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Howto Install Vietnamese Input Method ibus-unikey in Ubuntu

admin — Fri, 07 May 2010 16:17:49 +0000

IBus (Intelligent Input Bus for Linux/Unix OS) become the main Language Input Method manager since Ubuntu 9.10. For Vietnamese people and ones who want to learn and type Vietnamese language, unikey is usually the best choice in Windows and Linux as well. This article is going to guide to install ibus-unikey in Ubuntu.

Ibus-Unikey package is maintained by Ubuntu-VN community, so ibus-unikey or scim-unikey is always in their PPAs. So we can easily install and get package update whenever the new version is released.

Add Ubuntu-VN repository

For Ubuntu from 9.10, Ubuntu 10.04, just open Terminal and type this command:

$sudo add-apt-repository ppa:ubuntu-vn/ppa

Update system and install ibus-unikey

Next, just update your system:

$ sudo apt-get update

And insall ibus-unikey package:

sudo apt-get install ibus-unikey

DONE. Now you can choose to add Unikey in the Vietnamese language selection of IBus Preferences.

Rating: 8.0/10 (6 votes cast)

How to fix libdc1394 error: Failed to initialize libdc1394

admin — Fri, 07 May 2010 05:39:37 +0000

I am doing a project about Mobile Robot Teleoperation which uses OpenCV for Computer Vision, but I always get error: libdc1394 error: Failed to initialize libdc1394

The reason is: There is no file /dev/raw1394 since the raw1394 driver is not loaded. So you need to insert that driver:

$ sudo modprobe raw1394

Check your permission access to that dev file:

$ ls -la /dev/raw1394

If you don’t have rw access right, need to change that permissons:

$ sudo chmod a+rw /dev/raw1394

Credit for Viktors Petrovs from this bug

Rating: 10.0/10 (1 vote cast)

RTAI Conference Papers

admin — Sat, 03 Apr 2010 11:04:58 +0000

Last week, I have introduced to RealTime Application Interface for Linux, now I would like to give you some RTAI Conference Papers. Those papers could be a very good reference for everyone who is working with RTAI, as well as people doesn’t play with RTAI before to have more motivation.

1. PC-based feedback acceleration control using Linux RTAI

ABSTRACT
Linux operative system, extended with the real time application interface (RTAI), makes it possible to realize industrial motion controls. This requires general purpose processors (GPPs) instead of dedicated DSPs or microcontrollers. RTAI offers the possibility of designing and developing motion controls using high level object languages (i.e., Simulink). The main advantages brought using Linux-RTAI and a PC as a controller platform are: very reduced time for development, diagnostics, design of controls; cost reduction offered by the open-source status of the operating system; high availability of the hardware. This paper shows that such a system offers adequate digital programming and signal processing capabilities to make real time motion control applications. An industrial-PC based acceleration control is presented and points of strength of RTAI solution are shown.

2. Industrial motion control applications using linux RTAI

ABSTRACT
RTAI extension to Linux operating system makes it possible to perform Hard Real-Time (HRT) controls using a commercial PC and utilizing open-source code. This paper details a software installation process, along with the suitable hardware chosen for realizing motion controls using Linux-RTAI. Advantages offered by the possibility of designing and developing motion controls using the powerful tools of high level object-languages (i.e. Simulink) are described. It is proven that the combination of Simulink as a development environment and Linux-RTAI PC as a controller platform brings advantages that can be greatly appreciated in industrial motion control applications, such as: very reduced time for development, diagnostics, design of controls; adequate control performance; cost reductions offered by the open-source status of the operating system.

3.Scilab/Scicos and Linux RTAI – a unified approach

ABSTRACT
This paper presents a rapid controller prototyping environment completely based on open source software. GNU/Linux with the RTAI extension is used as a hard real-time operating system. The Scilab/Scicos suite permits performance of all phases of the control system design. A modified Scicos code generator directly generates the C-code for the Linux RTAI environment. Finally, the generated hard real-time task runs as a user space application on a standard PC using the COMEDI drivers to interface with the real plant. A GUI application facilitates the user to interact with the running real-time task (data visualization, data collection, parameters tuning) directly from any PC in the network. All needed software is available on the Web and can be freely downloaded. Some applications are presented to demonstrate the potentialities of the presented suite.

