Guybrush
Posts: 1
Joined: Sun Aug 06, 2017 6:04 am

Re: STICKY: Setting up HDMI output when video output is wrong.

Sun Aug 06, 2017 6:27 am

Hi folks,

I'm new here and I'm having an issue setting up an LCD panel properly.

More specifically, this one:

http://www.ebay.com/itm/9-TFT-LCD-Displ ... 2749.l2649

I'm wondering if anyone here has experience with that specific screen. The driver board is PCB800099-V9. The panel is stamped BCL900-23EM. I cannot find any information or specs on it.

The issue: the panel is supposed to be 1024x600 (and that isn't really 16/9 either), but even after defining a custom setting in config.txt for it, the display is pretty horrid. In a web browser, fonts are pretty bad, fuzzy, pixels running into adjacent ones, irregular spaces...pretty much looking like bad scaling.

After spending a lot of time fiddling with it, it seems that using a resolution of 800x480 fixes the problem mentioned above. It's still not a pretty screen (TN panel, bad colors, bad angles), but the text looks correct, and pixel spacing is regular.

So I'm wondering if this is simply a 800x480 panel, or if my 1024x600 config is wrong (and if the driver board could have anything to do with the issue), because it basically looks like the higher resolution is being scaled down.

Here is the EDID output. It seems to be guessing that the resolution is 800x480. I just don't know how much of this is accurate.

Thanks a bunch for any ideas :)

