Noobs - Auto change HDMI Source

[husvar]

Hi,

I am actually not sure if this issue is to be reported here but since I cannot find any forum for NOOBS...
My issue is that when I reboot the pi, the hdmi source in my tv changes to the raspberry hdmi automatically (at the raspberry rainbow).
I already edited the config.txt with the hdmi_ignore_cec_init=1 and I also disabled this in the XBMC, but It seems like the HDMI source is changed even before my rasbmc is loaded.

Does this make sense? Can I correct this anyway?
Thanks for the help.

[Phill Rymer]

sounds like tv is auto selecting input source not pi

[FTrevorGowen]

sounds like tv is auto selecting input source not pi

I agree - given that the O.P. can see the NOOBS RGB (rainbow) splash screen which is output several seconds before any O.S. (and associated "config.txt") begins to boot and use its (own) HDMI settings.
Trev.

[husvar]

Wicked thing is... I ever never seen this behavior with any other device. Until I got the pi, I actually was thinking this was a SCART-only behaviour. And it only happens in reboots, if I unplug and plug later on it does not auto change the source.

[alex_R]

Hey husvar,

I have run into the same problem as you, and also think that the fault lies with NOOBS. I have found a solution to the problem (see link below), but I need other people to test to confirm that the fault is NOOBS.
http://www.raspberrypi.org/phpBB3/viewt ... e0#p465409

[FTrevorGowen]

Wicked thing is... I ever never seen this behavior with any other device. Until I got the pi, I actually was thinking this was a SCART-only behaviour. And it only happens in reboots, if I unplug and plug later on it does not auto change the source.

IIRC, "SCART switching" works by simple switching of a "video signal present" (logic-)level on one of the pins which, I think, is "uni-directional" "source --> reciever". HDMI is different, AFAIK, there are "bi-directional" source/receiver present signals and "intelligent" devices like the Pi can set up a communication channel and both enquire about the receiver's capabilities and control it. This (for the Pi) happens during boot-up only (hence unplugging/re-plugging later has little/no effect upon the receiver's auto-source-detect mechanism - but that depends on the "intelligence" of the receiver too.)
Trev.

[husvar]

Hey husvar,

I have run into the same problem as you, and also think that the fault lies with NOOBS. I have found a solution to the problem (see link below), but I need other people to test to confirm that the fault is NOOBS.
http://www.raspberrypi.org/phpBB3/viewt ... e0#p465409

Thanks I will teste when I can. If you are right then the NOOBS is really creating this... Is there a forum for NOOBS where this problem can be reported or explained?

[FTrevorGowen]

Hey husvar,
I have run into the same problem as you, and also think that the fault lies with NOOBS. I have found a solution to the problem (see link below), but I need other people to test to confirm that the fault is NOOBS.
http://www.raspberrypi.org/phpBB3/viewt ... e0#p465409

Thanks I will teste when I can. If you are right then the NOOBS is really creating this... Is there a forum for NOOBS where this problem can be reported or explained?

Personally, I don't thinks this is a "fault" - on the occasions when I wish to use one of my Pi's with a T.V. I would be very pleased if it displayed immediately rather than having to remember to change the T.V.'s input to the correct HDMI channel. This is especially important in the context of NOOBS since you have a limited time window to press/toggle the "Shift" key to enter the recovery mode (this window can become quite short if you also have to wait for a wireless keyboard to be detected). AFAIK, during the recovery mode detection period (which takes place after the RGB splash screen) NOOBS is using a "default" HDMI setting optimised to give a display on the majority of HDMI monitors unless "HDMI safe mode" has been previously selected and made "permanent" (in the same way as composite video has to made "permanent"**). Any changes made to a particular O.S.' "config.txt" (eg. using NOOBS recovery mode's editor) to tweak those settings only apply as and when the O.S. boots up.
Trev.
**As shown in these screenshots of the installation process: http://www.cpmspectrepi.webspace.virgin ... ellow.html

[alex_R]

FTrevorGowen: I agree with your statement that this may not be considered a "fault" in/with NOOBS, but in relation to the original question, I identified that the "problem" exists (in my case) when NOOBS is present on the SD card.

If NOOBS does not respect the config file of the OS to be loaded, then this should be explicitly stated somewhere (which I have not been able to find so far) to prevent random "head-scratching" assumptions, such as, faulty cable or incorrect TV settings.

A possible solution would be for NOOBS to have its own config file in the root partition (or part of the install payload), but this might cause confusion as to which config values are in use at any give state of RPI booting up. But this discussion is beyond the scope of this topic.

For now, it is only important to determine where the "fault" lies for this post, and which solution solve the issue.

[FTrevorGowen]

FTrevorGowen: I agree with your statement that this may not be considered a "fault" in/with NOOBS, but in relation to the original question, I identified that the "problem" exists (in my case) when NOOBS is present on the SD card.
If NOOBS does not respect the config file of the OS to be loaded, then this should be explicitly stated somewhere (which I have not been able to find so far) to prevent random "head-scratching" assumptions, such as, faulty cable or incorrect TV settings.
A possible solution would be for NOOBS to have its own config file in the root partition (or part of the install payload), but this might cause confusion as to which config values are in use at any give state of RPI booting up. But this discussion is beyond the scope of this topic.
For now, it is only important to determine where the "fault" lies for this post, and which solution solve the issue.

@alex_R,
I understand that NOOBS default "HDMI setup/mechanism" is giving rise to a "problem" (not, perhaps, the same "problem" ) with some TV's but, so far, in my "following" of a number of NOOBS threads I have only come across ~3 similar issues (IIRC, none were reported in the "beta-testing" thread, for example). NOOBS does have its equivalent of a "config.txt", AFAIK, but that is somewhat different to those for the O.S.'s and the editing of such an "advanced topic". NOOBS main documentation can be found at: https://github.com/raspberrypi/noobs and, if you so wish, please raise an issue there.
Trev.

[husvar]

Hey husvar,

I have run into the same problem as you, and also think that the fault lies with NOOBS. I have found a solution to the problem (see link below), but I need other people to test to confirm that the fault is NOOBS.
http://www.raspberrypi.org/phpBB3/viewt ... e0#p465409

Thanks I will teste when I can. If you are right then the NOOBS is really creating this... Is there a forum for NOOBS where this problem can be reported or explained?

Just confirmed that if I install raspbmc without the noobs, the HDMI source does not change automatically.