4. A Hardware-In-the-Loop Simulation System of Diesel Engine Based on Linux RTAI

ABSTRACT
In this article, the rapid prototyping technology is used to develop a hardware-in-the-loop simulation system for the diesel engine electronic control unit development. The hardware- in-the-loop simulation is based on Linux RTAI system, an open source hard real-time extension of the Linux Operating System, at low costs and within industrial standards. It exploits standard x86-based computing platforms provided with real-time Linux software in combination with generic computer-aided design software (Matlab/Simulink). One of its main characteristics is that it can automatically generate the real-time simulation code for many target processors, which runs under Linux RTAI operating system.

5.Monitoring applications of electrical and climate data for PV systems using Linux RTAI

ABSTRACT
This work presents the design and development of an innovative system aimed at detecting, recording and transmitting electrical and climate data from a PV field. Data are to be taken both from the PV modules and from the power conditioning system of a given PV field, through appropriate sensors, to monitor: climate data (irradiance, temperature), electrical quantities (voltage, current, power), performance of the PV generator as a function of climate parameters, performance of the power conditioning system over different working conditions. The system will exchange data through a communication network (i.e. Ethernet/TCP-IP) to download data, visualize quantities and operative states. The proposed system is designed to be integrated into any PV field, independently from the plant layout, the inverter type, the presence of preexisting data loggers, sensors, etc. Such a result is achieved using an open architecture, which assures an extremely high flexibility of utilization.

6.Real time distributed control systems using RTAI

ABSTRACT
The paper outlines the design and implementation of the Real Time Application Interface (RTAI) for Linux, as used for high performance local/distributed control systems implemented on low cost off the shelf general purpose computers. Its native lean real time middleware layer is described along with its use in an advanced tool to easily manage and monitor complex networked control systems.

7. RTAI-based execution environments for function block based control applications

ABSTRACT
The IEC 61499 standard has been recently adopted to promote a more flexible development process in the control and automation domain. The standard mainly deals with modeling issues leaving a lot of model execution details open. Different research groups are already working for the development of execution environments for the defined component model, proposing implementations with different execution semantics. This paper discuss the semantics of the execution environment and presents two execution environments, which although independently developed share a similar view of IEC61499 execution semantics and are both implemented over RTAI (real time application interface), a real-time Linux-based platform.

8. Performance Comparison of VxWorks, Linux, RTAI and Xenomai in a Hard Real-time Application

ABSTRACT
We report on a set of performance measurements executed on VMEbus MVME5500 boards equipped with MPC7455 PowerPC processor, running four different operating systems: Wind River VxWorks, Linux, RTAI, and Xenomai. Some components of RTAI and Xenomai have been ported to the target architecture. Interrupt latency, rescheduling and inter-process communication times are compared in the framework of a sample real-time application. Performance measurements on Gigabit Ethernet network communication have also been carried out on the target boards. To this purpose, we have considered the Linux IP stack and RTnet, an open-source hard real-time network protocol stack for Xenomai and RTAI, which was ported to the considered architecture. Performance measurements show that the tested open-source software is suitable for hard real-time applications

9. RTAI-based execution environments for function block based control applications

10. Rapid control prototyping with Scilab/Scicos/RTAI for PC-based ARM-based platforms

ABSTRACT
This document describes three didactic system with a Rapid Control Prototyping (RCP) suite based on Scilab/Scicos and a PC computer. Servomechanisms with wire signal transmission and PID as well as a fuzzy controller are presented. The servomechanism with wireless signal transmission is also described. As the RCP suite based on Scilab/Scicos/RTAI was successfully used in the servo controller development on a PC platform, the concept of a tool-chain for RCP on an embedded platform with ARM processor is discussed. The TS-7300 embedded system with RTAI real-time operating system is described. The changes in Scilab/Scicos needed to interface the generated controller code to TS-7300 are presented. The didactic use and a possible commercial use of the tool-chain is indicated. The didactic use is focused on controllers tuning, friction and long delays influence on servomechanism control and embedded control system development.

Note: They are all papers I have downloaded and read, so I just share it with the one who wants it.