Code: Select all

HDMI:EDID version 1.3, 1 extensions, screen size 47x26 cm
HDMI:EDID features - videodef 0x81 !standby !suspend active off; colour encoding:RGB444|YCbCr444|YCbCr422; sRGB is default colourspace; preferred format is native; does not support GTF
HDMI:EDID found monitor S/N descriptor tag 0xff
HDMI:EDID found monitor range descriptor tag 0xfd
HDMI:EDID monitor range offsets: V min=0, V max=0, H min=0, H max=0
HDMI:EDID monitor range: vertical is 56-75 Hz, horizontal is 30-83 kHz, max pixel clock is 210 MHz
HDMI:EDID monitor range does not support GTF
HDMI:EDID found monitor name descriptor tag 0xfc
HDMI:EDID monitor name is HDMI
HDMI:EDID failed to find a matching detail format for 800x480p hfp:44 hs:88 hbp:124 vfp:3 vs:6 vbp:46 pixel clock:33 MHz
HDMI:EDID calculated refresh rate is 60 Hz
HDMI:EDID guessing the format to be 800x480p @60 Hz
HDMI:EDID found unknown detail timing format: 800x480p hfp:44 hs:88 hbp:124 vfp:3 vs:6 vbp:46 pixel clock:33 MHz
HDMI:EDID established timing I/II bytes are AF EF 00
HDMI:EDID found DMT format: code 4, 640x480p @ 60 Hz in established timing I/II
HDMI:EDID found DMT format: code 5, 640x480p @ 72 Hz in established timing I/II
HDMI:EDID found DMT format: code 6, 640x480p @ 75 Hz in established timing I/II
HDMI:EDID found DMT format: code 8, 800x600p @ 56 Hz in established timing I/II
HDMI:EDID found DMT format: code 9, 800x600p @ 60 Hz in established timing I/II
HDMI:EDID found DMT format: code 10, 800x600p @ 72 Hz in established timing I/II
HDMI:EDID found DMT format: code 11, 800x600p @ 75 Hz in established timing I/II
HDMI:EDID found DMT format: code 16, 1024x768p @ 60 Hz in established timing I/II
HDMI:EDID found DMT format: code 17, 1024x768p @ 70 Hz in established timing I/II
HDMI:EDID found DMT format: code 18, 1024x768p @ 75 Hz in established timing I/II
HDMI:EDID found DMT format: code 36, 1280x1024p @ 75 Hz in established timing I/II
HDMI:EDID standard timings block x 8: 0x0101 0101 0101 0101 0101 0101 0101 0101 
HDMI:EDID parsing v3 CEA extension 0
HDMI:EDID monitor support - underscan IT formats:no, basic audio:yes, yuv444:yes, yuv422:yes, #native DTD:1
HDMI:EDID found preferred CEA detail timing format: 720x576p @ 50 Hz (17)
HDMI:EDID found CEA detail timing format: 1920x1080i @ 60 Hz (5)
HDMI:EDID found CEA detail timing format: 1920x1080i @ 50 Hz (20)
HDMI:EDID found CEA detail timing format: 1280x720p @ 50 Hz (19)
HDMI:EDID found CEA detail timing format: 1920x1080p @ 50 Hz (31)
HDMI:EDID found CEA format: code 6, 1440x480i @ 60Hz 
HDMI:EDID found CEA format: code 7, 1440x480i @ 60Hz 
HDMI:EDID found CEA format: code 2, 720x480p @ 60Hz 
HDMI:EDID found CEA format: code 3, 720x480p @ 60Hz 
HDMI:EDID found CEA format: code 21, 1440x576i @ 50Hz 
HDMI:EDID found CEA format: code 22, 1440x576i @ 50Hz (native)
HDMI:EDID found CEA format: code 17, 720x576p @ 50Hz 
HDMI:EDID found CEA format: code 18, 720x576p @ 50Hz 
HDMI:EDID found CEA format: code 19, 1280x720p @ 50Hz 
HDMI:EDID found CEA format: code 4, 1280x720p @ 60Hz 
HDMI:EDID found CEA format: code 20, 1920x1080i @ 50Hz 
