Changing the screen resolution

The Yodeck Playbox (based on Raspberry Pi) automatically detects on start-up the "preferred" resolution of the connected monitor (usually, its native resolution). Some times, the resolution might not be detected properly. This might happen if you power up your Playbox without a screen connected, or if after a power failure the Playbox starts before the screen has the time to power up and report properly. In this case, the standard VGA resolution of 640x480 is used.

Try rebooting your Playbox, it might be just fine. If you are having issues with the resolution, you can manually set the resolution for your screen.
  • Go to "Monitors" list and edit the monitor in question.
  • Click on the "Advanced" tab.
  • Make sure the "Allow Raspberry config.txt Override" toggle is set to "ON".
  • In the "Raspberry config.txt Override Directives" textarea, you will have to enter two advanced parameters hdmi_group, and hdmi_mode. These are detailed below.
  • After you are finished, click the "Save" button.
  • The Player will reboot. If you can't see anything for 5' (not even the Yodeck startup logo), then you should try a different resolution. You can also set the "Allow Raspberry config.txt Override" toggle to "OFF" to disable all extra settings and boot normally.
The "hdmi_group", and "hdmi_mode" parameters should be entered in one line each, followed by an "equals" sign, and then the desired value. For example, for 1080p at 50Hz, that would be:

hdmi_group=1
hdmi_mode=31

If you are using a standard TV screen, then you probably need to use CEA resolutions, and you should use hdmi_group=1 . If you are using a computer monitor, you probably need to use DMT resolutions, and you should use hdmi_group=2 .

Here are some commonly used hdmi_mode values for Full-HD and HD-Ready TV screens (remember, hdmi_group=1) :
PARAMETER      Resolution   Refresh Rate

hdmi_mode=4    720p          60 Hz
hdmi_mode=19 720p 50 Hz
hdmi_mode=41 720p 100 Hz
hdmi_mode=47 720p 120 Hz

hdmi_mode=5   1080i 60 Hz
hdmi_mode=20 1080i 50 Hz
hdmi_mode=39 1080i 50 Hz (reduced blanking)
hdmi_mode=40 1080i 100 Hz
hdmi_mode=46 1080i 120 Hz

hdmi_mode=32 1080p 24 Hz
hdmi_mode=33 1080p 25 Hz
hdmi_mode=34 1080p 30 Hz
hdmi_mode=31 1080p 50 Hz
hdmi_mode=16 1080p 60 Hz

Here are some commonly used hdmi_mode values for Full-HD and HD-Ready computer monitors (remember, hdmi_group=2) :  
PARAMETER      Resolution   Refresh Rate

hdmi_mode=82 1080p     60 Hz
hdmi_mode=85 720p     60 Hz
You can find more valid resolutions here.

Defining a Custom Resolution


To define a different or custom resolution, you can use Coordinated Video Timings. Here is the template to be used in the "Raspberry config.txt Override Directives" textarea (make sure that you have read this whole article first):

hdmi_group=2
hdmi_mode=87
hdmi_cvt=<width> <height> <framerate> <aspect> <margins> <interlace> <rb>

where as:
width        width in pixels
height     height in pixels
framerate   framerate in Hz
aspect     aspect ratio 1=4:3, 2=14:9, 3=16:9, 4=5:4, 5=16:10, 6=15:9
margins     0=margins disabled, 1=margins enabled
interlace   0=progressive, 1=interlaced
rb         0=normal, 1=reduced blanking

Using a 4K (3840x2160) Screen


To use a 4K resolution (dubbed UHD, Ultra-High Definition or Ultra-HD) of 3840x2160, you can use a special set of parameters in the "Raspberry config.txt Override Directives" textarea. Make sure that you have read this whole article first.

WARNINGS (PLEASE READ CAREFULLY):

  • This resolution has been tested to work on two different 4K Samsung TVs. No other tests have been made.
  • We do not yet support running production-grade Yodeck deployments in 4K.
  • 4K Video playback is not supported. All uploaded videos will be downsized to 1080p. Only images and web pages will be rendered at 4K.
  • Using a 4K resolution will make your Player a bit slower.
  • 4K will probably work only on a Raspberry Pi 2 or Raspberry Pi 3. (Note: if you have a Playbox, it is either a Pi 2 or 3, depending on when you purchased it)
  • Extra GPU memory is required, so you might be restricted to the number of Playlists/Media/Widgets you can add to a Show.
  • A future update in Yodeck software may break 4K support. You should not be using 4K resolution without first contact our Tech support.
  • If you are having trouble or you need help getting 4K to work, we would be glad to help out, just contact us.
  • It is very very very unlikely that the settings presented here will damage you screen. But it might be possible, we really can't say for sure. So, make sure you understand the risks.

Configuration for 4K (3840x2160) Resolution


To get 4K resolution at 25Hz use the following set of parameters in the "Raspberry config.txt Override Directives" textarea:
gpu_mem_1024=256
framebuffer_width=3840
framebuffer_height=2160
max_framebuffer_width=3840
max_framebuffer_height=2160
hdmi_ignore_edid=0xa5000080 hdmi_drive=2
hdmi_pixel_freq_limit=400000000
hdmi_group=2
hdmi_mode=87
hdmi_timings=3840 1 48 32 80 2160 1 3 5 54 0 0 0 25 0 220430000 3
To get 4K resolution at 24Hz, replace the whole hdmi_timings line with this one:
hdmi_timings=3840 1 48 32 80 2160 1 3 5 54 0 0 0 24 0 211190000 3
To get 4K resolution at 28Hz, replace the whole hdmi_timings line with this one:
hdmi_timings=3840 1 48 32 80 2160 1 3 5 54 0 0 0 28 0 248140000 3
Unfortunately, we have not found a safe and stable way to get to 30Hz. You should probably use 25Hz which is the lighter and safer that the other two.


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