Rating: 0.0/10 (0 votes cast)

The best CHM Viewer in Ubuntu Linux

admin — Tue, 30 Mar 2010 15:52:32 +0000

What is CHM ?

Let’s have a look at Wikipedia:

Microsoft Compiled HTML Help is a proprietary format for online help files, developed by Microsoft and first released in 1997 as a successor to the Microsoft WinHelp format. It was first introduced with the release of Windows 98, and is still supported and distributed through Windows XP and Vista platforms.

“.chm” is one kind of headache for Linux users so let’s find the best useful CHM viewer for Ubuntu/Linux. I have some great eBooks but in CHM format, so I have been always finding a good and useful CHM Viewer for my system.

My requirements of a CHM Viewer program include:

Be able to read .chm file (of course)
Good looking
Support non-English language
Still under development since by time new Ubuntu version releases, so it may have some bugs when we upgrades our systems.

Let’s go to Applications, Ubuntu Software Center and type chm you could see there are 5 available CHM viewer apps in Ubuntu server:

They are all active projects, but I did have a look at all features and tried all but only KchmViewer can satisfy me. Let’s have a look at its features

Kchmviewer is a free, open-source chm (MS HTML help file format) viewer written in C++ for Unix, Mac and Windows systems. Unlike most existing CHM viewers for Unix, it uses Trolltech Qt widget library, and could optionally be compiled for better KDE integration. It does not require KDE, but may be compiled with full KDE support, including KDE widgets and KIO/KHTML.

The main advantage of kchmviewer is the best support for non-English languages. Unlike other viewers, kchmviewer in most cases is able to correctly detect the chm file encoding and show it. It correctly shows the index and table of context in Russian, Spanish, Romanian, Korean, Chinese and Arabic help files, and with new search engine is able to search in any chm file no matter what language it is written.

kchmviewer is written by George Yunaev (see the contacts page for details), and is licensed under GNU GPL license. It uses chmlib, and some ideas and code from xchm.

You can have a look at here in more detail. I can give you some reasons why I love this app more than others:

Written by using QT Library which is the best cross-platform library. You will feel that each button and edges are very smooth and clean.
Support non-English languages
Can view .chm files in tabs. I am always tired of managing a lot of opened files in desktop, so this feature helps me a lot then

How to install KChmViewer

Just open Terminal:

sudo aptitude install kchmviewer

and type your super user password, and enjoy the program by going to Applications >> Office

Rating: 7.4/10 (5 votes cast)

How to setup Video calls in Skype on 64-bit Ubuntu system

admin — Sat, 27 Mar 2010 14:48:20 +0000

Skype is a software to make free video and voice calls, send instant messages and share files with other Skype users. You can use Skype in almost famous platforms: Windows, Linux, Mac OS and for your mobiles as well. For Linux users, you can easily download and install Skype binary package from here.

With the 32-bit Ubuntu box, you simply just plug Webcam or use build-in webcam, turn Skype and enjoy chatting with your girlfriend, however with the 64-bit counterpart, you have to do some tricks to make it works. Otherwise, you can’t see anything even you still can see camera file in /dev/video0

1. You have to locate v4l1compat.so library in your system. User Terminal and type this:

$ find / -name v4l1compat.so 2>/dev/null
/usr/lib/libv4l/v4l1compat.so
/usr/lib32/libv4l/v4l1compat.so

Use /dev/null to ignore errors can appear during searching for that lib.

2. You then have to load that library before other Skype libs by using LD_PRELOAD. You can read this article to see how LD_PRELOAD works: Modifying a Dynamic Library Without Changing the Source Code

So now create a file in anywhere you like with this folowing content:

#!/bin/bash
LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so /usr/bin/skype

And don’t forget to set execute permission to that file (chmod u+x ./yourfile).

Rating: 10.0/10 (1 vote cast)

Introduce to RealTime Application Interface for Linux

admin — Fri, 26 Mar 2010 15:21:19 +0000

Nowadays, people is looking for RealTime solutions for their products, since their tasks have to be done very accurately. One more reason is Linux OS usually to be integrated into embedded IC ( Arm, PowerPC, … ). In term of Realtime OS, there are several wellknown Real-Time OS: QNX, VxWorks, RTAI.