HDMI:EDID found CEA format: code 5, 1920x1080i @ 60Hz 
HDMI:EDID found CEA format: code 31, 1920x1080p @ 50Hz 
HDMI:EDID found CEA format: code 16, 1920x1080p @ 60Hz (native)
HDMI:EDID found audio format 2 channels PCM, sample rate: 32|44|48 kHz, sample size: 16|20|24 bits
HDMI:EDID found HDMI VSDB length 5
HDMI:EDID HDMI VSDB has physical address 1.0.0.0
HDMI:EDID HDMI VSDB has no extension fields
HDMI:EDID adding mandatory support for CEA (1) 640x480p @ 60Hz
HDMI:EDID filtering formats with pixel clock > 162 MHz or h. blanking > 1023
HDMI:EDID best score mode initialised to CEA (1) 640x480p @ 60 Hz with pixel clock 25 MHz (score 0)
HDMI:EDID best score mode is now CEA (1) 640x480p @ 60 Hz with pixel clock 25 MHz (score 61864)
HDMI:EDID best score mode is now CEA (2) 720x480p @ 60 Hz with pixel clock 27 MHz (score 66472)
HDMI:EDID CEA mode (3) 720x480p @ 60 Hz with pixel clock 27 MHz has a score of 66472
HDMI:EDID best score mode is now CEA (4) 1280x720p @ 60 Hz with pixel clock 74 MHz (score 135592)
HDMI:EDID DMT mode (4) 640x480p @ 60 Hz with pixel clock 25 MHz has a score of 18432
HDMI:EDID best score mode is now CEA (5) 1920x1080i @ 60 Hz with pixel clock 74 MHz (score 4773832)
HDMI:EDID DMT mode (5) 640x480p @ 72 Hz with pixel clock 31 MHz has a score of 22118
HDMI:EDID CEA mode (6) 1440x480i @ 60 Hz with pixel clock 27 MHz has a score of 45736
HDMI:EDID DMT mode (6) 640x480p @ 75 Hz with pixel clock 31 MHz has a score of 23040
HDMI:EDID CEA mode (7) 1440x480i @ 60 Hz with pixel clock 27 MHz has a score of 45736
HDMI:EDID DMT mode (8) 800x600p @ 56 Hz with pixel clock 36 MHz has a score of 26880
HDMI:EDID DMT mode (9) 800x600p @ 60 Hz with pixel clock 40 MHz has a score of 28800
HDMI:EDID DMT mode (10) 800x600p @ 72 Hz with pixel clock 50 MHz has a score of 34560
HDMI:EDID DMT mode (11) 800x600p @ 75 Hz with pixel clock 49 MHz has a score of 36000
HDMI:EDID CEA mode (16) 1920x1080p @ 60 Hz with pixel clock 148 MHz has a score of 398248
HDMI:EDID DMT mode (16) 1024x768p @ 60 Hz with pixel clock 65 MHz has a score of 47185
HDMI:EDID best score mode is now CEA (17) 720x576p @ 50 Hz with pixel clock 27 MHz (score 5087208)
HDMI:EDID DMT mode (17) 1024x768p @ 70 Hz with pixel clock 75 MHz has a score of 55050
HDMI:EDID CEA mode (18) 720x576p @ 50 Hz with pixel clock 27 MHz has a score of 66472
HDMI:EDID DMT mode (18) 1024x768p @ 75 Hz with pixel clock 78 MHz has a score of 58982
HDMI:EDID CEA mode (19) 1280x720p @ 50 Hz with pixel clock 74 MHz has a score of 3617160
HDMI:EDID CEA mode (20) 1920x1080i @ 50 Hz with pixel clock 74 MHz has a score of 4232360
HDMI:EDID CEA mode (21) 1440x576i @ 50 Hz with pixel clock 27 MHz has a score of 45736
HDMI:EDID CEA mode (22) 1440x576i @ 50 Hz with pixel clock 27 MHz has a score of 56104
HDMI:EDID CEA mode (31) 1920x1080p @ 50 Hz with pixel clock 148 MHz has a score of 3232360
HDMI:EDID DMT mode (36) 1280x1024p @ 75 Hz with pixel clock 135 MHz has a score of 98304
HDMI:EDID preferred mode remained as CEA (17) 720x576p @ 50 Hz with pixel clock 27 MHz
HDMI:EDID has HDMI support and audio support
edid_parser exited with code 0


