While we do not officially support Composite/RCA (and strongly encourage you to use HDMI if possible), it is technically possible to use it using an adapter like this.
To do so, you need to jump through a few hoops:
- Flash out the latest disk image to a new SD Card.
- Mount the SD card in your computer and make the following changes to config.txt on the boot partition:
- Change the line "hdmi_force_hotplug=1" to "#hdmi_force_hotplug=1".
- Append the line "sdtv_mode=0" (for PAL) (see this page for details).
- Connect your Composite/RCA cable.
- Unmount the SD card, insert it into your Raspberry Pi and boot it up.
- You should now get the PIN code on your screen and be able to pair the device.
Once you have paired your device, the device will reboot and you will lose the settings above (because Screenly manages them for you). As such, you need to make some changes to the screen.
Navigate to the screen you just paired in the management interface. Go to Manage, and Advanced. Then you need to set "Video Output" to Composite/RCA.
Lastly, you need to power down your Raspberry Pi and make a re-apply the "#hdmi_force_hotplug=1" setting to config.txt.
After this, you should be able to use your Raspberry Pi with Composite/RCA. Be aware however that if you do make any change on the advance section, the hdmi_force_hotplug setting will be reverted.
Please note that some Composite/RCA cables are labeled incorrectly for the Raspberry Pi. As such, it may not be the yellow cable (which normally denotes video) that receives the video signal. Thus you may need to test a different cable.