2

I am having (very VERY) strange display issues on my Pi 3... I am using an HDMI-VGA Adapter ( https://www.adafruit.com/product/1151 ) which works perfectly fine (it works with many different devices with many different displays and display settings).

These settings work, and continue to work through reboots and halts (and restart performed with a reset switch):

hdmi_group=2

hdmi_mode=46

These work until the power itself is unplugged. Once that is done, the screen is black on boot (I don't get the "no signal" prompt on the screen as I would when there is no power or connection). Once this happens, the only way to get the previous settings to work is to first change them to:

hdmi_group=1

hdmi_mode=4

and reboot. This properly displays at 720p, as expected, all other settings I have tried at this point either result in the same kind of black screen, or some kind of "out of bounds" prompts on my screen. From here, I next have to change these settings to:

hdmi_group=2

hdmi_mode=4

and reboot. Note that if I try to use these settings PRIOR to the 720p, these will not work, they will just show a black screen. From here, I can now change those settings to:

hdmi_group=2

hdmi_mode=46

and reboot, and FINALLY we're back to the settings I want to use; and just like the previous settings, if I just jump to this, all I get is a black screen. And again, these settings work, and continue to work through reboots and halts (and restart performed with a reset switch), but as soo as I pull the power connection, I have to go through this process to get back to the "proper" display.

What is going on here???

  • 2
    I believe those cables draw some power via HDMI, so presumably this has something to do with it's state -- not sure (you can check this easily if you have an HDMI display), but I think after shutdown using the HDMI directly, without unplugging, you get "no signal". So the fact that doesn't happen with the adapter indicates it is continuing to draw power and output a signal. – goldilocks Sep 29 '16 at 15:53
  • Have you tried hdmi_cvt=1280 720 30 5 0 0 1? – Dmitry Grigoryev Sep 29 '16 at 16:04
  • This is like the guy who goes to the doctor and says, "Doctor, it hurts if I lift my arm like this" to which the doctor says, "then don't lift your arm like that." in the final analysis, be glad that you have found settings to make that converter work. I have a couple of them that I don't have time to figure out how to make work with the Rpi3. Kudos to you for making it work. The only question I see in the OP is "what is going on here?" - which would require setting up a duplicate setup, etc., etc. So, to the OP all I can say is that you will do best by finding the parameters that make it work – SDsolar Oct 1 '16 at 4:16
  • As golidlocks mentioned. The HDMI converters leach power from the HDMI port. Make sure you have a good power supply. 2Amp even 3 would be great. Another issue I can think of is CEC. Maybe your monitor/TV is having an issue with that most likely due to that. – Piotr Kula Oct 31 '16 at 12:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.