VxWorks comes from WindRiver company, is the most expensive and well supported Real-Time commercial product. It has been used for many years in many famous labratory to do some real-time needed experiments like human interactions, … It costs around 4000$ per license. In additions, WindRiver has a university program which can donate to your university for several licenses for 3 years, read more.

I am not familiar with QNX so just have a look at Wikipedia:

As a microkernel-based OS, QNX is based on the idea of running most of the OS in the form of a number of small tasks, known asservers. This differs from the more traditional monolithic kernel, in which the operating system is a single very large program composed of a huge number of “parts” with special abilities. In the case of QNX, the use of a microkernel allows users (developers) to turn off any functionality they do not require without having to change the OS itself; instead, those servers are simply not run.

The system is quite small, with earlier versions fitting on a single floppy disk.

QNX Neutrino (2001) has been ported to a number of platforms and now runs on practically any modern CPU that is used in the embedded market. This includes the PowerPC, x86 family, MIPS, SH-4 and the closely related family of ARM, StrongARM and XScale CPUs.

Those two QNX and VxWorks for commercial purposes and short-time development products, but, by contrast RTAI is the best choice for one who doesn’t want to spend big money, since it supports a lot of platforms. RTAI stands for RealTime Application Interface for Linux, which lets you write applications and runs it in real time (strict timing constraints) for your Linux distributions. In fact, RTAI is not a RealTime OS, it is just a patch for your Linux distributions since Linux OS itself doesn’t have realtime feature. Like Linux OS, RTAI is totally free and having a big community which can support you during developing your system.The famous and wellknown distributor is Roberto.

RTAI Homepage: https://www.rtai.org/

At this moment, RTAI supports following architectures:

x86 (with and without FPU and TSC)
x86_64
PowerPC
ARM (StrongARM; ARM7: clps711x-family, Cirrus Logic EP7xxx, CS89712, PXA25x)
m68k (supporting both MMU and NOMMU cpus)

The latest version is RTAI 3.8 which was released in 02/16/2010.

How to get started ?

I am sure that you will get a lot of issues during playing with RTAI, so you can get supports from serveral sources:

RTAI website: https://www.rtai.org/
Install RTAI & Comedi & ScicosLab & QRtaiLab on Kubuntu Jaunty
RTAI mailing list: https://mail.rtai.org/cgi-bin/mailman/listinfo/rtai

Note: You need to add RTAI certification in your web browser to view RTAI contents, otherwise you can’t access it.

Some useful articles out there:

Rating: 6.0/10 (1 vote cast)

How to solve: Maximum number of clients reached: Gtk-WARNING **: cannot open display in Ubuntu 9.10 64 bit

admin — Thu, 18 Mar 2010 08:06:35 +0000

I am currently running Ubuntu 9.10 AMD64 bit in my Desktop and there are some issues with the warning:

Maximum number of clients reached

Gtk-WARNING **: cannot open display in Ubuntu 9.10 64 bit

After several mins running my OS, I can’t open any program like gedit, VLC, .. even the Terminal. Luckily I still had one terminal left, so I tried to see what the message if I open gedit:

$gedit

And that message come out. Actually I didn’t know what is wrong with my system even I had a fresh installation of Ubuntu. And this one has never happened before with 32-bit Ubuntu.

I had to spend a lot of time on searching Google and found out that there are a lot of people have the same problems, but it seems to be happened only in 64-bit system. And I never got good answer how to solve at all.

Yesterday, I found one thread mention about Maximum number of clients reached on Ubuntu forums and finally I got the way to solve it.

Causes

It happens only when you install Lastpass extension for Google Chrome browser in Ubuntu 9.10 64 bits. If you remove that extensions and close all Chrome tabs, everything runs again.

Lastpass is one of my best favorite plugins in Firefox and Chrome as well. Read more: LastPass – the best password manager for IE, Firefox, Safari, Google Chrome

How to solve

You can fix that problem by 2 ways:

If you don’t wanna use Lastpass extension, just remove it from Google Chrome and close all tabs. That’s all
If you still wanna use Lastpass extension, don’t install from Google Chrome page, just install it from Lastpass page: https://lastpass.com/lpchrome_bin.crx (Thanks Bob from Lastpass)

Have fun with Google Chrome and Lastpass.

