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Monitor output problems.

Posted: Mon Nov 19, 2012 10:12 am
by PhillHS
Hi all,

I've just setup my pi with the latest riscos image and all seems to be working correctly except that I am having problems with the video output.

I'm using the composite video output with a TV / monitor combo that's capable of displaying up to 1280x1024. No matter what monitor I select I have two problems :

Firstly the output in all but the lowest resolutions is a trifle blurred, this seems worse under the mouse cursor as it moves, I suspect this may be down to using the composite video and may go away, if i used the HDMI output....I have a HDMI to DVI cable on order.

Secondly even if I select a 4:3 resolution such as 1024x768 the image is displayed with black bars on the left and right hand side as if it where trying to display a 4:3 image on a widescreen monitor which mine is not, is this a known problem ?

Cheers.

Phill.

Re: Monitor output problems.

Posted: Mon Nov 19, 2012 2:13 pm
by bhtooefr
Try putting the following line in config.txt (but this should be a default):

sdtv_aspect=1

That will force it to treat the composite display as 4:3.

Also, I would recommend only using a max of 800x600 over composite - anything higher will be too blurry.

Re: Monitor output problems.

Posted: Tue Nov 20, 2012 1:54 pm
by PhillHS
bhtooefr wrote:Try putting the following line in config.txt (but this should be a default):

sdtv_aspect=1

That will force it to treat the composite display as 4:3.
That worked, though oddly, the mouse won't move up to the left and right edges of the screen, it seems to stop a couple of cm in from each side :(
Also, I would recommend only using a max of 800x600 over composite - anything higher will be too blurry.
Yep that's what I found.

Anyway hopefully my HDMI to DVI converter will arrive today which should fix the problem.

Cheers.

Phill.

Re: Monitor output problems.

Posted: Tue Nov 20, 2012 3:46 pm
by michele.x
bhtooefr wrote:Try putting the following line in config.txt (but this should be a default):

sdtv_aspect=1

That will force it to treat the composite display as 4:3.

Also, I would recommend only using a max of 800x600 over composite - anything higher will be too blurry.
add also
sdtv_mode=2
and
into RiscOS select 640x512 resolution, or 640x480

Doing this only the scaler of the tv will upscale the signal.