Begk
Posts: 2
Joined: Fri Jan 03, 2014 1:23 am

Good Video in a VGA monitor

Fri Jan 03, 2014 1:34 am

I was trying many different combinations to get correct video in a VGA monitor with resolution 1280x1024.
I get clear video with very low resolution with hdmi group=1 and hdmi mode=1.

I need the combination to get a resolution that matched the monitor recommended resolution of 1280x1024.
Anyone out there can help?
Thanks,

User avatar
rpdom
Posts: 17578
Joined: Sun May 06, 2012 5:17 am
Location: Chelmsford, Essex, UK

Re: Good Video in a VGA monitor

Fri Jan 03, 2014 6:21 am

Assuming you are using an HDMI to VGA converter, try "tvservice -m DMT" to see what modes are available.

On one of my systems I get

Code: Select all

pi@raspi:~$ tvservice -m DMT
Group DMT has 9 modes:
           mode 4: 640x480 @ 60Hz 4:3, clock:25MHz progressive 
           mode 6: 640x480 @ 75Hz 4:3, clock:31MHz progressive 
           mode 9: 800x600 @ 60Hz 4:3, clock:40MHz progressive 
           mode 11: 800x600 @ 75Hz 4:3, clock:49MHz progressive 
           mode 16: 1024x768 @ 60Hz 4:3, clock:65MHz progressive 
           mode 18: 1024x768 @ 75Hz 4:3, clock:78MHz progressive 
           mode 21: 1152x864 @ 75Hz 4:3, clock:108MHz progressive 
  (prefer) mode 35: 1280x1024 @ 60Hz 5:4, clock:108MHz progressive 
           mode 36: 1280x1024 @ 75Hz 5:4, clock:135MHz progressive 
(Note, that particular monitor is DVI-D, but I have used its VGA input with an adapter as well)

So if I had to set it manually I'd put hdmi_mode=35.

Have a look at http://elinux.org/RPi_config.txt#Video for a full list of modes and more info.

Begk
Posts: 2
Joined: Fri Jan 03, 2014 1:23 am

Re: Good Video in a VGA monitor

Sat Jan 04, 2014 5:19 am

Thanks for the information. Actually I tried the mode 35 but it didn't work.
anyway I started loading Pidora OS also and for some reason it picked up all the correct values and got me the perfect picture. So I copied the Config data from that boot, and pasted to the Raspbian and now it works well.
Thanks for your support. Below are the value:

sdtv_mode=0
sdtv_aspect=1
overscan_left=15
overscan_right=15
overscan_top=15
overscan_bottom=15
hdmi_drive=2

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