Raspberry Pi 2 and a VGA monitor

The Raspberry Pi 2 (RPI2) model B (more details) comes with many input/output connectors and of which its display output is using HDMI type A. This HDMI is also known as Full HDMI.

Model B is the big brother of Model A+ that is much more cheaper for specific implementation in an embedded project where the most minimal use of electrical power is needed.

The RPI2 can be hooked up to a decent monitor or projector using VGA connectors. All that is needed is a HDMI to VGA adapter. This adapter may comes with additional functions like audio output, additional power source or USB. Price differences are huge but here is an example that I got from online and it works just fine with the NEC AccuSync LCD52v monitor.

HDMI to VGA cable plugged to RPI2 and female VGA.

Done.

Howto clone Ubuntu 10.04 display on a projector

The Ubuntu 10.04 on HP ProBook 4420s was able to connect to the projector by pressing the fn+f4 keys. This cycled through 4 modes but nothing that allowed me to view a clone of the display on laptop and projector.

Here are steps to resolve this (results in 800x600 for most projectors).

Step 1: Login to laptop and then plug-in projector.

Step 2: Identify the mode available for 800x600 and add to the existing display modes

xrandr -q
cvt 800 600

example of output:
nicholas@nicholas-laptop-kde:~/scripts$ xrandr -q
Screen 0: minimum 320 x 200, current 1366 x 768, maximum 8192 x 8192
VGA1 disconnected (normal left inverted right x axis y axis)
LVDS1 connected 1366x768+0+0 (normal left inverted right x axis y axis) 310mm x 174mm
1366x768 59.6*+
640x480 59.9

$ cvt 800 600
# 800x600 59.86 Hz (CVT 0.48M3) hsync: 37.35 kHz; pclk: 38.25 MHz
Modeline "800x600_60.00" 38.25 800 832 912 1024 600 603 607 624 -hsync +vsync

Step 3: Create following script called clone800x600.sh that add the 800x600 capability to the display and enables on both projector and laptop. Notice the bold fonts above is copied to the first xrandr command below.


#!/bin/bash
xrandr --newmode "800x600_60.00" 38.25 800 832 912 1024 600 603 607 624 -hsync +vsync
xrandr --addmode LVDS1 800x600_60.00
xrandr --output VGA1 --off
xrandr --output LVDS1 --off
xrandr --fb 800x600
xrandr --output VGA1 --mode 800x600 --rate 60
xrandr --output LVDS1 --mode 800x600_60.00 --same-as VGA1 --auto --scale 1x1 --panning 0x0

Step 4: Make executable and run the script

chmod u+x clone800x600.sh
./clone800x600.sh

To switch back to original settings, press fn+f4.

Next, try to get it working at higher resolution that the projector can support.

KDE 4.2 with Dual Monitor

I just upgraded to KDE4.2 today on Kubuntu Interpid. One of the first items I am testing is the ability to use the display on my laptop and the monitor/projector at the same time. This is known as multihead and previously the Xinerama was used to have two different screens with one X server (the engine behind the graphics display on Linux).


The KDE 4.2 Plasma control (top right corner of the screen) Zoom Out function allowed the laptop screen to have a different background and widget from the monitor/projector. This really made an impressive environment for customisation.

This is great for presentation as the OpenOffice.org 3 have full capability to show the slides on one screen while previewing on another screen. The KDE4.2 provided the variable KDE_MULTIHEAD=false that allowed the same display for both the displays. Initially I changed this environment variable to true, but nothing happened.

The Intel site http://intellinuxgraphics.org/dualhead.html gave some good tips to get what I was looking for. The steps below allowed the multihead function to work when the VGA cable is plugged at the Login screen. To revert back to the dual head (where both laptop and monitor/projector displayed the same output), return to the Login screen and unplug the VGA cable. The X server should be restarted.

Step 1: Backup the /etc/X11/xorg.conf

Step 2: Replace the xorg.conf with the following

Section "Device"
Identifier "Configured Video Device"
Driver "intel"
Option "FramebufferCompression" "off"
Option "monitor-LVDS" "internal"
Option "monitor-VGA" "external"
EndSection

Section "Monitor"
Identifier "internal"
EndSection

Section "Monitor"
Identifier "external"
Option "RightOf" "internal"
EndSection

Section "Screen"
Identifier "Default Screen"
Monitor "internal"
Device "Configured Video Device"
SubSection "Display"
Virtual 2560 1024
EndSubSection
EndSection

Section "ServerFlags"
Option "AIGLX" "false"
EndSection

Step 3: Reset the X server
Logout and restart the X by pressing Alt+e
Login again and you should have the new setting applied.

R60 laptop and projector display

To have the R60 Laptop be able to display with the projector while being able to view the laptop screen I have some suggestions for Linux Ubuntu (Gutsy 7.10) and CentOS 5.1.

Firstly, Gutsy detected and is using an Intel experimental driver for the 945. CentOS detected the driver as Intel i810.

There are three methods that you may want to try out. Please do drop me a comment if it works on other distros or record here if you have problems.

1) Modify xorg.conf file
Modify the options for the graphical device in the /etc/X11/xorg.conf file. Make sure the file have a backup.
1.1) Linux Ubuntu
a) vi /etc/X11/xorg.conf
From:
Section "Device"
Identifier "Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller"
Driver "intel"
BusID "PCI:0:2:0"
EndSection

To:
Section "Device"
Identifier "Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller"
Driver "intel"
BusID "PCI:0:2:0"
Option "MonitorLayout" "NONE,LFP+CRT"
Option "DevicePresence" "true"
Option "CheckLid" "false"
EndSection

Save the file.

b) Plugin the projector and reboot.

1.2) Linux CentOS 5
a) vi /etc/X11/xorg.conf
Find the section "Device" and edit to include the BusID and the 3 options. They are self explainatory.

Section "Device"
Identifier "Videocard0"
Driver "i810"
BusID "PCI:0:2:0"
Option "MonitorLayout" "NONE,LFP+CRT"
Option "DevicePresence" "true"
Option "CheckLid" "false"
EndSection

Save the file.

b) Logout and plugin the projector. If you still cant see the displays, then reboot without the projector plugged in. Plug in when at the login screen.



2) Restarting X
Based on my postings to ubuntuforums titled "HOWTO GUTSY: Laptop dual display with projector/external screen" (Oct 20, 2007). Those who do not want to touch the xorg.conf file can do the following:


a) Start Gutsy and stay at the login screen or Press Ctrl+Alt+Backspace
b) Plug in the external display cable
c) Log-in and you can see the two screens. Play a movie and it appears on the external screen.

Next problem, You have watched the movie on the external screen now you want to remove the external screen and resume work as normal. This includes watching movies on the laptop.
a) Logout and remove the external screen cable.
b) At the login screen press Ctrl+Alt+Backspace
c) Login
d) Play a movie and it appears on the laptop screen.

3. Using command line.
For those who love to just make scripts or give command lines, I suggest using xrandr. However, if you have modified the xorg.conf file, the command may not always work.

a) Login as a normal user. Open a terminal to issue commands.
b) Plugin the external display cable (projector)
c) Type any of the following relevant lines:

xrandr --output VGA --auto
xrandr --output VGA --mode 800x600 --auto
xrandr --output VGA --mode 1024x768 --auto

d) To stop the projection, type

xrandr --output VGA --off

#end