How to heal? Some keyboard keys are not working

It is a common problem that failing some keys in PC keyboard. But it become cumbersome while you type anything seriously. Replacing or repairing keyboard is not always easy, especially you are using a laptop. The seriousness of the problem depend on the failed key operation. If ENTER, DELETE, SPACE, SHIFT, CTRL, ALT etc are failed, your keyboard is almost at the worst state. Here I am trying share how to dilute this key failure effect.

Method 1 - On screen keyboard(Quickest way)
If you are doing something seriously, and don't have enough time to dismantle keyboard and clean, best method is to use virtual keyboard. On MS Windows, it is built in. You can access it by,
Start - All Programs - Accessories - Accessibility - On-Screen Keyboard
The fundamental advantage is that it is independent on how much keys in your keyboard are failed. Also you can access and use this utility completely using your mouse. In Linux, there is a similar utility named 'onboard' (use command 'onboard' to open it) and most probably it is built in. But it considerably lowers the typing speed.


Method 2 - Key mapper (Quicker enough)
SharpKeys from RandyRants is a good utility (for windows) to assign function of one key to another key. It can be done using a registry hack, but using Sharpkeys is a handy method. A good number of keys are there in your keyboard which are rarely or not used at all. Function keys F1, F2 ..., Win Key, Home, End, Print Screen, Pause/Break. If you use only left or right CTRL key is using other can be contributed for other function, because right and left CTRL keys are considered different. The same is applicable to SHIFT and ALT. Although this method slightly lowers your typing speed, you can still do everything.


Method 3 - Cleaning
Open it, clean well. If you are lucky, it will give life to your keyboard (I am unlucky).


Method 4 - Repair or Purchase
This is the last way. Of course, result will be positive.

LED Matrix pattern designer

LEDmatrix pattern designer is a tool used to generate matrix(2D) patterns in hex numbers for displaying LED matrix using a micro controller.

It is based on Qt framework and hence cross platform. It supports up to 16x16 matrix size. You can increase it by making minor changes in the sourcecode, but 16x16 is enough for most cases. This is done from the same pace of my previous project - ChaserDesigner. Only you need to do is that, specify the 2D pattern either manually or using the enhancing tools provided by the software. Then you can generate it's hex equivalent by a single click. A 2D pattern can be scanned either horizontally or vertically. The scanning mode can be switched in the software while making frames.

I think most of the features of the software are self explanatory. If you have any doubts, please comment. All files associated with this project are free to download.
Project source(Linux, Windows)
Windows executable
Required dlls for Windows executable

Just bought an Arduino, What's next?

This article briefly explain what is to be done just after purchasing an Arduino board. Even though the prerequisites of Arduino is less compared to other development boards, I think this article will be useful because Arduino is being popular among beginners. This article deals with the latest version of Arduino at the time of writing - it is Arduino UNO.
Setting up drivers
Connect Arduino to your computer via USB cable. It will power up from USB power. Now start Arduino IDE. If you have not Arduino IDE download from here. No need to install the software. Just extract using your favourite decompressing utility (my favourite is 7zip) and run the executable named 'Arduino'. Now you have to set up your IDE to work with your Arduino UNO. First select your hardware from Tools -> Board -> Arduino UNO (or your exact hardware name. If it is not listed, try to download the latest version). Next, select your serial port from Tools -> Serial Port. Selecting serial port is in different way different OS.
Linux
If the 'Serial Port' menu is not active, probably, your device is not connected properly. Try to reconnect. If more than one serial ports are shown in the menu, we need to find out which is the correct one. To do that, disconnect your arduino first. Then you probably need to restart the IDE. Then look at the 'Serial Port' menu and note down the listed COM ports. Then reconnect your device and track the newcomer. This is the easy way. Select it.
One of the problem I suffered while playing with arduino in my Ubuntu 10.04 LTS was that, the compilation of the program was a failure. It was a dependancy problem. So what I did is that, installed Arduino IDE as described here. But it was an older version and my device UNO is not listed in it. Then downloaded the newer version from the downloads page. That was really a tricky step!
MS Windows
In Windows, just after connecting your device to the PC, a device driver wizard appears and try to find the appropriate device driver for the device. It will take a while and at the end of the fight, it fails to find an appropriate driver. Close the wizard and go to 'Device Manger' (Either via Control Panel or by right clicking 'My Computer' then 'Manage'). Then you can find Aduino UNO as the unknown device. Right click on that and choose the option to manually install the driver. Then locate the directory where you have installed Arduino IDE. Then the system install the appropriate driver and now you can see your device on the list named 'Ports' in the Device Manger. In parenthesis, there will be the curresponding COM port number (eg: COM 4) . Then choose that COM port in the Arduino IDE.
Starting with 'Hello World'
The commonly accepted 'Hello World' in embedded devices is LED blinking. There is an example in the IDE itself. Open the file from File -> Examples -> Basics -> Blink
Look at the program. For an average C programmer, the program seems self-explanatory. To compile your program, choose Sketch -> verify/compile. Then to upload the executable to your device, choose,File -> upload to I/O board. If everything you have done is correct, you will get your Arduino programmed and starts working just after burning the program using the USB power. Disconnect it from USB and use in your standalone applications.
Read more..
Arduino Lanugage reference
Arduino Playground

