Changing resolution of output B+ and NOOBS v1.3.9

[HAC]

Hi there, I have just got my first Pi, a B+, and I have it working well on a small wide screen TV. However, I ideally want to use an old PC monitor that I have as a display, but when I plug the Pi into the monitor, I get a black screen with the message "Over Range H: 67.5KHz V: 60.2KHz Max: 1024 x 768". I understand that it is possible to change the video output by using the NOOBS Config editor and have accessed this but I am unsure what to change and how to change it in order to change the display output of my Pi to 1024 x 768. I would be grateful for some useful directions. Many thanks.

[FTrevorGowen]

Hi there, I have just got my first Pi, a B+, and I have it working well on a small wide screen TV. However, I ideally want to use an old PC monitor that I have as a display, but when I plug the Pi into the monitor, I get a black screen with the message "Over Range H: 67.5KHz V: 60.2KHz Max: 1024 x 768". I understand that it is possible to change the video output by using the NOOBS Config editor and have accessed this but I am unsure what to change and how to change it in order to change the display output of my Pi to 1024 x 768. I would be grateful for some useful directions. Many thanks.

If you've used NOOBS to install Raspbian (or another O.S. that has the tvservice command) these notes of mine may help, FWIW:
http://www.cpmspectrepi.webspace.virgin ... tings.html
Trev.

[HAC]

Thanks for your post Trev and for your notes I see that the hdmi mode should = 17 for my 1024x768 VGA monitor. To change that do I simply change the number from what it is now "hdmi_mode=1" to "hdmi_mode=17" and click OK at the bottom of the Config editor. And reboot with the OS? Do I have to change the hash symbol first for this to work? New to this, as you can see!

Many thanks

Andy

[fruitoftheloom]

Thanks for your post Trev and for your notes I see that the hdmi mode should = 17 for my 1024x768 VGA monitor. To change that do I simply change the number from what it is now "hdmi_mode=1" to "hdmi_mode=17" and click OK at the bottom of the Config editor. And reboot with the OS? Do I have to change the hash symbol first for this to work? New to this, as you can see!

Many thanks

Andy

http://elinux.org/RPiconfig

[rpdom]

The hash symbol "#" at the front of a line means it is commented out and will be ignored.

hdmi_mode=1 means VGA which is 640x480 and should work on any monitor.

You say you are using an old monitor. What sort of interface does it have (VGA, HDMI, DVI-D)?

You should be able to get 1024x768 from your B+ without too much problem. You could always post the contents of your Raspbian config.txt here for people to look at.

[HAC]

Hi Trev

I am using an HDMI to VGA conversion cable recommended for use with the Pi. I am also using this to connect to the TV , which works OK so I don't think that is the problem. The config.txt reads:

display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=720

# 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=1
#hdmi_mode=1

# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
#hdmi_drive=2

#uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=4

# uncomment for composite PAL
#sdtv=2

Although I have played with HTML, this is all new to me - thanks for your help.

Andy

[FTrevorGowen]

Thanks for your post Trev and for your notes I see that the hdmi mode should = 17 for my 1024x768 VGA monitor. To change that do I simply change the number from what it is now "hdmi_mode=1" to "hdmi_mode=17" and click OK at the bottom of the Config editor. And reboot with the OS? Do I have to change the hash symbol first for this to work? New to this, as you can see!
Many thanks
Andy

I usually (when necessary) set both the "group" and "mode" to activate what tvservice reports as a "preferred" or, may be, a "native" option, eg.**:

Code: Select all

# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=1
#hdmi_mode=1
hdmi_mode=19

where "#hdmi_mode=1" was the "original", hash-commented-out example in config.txt
Trev.
** to get CEA "(native) mode 19: 1280x720 @ 50Hz 16:9, clock:74MHz progressive" for the BUSH TV (in my previous link)

[HAC]

OK, thanks Trev. I will give it a go and let you know how I get on.

Andy

[FTrevorGowen]

Hi Trev
I am using an HDMI to VGA conversion cable recommended for use with the Pi. I am also using this to connect to the TV , which works OK so I don't think that is the problem. The config.txt reads:

Code: Select all

display's size minus 
# overscan.
#framebuffer_width=1280
#framebuffer_height=720
# 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=1
#hdmi_mode=1
# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
#hdmi_drive=2
#uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=4
# uncomment for composite PAL
#sdtv=2

Although I have played with HTML, this is all new to me - thanks for your help.
Andy

By "an HDMI to VGA conversion cable" do you really mean an "HDMI-to-VGA Adapter** (box)" (better externally powered if your Pi is not a "B+")?
You will probably need to uncomment the "hdmi_force_hotplug=1" for such.
(It may be worth re-reading this section of my web page: http://www.cpmspectrepi.webspace.virgin ... GA_Monitor since the "available modes" may depend upon whether the VGA connection and/or adapter "passes through" DDC data from the display)
Trev.
** FWIW, this is the one I've used:
http://www.cpmspectrepi.webspace.virgin ... erter.html

[HAC]

Thanks Trev

Yes I have got a B+ so power is not an issue. I have just tried changing the mode to 17 but no luck, after the reboot it remained at 1 . I will try again, also changing the group also as you suggest and let you know what happens.

Cheers

Andy

[HAC]

Hi Trev

Tried changing both the hdmi group and hdmi mode settings to 17 but when I reboot, the return to 1 and still no joy with my PC monitor. Any ideas?

Cheers

Andy

[FTrevorGowen]

Hi Trev
Tried changing both the hdmi group and hdmi mode settings to 17 but when I reboot, the return to 1 and still no joy with my PC monitor. Any ideas?
Cheers
Andy

Just to clarify things - AIUI you're NOOBS-based and using it's editing tool (in recovery mode)?
NOOBS appends its settings to the end of a "skeleton" config.txt (for each O.S.) - is it possible that there are other "hdmi_group..." and/or "hdmi_mode..." settings (later) in the file overriding your edits?
The other possibility (IIRC) is that, at some point, some EDID data was downloaded via the adapter which has been saved and is (again) overriding your changes. There is an option to ignore such, but, not having needed to use it myself, I don't have the details to hand**.
Trev.
** Edit: Having checked http://elinux.org/RPiconfig#Video it appears to be "hdmi_ignore_edid=0xa5000080"

[HAC]

Yes, I am editing in NOOBS. The last link you sent states that the hdmi_mode=17 should be set with hdmi_group=2 I will give that a whirl and see if that works. Is there a way of editing rasp ism directly rather than using the NOOBS config editor?

Thanks, Andy

[FTrevorGowen]

...
Is there a way of editing rasp ism directly rather than using the NOOBS config editor?

Yes, but you need a computer that's running an O.S. or other software that understands Linux partition formats** - eg. another Linux box (or Pi), a "normal" P.C. booted up from a "Live Linux distro." on a DVD or USB stick, a MAC (I think) ... IIRC there are also "third party" Windows tools that allow copying to and from Linux and Windows-style partitions.
Trev.
** Rasbian's "/boot" directory resides in a Linux partition

[rpdom]

Rasbian's "/boot" directory resides in a Linux partition

I thought it was in a VFAT partition? Even with NOOBS. Just with NOOBS it isn't the first partition so Windows computers won't see it.

[FTrevorGowen]

Rasbian's "/boot" directory resides in a Linux partition

I thought it was in a VFAT partition? Even with NOOBS. Just with NOOBS it isn't the first partition so Windows computers won't see it.

Ooops ... you're correct (I re-checked after I posted - not fully "awake" yet ).
Trev.

[HAC]

OK thanks, becoming more complicated by the minute. I will let you know how I get on. Thanks again for your help.

Andy