Misirlou
Posts: 4
Joined: Fri Sep 29, 2017 11:54 pm

Re: STICKY: Setting up HDMI output when video output is wrong.

Wed Oct 18, 2017 9:46 am

Edit: I solved the problem below, that a headless Pi with VNC Viewer always has a small default screensize, even if you choose another resolution. I had enabled the experimental graphics driver. Commenting out the following line in /boot/config.txt solved the problem:

Code: Select all

dtoverlay=vc4-kms-v3d
Original post:
~~~~~~~~~

I'm running Jessie headless with VNC Viewer, and have set up the /boot/config.txt file configured with:

Code: Select all

# uncomment if hdmi display is not detected and composite is being output
hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=2
hdmi_mode=85
This used to work ok, but now I'm stuck with the small default screen. I don't know what changed. It used to work ok. If I try with a fresh copy of Raspian it works, but I'd like not to have to reinstall everything from scratch. Is there something else I can check?

I tried doing it with raspi-config, with the "Raspberry Pi Configuration" menu, and manually editing config.txt (all of which resulted in the same config lines, above). I also tried uncommenting this:

Code: Select all

# uncomment to force a console size. By default it will be display's size minus
# overscan.
framebuffer_width=1280
framebuffer_height=720
But it makes no difference. Any help appreciated!

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BorbingoBoy
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Re: STICKY: Setting up HDMI output when video output is wrong.

Sun Oct 22, 2017 9:57 am

Hello.

I am constantly getting no HDMI output after shutting down my Pi 3 and turning it back on. I had to edit the config.txt many times only to have the HDMI output reset again after I shut the Pi down. Restarting doesn't change this, though.
3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456

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rpdom
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Location: Essex, UK

Re: STICKY: Setting up HDMI output when video output is wrong.

Sun Oct 22, 2017 10:23 am

BorbingoBoy wrote:
Sun Oct 22, 2017 9:57 am
Hello.

I am constantly getting no HDMI output after shutting down my Pi 3 and turning it back on. I had to edit the config.txt many times only to have the HDMI output reset again after I shut the Pi down. Restarting doesn't change this, though.
What did you change in config.txt and did the changes "stick" after power off?

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BorbingoBoy
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Location: Croatia
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Re: STICKY: Setting up HDMI output when video output is wrong.

Sun Oct 22, 2017 11:26 am

rpdom wrote:
Sun Oct 22, 2017 10:23 am
BorbingoBoy wrote:
Sun Oct 22, 2017 9:57 am
Hello.

I am constantly getting no HDMI output after shutting down my Pi 3 and turning it back on. I had to edit the config.txt many times only to have the HDMI output reset again after I shut the Pi down. Restarting doesn't change this, though.
What did you change in config.txt and did the changes "stick" after power off?
Sorry, I forgot to mention that I applied the force HDMI hotplug setting, and after that changed the resolution using raspi-config to preferred monitor resolution, because the force hotplug setting changes the resolution to the lowest one. Anyway, if I restart after applying the resolution, everything is okay, but once I shut it down, the force HDMI hotplug setting in config.txt gets commented.
3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456

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DougieLawson
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Re: STICKY: Setting up HDMI output when video output is wrong.

Sun Oct 22, 2017 5:55 pm

Are you using NOOBS?

Hold/tap the [SHIFT] key during boot-up. Use the NOBS rescue system config editor to set the parameters you want.
Microprocessor, Raspberry Pi & Arduino Hacker
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Please post ALL technical questions on the forum. Do not send private messages.

theatomicsoul
Posts: 4
Joined: Sat Nov 04, 2017 9:15 pm

Re: STICKY: Setting up HDMI output when video output is wrong.

Sat Nov 04, 2017 9:40 pm

The Raspberry Pi3 I just purchased is not properly recognizing the 8.9" screen I got to use with it.

The Pi works fine connected to my PC monitor but is giving an incorrect display / video feed when connected to my smaller (8.9") 2K screen.
When the pi connects to the 8.9" screen it cuts off the left half of the screen (shows black) and shows three vertacle stacked versions of the right half of the screen on that side.
The 8.9" screen works properly when connected to my PC.

What do I need to do to fix it to use the full 2560x1600 display?

Running Raspian with NanoDLP.
https://youtu.be/fLJjvJXFq60

I have this screen:
https://m.aliexpress.com/item/328050026 ... 8c0bCHEJX1

ElizabethMireles
Posts: 1
Joined: Tue Nov 07, 2017 1:16 pm
Contact: Website

Re: STICKY: Setting up HDMI output when video output is wrong.

Tue Nov 07, 2017 1:19 pm

I'm glad to see the post! I find it absolutely helpful, since i has the same problem. Thanks to this thread, I was able to find a proper solution!