Set up Toshiba L650 laptops after ubuntu installation

This article explains how to set up device drivers after installing Ubuntu in Toshiba laptops. Most probably Ubuntu will not support LAN, WiFi, Bluetooth and in some systems, anomaly in working of fan, battery are reported. Some of my problems like LAN setup, WiFi and Bluetooth have overridden and my battery is still showing some problems. I hope these instructions will be helpful for Toshiba Laptop users. Note that this article is a "how I did" type article rather than a "how to".
Some models of Toshiba Satellite are preloaded with Windows and some are not. In pre-installed models, try to make the system dual boot. There are a lot of tutorials for that and in Ubuntu, this is pretty easy compared to other distros. Anyway, I assume you have Toshiba system with a fresh Ubuntu installed. I used Ubuntu 10.04 LTS on by Toshiba L650-i5310.
Setting up Ethernet
My ethernet card was from Atheros Communications. A driver for Atheros is available from http://linuxwireless.org/download/compat-wireless-2.6 . Download and unzip the file. Then in terminal, cd into that folder. Then type the following code:

scripts/driver-select atheros
make
sudo make install

Then reboot the system.
Setting up Wireless
My Wireless LAN card was from Broadcom Corporation. The driver is readily available from ubuntu repository.

sudo apt-get install bcmwl-kernel-source
echo wl | sudo tee -a /etc/modules

Reboot the system.
Setting up Bluetooth
In bluetooth, I did nothing in Ubuntu and I installed a bluetooth driver from Toshiba in Windows 7. After that incident, my Ubuntu also start detecting bluetooth adapter and don't know how this happened.

Booting from CD ROM or USB devices

Booting from resources other than HDD is very simple, but the way in which configure your system for boot from a particular task may differ. First of all, you should know that, the boot configuration appearing on your monitor is independent of the OS, or any other peripherals connected to your system and it is occupied in your BIOS and it may vary for various type of mother boards. Nowadays, many people use liveCDs or liveUSB loaded with their favorite Linux OS for the sake of portability. So I think this tutorial will be useful to you.

After you power on your PC properly, a splash image will appear within few seconds on your monitor probably mentioning about your motherboard vendor or vendor logo. Some keys and their function may be mentioned on the screen.
For example: F9 : Boot menu F2 : Setup
The keys used for boot setup and boot menu will greatly varied. But the major problem is that this splash screen appears for less than a second in some systems so that you can't even recognize what is written on the screen. Here you should do is that press 'Pause/Break' key in your keyboard (It is positioned in between alphabetic keypad and numeric keypad). Then the screen pauses. Then you can configure as you like it. If you now want to boot system normally, press 'Enter'. Each of the operation will be explained while you are attempting to change this. This will not be explained here because this is different for different systems. But in most systems, if you think that you did something and don't know what is the consequence press 'Esc' continuously and probably one dialog box asks you to save changes. Press n/N for No or y/Y for Yes if you want to save changes.

If you want to just boot from CD ROM or like external devices, good option is that select one resource form the boot menu. The way how to navigate to the boot menu will be specified on the splash screen. If not, try F8 because, many systems having F8 as the boot menu key may not be explicitly shown. In boot menu, you can see several sources. 1.FLOPPY 2.HDD 3. CD-ROM 4.USB HDD .Select one which you want to and press 'Enter'. The system try to boot from the source. If fails, system may try a normal boot or a restart. Sometimes some devices for example USB HDD will not be listed until you inserted your memory stick or pen drive to the system before power up. In this case you should insert the USB device and try a restart and do the same procedure. Similarly, you should insert CD ROM to your drive before selecting boot device. One more thing is that if you are attempting to boot from a pend drive (or memory stick or thumb drive), you should select USB HDD. Some other options like USB FDD, USB ZIP may also be listed. One more problem associated with USB boot is that if you didn't enable USB boot in the boot setup (the key for boot setup will be displayed on splash screen), USB boot will be failure. In some systems you have options to enable/disable USB 2.0. All you need to do is that if a USB boot failure occurs, you should navigate through the boot setup menu and do as your need. In this case, the boot selection will not be saved and need to do the same procedure every time you boot time. Otherwise a normal boot will occur.

To permanently setup a boot configuration, you navigate to the boot setup menu and change the 'boot priority'. In normal case, first boot device will be HDD. You can change it to CD- ROM or USB HDD. One thing be noted is that you should give a priority to HDD as second or third device. Hence, if a boot error occur on the first device, system try on the second device (here HDD), so a normal boot will occur. Change the boot priority to CD-ROM as the first device and second device as HDD is a good practice in order to debug your OS, in case of permanent system crash. Here the system ask to save changes. Press y/Y to say Yes, and this configuration is saved on BIOS for future.

If you do the configuration permanently, every time system checks for first priority device and may feel time consuming if you are waiting for a normal boot. If you are doing it in temporary, every time you need to select boot device. It is recommended that you permanently change boot setup in your Home PC while temporarily do in office PCs.

In the worst case, your motherboard will be entirely different thing and you need o read motherboard users manual. If you didn't got any manual on purchase, you can freely download it from the vendor's website. Probably you need to search by the part number. The part number of your mother board can be found on the top side of your motherboard (Hmmm..Best chance to hack your PC).USB boot is not allowed in some old PCs. But all general purpose motherboards not older than 3 or 4 years can have USB boot capabilities.