,
I’m about to start on a project to do the same thing - connecting the Raspberry Pi to my RNS-E to get CarPlay up and running. How are you connecting the output from the Pi to the RNS-E? There are two main options that I am aware of:
Are you using one of these options or something else?
I believe the correct video output format would be 576i PAL, which in the RPi config.txt should be something like:
hdmi_group=1
hdmi_mode=22
I hope that helps!
Hello Polo,
thanks in advance for the answer, I’m using option 2, I’m using an active combiner with the 5v coming from the VGA, then connecting the RNsE’s 32 pin plug to the pins for this purpose…
so I’m going to try this configuration.
Hi @MrDude,
I haven’t got this far with my build yet - I’m still collecting parts! I was planning to build my own sync converter to use, but the one you have looks good! Where did you get it?
What resolution options have you tried so far? I know this has been made to work by others with a sync combiner, so I’m sure it’s possible. Here’s a post from a thread on the TTForum that you might have seen where the initial boot screen works, but then the Raspian desktop automatically changes the display resolution to one the RNS-E can’t display.
Have you tried connecting to the Pi through VNC once it’s booted up? That should give you an idea as to what resolution it thinks it’s running.
Let me know how you get on - I’m planning on starting this in the next few weeks - initially with my old 192 RNS-E and then when that works I’ll give the 193 a go…
Hi, @Polo
I didn’t know about this TTForum post yet… I’ll take a look. I already have mine working with OpenAuto Pro, but I would like to use this one from React 
about the synchronizer, I did some reading and understanding how vertical and horizontal polarity works and I ended up building this PCB, if you need it, I can provide you with one I have several of these.
If you prefer, you can add me on Telegram
@MrDude what issue are you getting exactly with react-CarPlay? Are you getting no video display at all?
Hi, @rhys_m
yes, no image signal is passing, only sound passes, but I think it is a change in the image configuration, as I am connecting it to an image combiner with vertical and horizontal polarity for synchronization, as this is the only way the image signal is received by radio RNs E
Do you know what the best configuration might be?
Thanks
Hi @MrDude,
What is your current config.txt setup for this? What values are you using for hdmi_group and hdmi_mode?
Hi @MrDude - have you had any luck?
I’ve finally had a chance to try this out on both the 192 RNS-E and the 193 RNS-E using a pi 3B+ running Buster (i.e. not the latest OS). I’ve built a circuit to do the sync which should work the same way as the one you are using.
Results so far: I’ve got both the 192 and 193 working with hdmi_mode=7. The 193 also works with hdmi_mode=22, although the image is flickering a bit - I’m guessing it’s due to how the interlacing is handled.
Some pics:
192 @ 480i:
193 @ 480i:
193@576i:
A long way to go before it’s ready to go in the car, but it’s progress!
Super cool 
love it
@rhys_m - thanks! Next job is to get into your code and control the interface using the buttons on the head unit and steering wheel (via canbus). I’ve also got a patch planned to convert the video stream back to 16:9, as currently the Pi thinks it’s running 4:3, hence the stretched icons and text…
Hello Polo,
I haven’t had the opportunity to do more testing again yet. but yes I use a Sync Combiner that I send here in a photo. So from what I understand for 193 we just have to put hdmi_mode=22? will this be it?
how did you put overscan?
Hi @MrDude - I think the circuit I have is pretty much identical, including the values of the capacitors and resistors…
The one thing I have found through reading online is that the most recent Raspberry Pi OS versions use a different graphics driver which might not be as easy to configure with these PAL / NTSC resolutions. I’m using the version of the OS that I had already installed a few years ago on my 3B+, so it definitely works with the different hdmi_mode values.
Have you tried using VNC to connect to your pi once it’s running? That should give you an idea as to what resolution it’s actually using.
I only started looking at overscan once I had the screen working - I needed to do a lot of tweaks to get the image on the screen fully. Without that, the display worked, but was cut off on the left and bottom
Hi, @Polo did you make any further progress? I had to stop this time because my car engine died and I had to replace it. I will now go back to that
Hi @MrDude - not managed to do much more yet. Current challenge is getting the latest code to run cleanly on an up to date Raspberry Pi OS with the Pi 3B+ I have. I noticed that the most recent version of the React CarPlay code was running very slowly on the latest OS, so not sure what’s changed since the version I was using (which I think was probably React CarPlay 3.x). Alternatively I need to switch to my Pi 5, but I’ve heard it can be a problem to get it to output the correct video modes, although that might have been fixed with the most recent version of the OS.
Once I get past the issue of finding a way to build and run the code on the Pi, I’ll work on picking up the canbus data for the control buttons and knobs, as well as the patch I’ve already tested on a separate linux machine for getting the display to resize for 16:9. Once those basics are covered, I think it will be back to the hardware installation - I need to work out how to shutdown and startup the pi cleanly, which will probably require some more electronics…
Hopefully I’ll get some time to work on these things during November!
Hi Polo, I managed to run react-carplay with the same sync combiner that you have. (Thanks @MrDude).
I am using PI 4B, with the latest os, with a custom EDID file for the HDMI output. (480i), but I get this image on the navigation.
This is what gets send via HDMI output: Crtc 3 (101) 720x480@60.00 27.027 720/16/62/60/- 480/9/6/30/- 60 (60.00) D 4:3
Any thoughts? I have a PI 3B+ as well, but I would like to dig to make it work on the latest Pi OS
Hi @Quasar ,
Good work! I think I saw a similar result when the Pi was outputting progressive instead of interlaced video. I’ve recently tried using a Pi 5 with a custom EDID, but no luck whatsoever with any kind of output.
Would you be able to share your EDID here? I can take a look and compare it to what I have tried with my Pi5.
On a separate note, I’ve also modified the code a bit to process the RNS-E’s button presses. I’m planning on recording a video to show how it works, and will share when done.
Between us, we’ll get this working!
Polo, this is the EDID I’m using: https://fastupload.io/0012e5d278166a18
Also, if I change the resolution directly from the PI for the HDMI to be 720x480, I get the same result.
I can help with anything related to coding, but need to figure a way to output the correct image on the RNS-E first.
Maybe we share ideas and do a ‘hackaton’ to get things done.
Let me know!