PeterCoghlan
Posts: 2
Joined: Fri Dec 08, 2017 5:22 pm

Re: STICKY: Setting up HDMI output when video output is wrong.

Fri Dec 08, 2017 5:56 pm

I believe I have come across the same issue as BorbingoBoy above.

I have a VGA style monitor connected to my Raspberry Pi using a HDMI to VGA converter. With all the cables plugged in and the monitor turned on, when I power up the Pi, it fails to recognise the presence of the monitor and the monitor receives no signal.

If I add hdmi_hotplug=1 to /boot/config.txt, video is sent to the monitor when the Pi is powered up but this is not a satisfactory solution for several reasons. Firstly, doing this means I have to re-edit /boot/config.txt in order to use the RCA video output rather than just unplugging the HDMI cable. Secondly, The monitor ends up in 640x480 mode instead of the 1024x768 that it is capable of. I can add hdmi_group=2 and hmdi_mode=16 to /boot/config.txt but this is also unsatisfactory as I have several other monitors and I would like to be able to connect whichever monitor is convenient without having to edit /boot/config.txt to suit the particular monitor each time. I would therefore like to avoid using hdmi_hotplug=1 at all.

I have tried several other entries in /boot/config.txt such as config_hdmi_boost and hdmi_drive but non resulted in the monitor being activated after powerup of the Pi except for hdmi_hotplug=1

I discovered that if I reboot the Pi from an SSH session without powering it off, in the course of rebooting, the Pi notices the monitor is connected and sends video to it in the correct 1024x768 resolution ie everything appears to work the way it should. It is only when the Pi is started by powering it on that the problem arises.

My suspicion is that my el-cheapo HDMI to VGA converter takes longer to start up from power-on than the Pi does and when the Pi attempts to query the monitor regarding it's resolution etc, the converter is not yet ready to pass on the request and the Pi decides no monitor is present.

Any suggestions on how to check out my theory?

Is there any way to get the Pi to wait longer at boot time before it queries the HDMI monitor port?

Failing other solutions, any recommendations for a HDMI to VGA converter that does not have this issue?

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FTrevorGowen
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Re: STICKY: Setting up HDMI output when video output is wrong.

Fri Dec 08, 2017 7:16 pm

PeterCoghlan wrote: ...
My suspicion is that my el-cheapo HDMI to VGA converter takes longer to start up from power-on than the Pi does and when the Pi attempts to query the monitor regarding it's resolution etc, the converter is not yet ready to pass on the request and the Pi decides no monitor is present.
Any suggestions on how to check out my theory?
Is there any way to get the Pi to wait longer at boot time before it queries the HDMI monitor port?
Failing other solutions, any recommendations for a HDMI to VGA converter that does not have this issue?
1) It may not provide the hotplug signal
2) It may not "pass through" some of the display info. (some pass their "name" rather than that of the display)
3) If it's not externally powered, but can be, that may help.
FWIW, these are the ones I've tried:
http://www.cpmspectrepi.uk/raspberry_pi ... erter.html
http://www.cpmspectrepi.uk/raspberry_pi ... rter2.html
http://www.cpmspectrepi.uk/raspberry_pi ... erter.html
http://www.cpmspectrepi.uk/raspberry_pi ... Audio.html
and notes on "Display Optimisation" which may be of interest and show behaviour "2" happening:
http://www.cpmspectrepi.uk/raspberry_pi ... GA_Monitor
Trev.
Usually running Raspbian Jessie on up to 9 of 13 Pi's (an A, B1, B2, B+, P2B, 3xP0, P0W) and Stretch on my P3B, B+, A+ and a B2. See: https://www.cpmspectrepi.uk/raspberry_pi/raspiidx.htm

PeterCoghlan
Posts: 2
Joined: Fri Dec 08, 2017 5:22 pm

Re: STICKY: Setting up HDMI output when video output is wrong.

Fri Dec 08, 2017 10:21 pm

Many thanks for the pointers.

My monitor is a Fujitsu Siemens SENICVIEW A15-1

tvservice -n reports device_name=FUS-A15-1

tvservice -d followed by edidparser reports HDMI:EDID monitor name is A15-1

These both clearly relate to the monitor rather than the HDMI to VGA converter and gives me no clue as to the identity of the converter I am using. The only thing written on my converter is "VICTSING". It looks rather like the PSG90916 unit in one of the links except that mine is black and has no micro USB or sound ports and not being externally powered, I cannot try powering it before I power up the Pi.

I think it does pass the hotplug signal though because the monitor is successfully detected without my having specified hdmi_hotplug=1 when I reboot the Pi without powering it off. Also, I can disconnect the VGA cable from the monitor and plug in into a different monitor and tvservice -n and tvservice -d then report the name of the new monitor.

As an aside, I also notice that the Pi / converter combination sends enough power down the VGA cable to the monitor to enable the EDID to work even if the power cable to the monitor is disconnected.

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