Rating: 0.0/10 (0 votes cast)

How to install packages from GetDeb

admin — Mon, 30 Nov 2009 18:56:33 +0000

Homepage: http://www.getdeb.net

Today, I went to the GetDeb website just because I wanted to download the latest Filezilla FTP application for my Ubuntu 9.10, and I was really surprised that now they have a very great website and also their own Repository. Before it was so difficult to access this website, even couldn’t see anything, I thought just because it is so famous among websites for very huge Ubuntu fans, and now they change to the new server and also technical supports. Thank GetDeb people so much for their efforts to bring a lot of benefits to Ubuntu fans. In here, you can easily find some famous applications such that Pidgin, Filezilla, …

As you know that, there are 2 ways to install a package: compile from the source or install from Ubuntu repositories. So GetDeb people just compile every new sources into ready install .deb files, so everyone can just download them and install. Therefore, it take just little time for everyone.

There are 2 ways you can download packages from GetDeb website:

Go directly to GetDeb and download the latest .deb files and install manually but you will not know whenever there is a update package without always checking this website.
Install GetDeb repository. This post almost covers the second method.

Install repository

Use the following instructions:

Install the getdeb package.
Or configure the repository manually:Go to System-Administration-Software Sources, Third-Party Software tab, Add:
```
deb http://archive.getdeb.net/ubuntu karmic-getdeb apps
```

Add the repository GPG key, open a terminal window and type:

wget -q -O- http://archive.getdeb.net/getdeb-archive.key | sudo apt-key add -

Click the “Install this now” button below the screenshot of the desired application.

Have fun with your always update packages.

Rating: 10.0/10 (1 vote cast)

Ubuntu 9.10 runs very fast and stable on Notebook MSI VX600

admin — Sat, 14 Nov 2009 08:25:44 +0000

As in the post How to install Ubuntu 9.04 on notebook MSI VX600, I had to disable ACPI, … to make Ubuntu 9.04 work in my notebook, but the CPU always went height when I open the Firefox browse, especially some flash sites. So at that time, I couldn’t enjoy Ubuntu system in my notebook.

But now, after near one month already, I move to use Ubuntu as the primary OS in my notebook. Ubuntu 9.10 makes a lot of changes, so it runs so stable, smoothly.

Another interesting thing in Ubuntu 9.10 is Ubuntu One, which can automatically sync the personal data in secure with many computers which have same Ubuntu One account. But for me, I still choose Dropbox, instead of Ubuntu One, because it can sync faster and more stable than Ubuntu One.

Life is free !

Rating: 0.0/10 (0 votes cast)

How to upgrade Pidgin and fix Yahoo problem in Ubuntu 9.04

admin — Fri, 26 Jun 2009 03:06:27 +0000

Some days ago, I couldn’t even sign in my Yahoo account in Pidgin. At that time, I guessed that having some problems and was waiting for upgrade version of Pidgin. Finally, the new version 2.5.7 has been released on 20th June wih new bug fix.

Version 2.5.7 (06/20/2009)

Yahoo Protocol 16 support, including new HTTPS login method; this should fix a number of login problems that have recently cropped up. (Sulabh Mahajan, Mike “Maiku” Ruprecht)
Only display the AIM “Unable to Retrieve Buddy List” message once per connection. (Rob Taft)
Blocking MSN users not on your buddy list no longer disconnects you.
When performing operations on MSN, assume users are on the MSN/Passport network if we don’t get network ID’s for them.

In my option, I always want to get newest packages from their repositories instead of default Ubuntu’s repositories, so we need to update PPA.

Step 1: Setup PPA

To setup the PPA, copy-and-paste these commands into a terminal:

sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com \
     67265eb522bdd6b1c69e66ed7fb8bee0a1f196a8

and

echo deb http://ppa.launchpad.net/pidgin-developers/ppa/ubuntu \
    `lsb_release --short --codename` main | \
 sudo tee /etc/apt/sources.list.d/pidgin-ppa.list

Step 2: Update pidgin

Update repositories by typing command:

sudo apt-get update

Now you will be able to get new Pidgin version.

Have fun and enjoy your Pidgin messenger.

Please have a look at http://www.pidgin.im for more information.

Rating: 10.0/10 (1 vote cast)