Category Archives: Operating System

Operating system is computer/device software used to organize how the computer work, mainly as base software that build up and connect all the computer hardware with ability to maintenance and organize how other application work.

Kodi video and add-on sound problem raspberry pi2

in previous post ive install kodi on raspberry pi2.
installation was successfull and i can see kodi start screen on my tv. but what about its feature to play any videos (almost format) and music files?

the next step is to try some movie files with different display size, from sd to hd.
all SD file size was played smoothly by kodi. but for 1080p size first i saw lag on video.
to solve this lag problem it is suggested that we change gpu parameter in /boot/config.txt to be larger than 160. just to make sure it is larger than 160 i set it to 512 haha don’t know whether it was necessary or not. alongside with increasing gpu mem i also try menu raspi-config to do the overclocking.

now the bottom of my /boot/config.txt  looks like this



i did the reboot and tried to play the 1080p video file and other video file. Viola there was no lag. But some of the videos didn’t output sound. There was just no output sound.
i tought maybe it was codec problem. so i move to next step. Testing video add-on. and yes, the same problem appeared, all add-on video (display) was playing well, but there was no sound :(. i’ve tried several add-ons such as youtube,, and ted talk.

after some googling i found some posts suggest us to set some options in kodi setting > system > audio output. you can try by yourself. i found my issue was solved by doing this..

Step 1. Testing analogue output

1. setting > system > audio output2. plug your headset/earphone (3.5 mm jack) to your raspberry pi 2
3. back to kodi menu, choose audio output device, change from default PI:HDMI to other output device >> PI:analogue. Don’t forget to adjust kodi volume with your remote :D. set the volume up to make sure it was not reset to minimum volume.
4. the sound shoud’ve came up by now :). now you can listen with your earphone all the time, or output it to speaker (using 3.5 mm jack).

Now what you want is offcourse sound output on you tv (via hdmi).

1. now choose “Audion Output Device” back to original >> PI:HDMI.
2. see if the sound appear, if not now check the “Output Configuration” menu.
3. Change from default “Best Match” to “Fixed”. Check “Limit sampling rate” the default value is “48.0”.
4. “This is”, Now my video that previously didn’t output sound on HDMI audio ouput begin to sound :D. if it still not ouput anything try to change default value “48.0” with other value available in the menu. see if one gives you what you want. dont forget check the kodi volume (via remote) each time you try your configuration.

So far this solution works for me. hope it works for you too

Raspberry pi how to connect raspberry to android phone

After you are able to install and connect you raspberry pi via laptop and lan.
maybe its necesarry for you to connect your rasberry pi via android phone.

here is how

What you need.

1. wifi module
2. access to rasberry pi (via putty or direct).
3. android phone with SSH Client application installed
here is to download SSH Client application

Step by step

1. plug in wifi module to raspberry pi
2. turn on raspberry pi. enter ifconfig command, wlan0 should come up in list, but not connected to any address
pi@raspberrypi ~ $ ifconfig
wlan0     Link encap:Ethernet  HWaddr
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

4. turn on wifi hotspot/tethering on your android phone
5. enter command sudo iwlist wlan0 scan | grep ESSID

pi@raspberrypi ~ $ sudo iwlist wlan0 scan | grep ESSID
ESSID:”HP-Print-41-Officejet Pro 8600″

6. edit wpa_supplicant.conf
sudo nano /etc/wpa_supplicant/wpa_supplicant.conf
add this line

ssid=”your essid name/copy paste from earlier scan result”
psk=”you hotspot password”

for example with my handphone


7. save file, and reboot raspberry pi.
8. after reboot you’ll see that now your raspberry wlan module is connected to you hotspot. enter command sudo ifconfig wlan0 to see its ip address.
9. open SSH client on your android phone and enter raspberry pi address,
10. Now you can access your raspberry via your android phone. :D.

raspberry SSH from android phone
raspberry SSH from android phone

to restart raspberry networking you can enter this command instead rebooting raspberry
sudo /etc/init.d/networking stop
sudo /etc/init.d/networking start

Raspberry pi Recover micro SD space

After installing raspberry pi on my microSD card, i found that my micro SD is not fast enough. if you want to do the test you can go here.

I had to replace my micro SD with another micro SD with bigger capaticy and faster write/read speed. however when i try to re format my micro SD (use it in my android phone). it is displayed that my micro SD size is only 56 Mb, while its capacity is actually 16GB. Where the rest of capacity?

in windows there is disk management tools to manage our partition
(windows logo -> type disk management
or Control Panel\System and Security\Administrative Tools select computer management menu storage click disk management.)

there, my Micro SD (displayed as disk 1) is separated into 2 partition :

56 Mb of FAT partition
14 Gb of unallocated partition

I found out that there is no option to recover unallocated partition via this disk management tool (or is it?).

so i google and got this one

We can use diskpart command via windows cmd. cmd –> type diskpart –> enter, new diskpart window will appear.
2. on diskpart run this command, be carefull, replace “disk 1” with disk name that match your micro SD card.

DISKPART> select disk 1

Disk 1 is now the selected disk.


DiskPart succeeded in cleaning the disk.

DISKPART> create partition primary

DiskPart succeeded in creating the specified partition.


3. after exit, if you open file explorer now micro SD size will display its actual size, right click and format with file format you want to use. mine is FAT32.




SQL exception The last packet successfully received from the server was

i’ve been seeing this SQL exception lately

SQL exception The last packet successfully received from the server was 37,662,089 milliseconds ago. The last packet sent successfully to the server was 37,662,143 milliseconds ago. is longer than the server configured value of ‘wait_timeout’.

on some applications, everytime this exception occured the process is stopped and the transaction is failed.
asking some of my friend who have faced this kind of error before, they recommended to update connector library, they told me that their problem were gone after they did it. but unfortunately it didn’t work for me. so i had to do some googling, and found this one
Solving a “communications link failure” with JDBC and MySQL

in the post itself the writer wrote that there are some solutions that may work, while other may not work for the same SQL Exception message.

for me so far the solution is to use these property

  • validationQuery property
  • AutoReconnect

add this line to our dcbj configuration in context.xml
validationQuery=”SELECT 1″ testOnBorrow=”true”

and modify url by adding “autoReconnect=true”



How find out unidentified device in windows

So it happened yesterday, when i buy new laptop HP Probook 4441s, Unfortunately the online store where i bought this laptop didn’t put in driver software. i had a hard time finding out what software to install to enable my wireless card.

I tried with my laptop hardware specification, but since its sold in some model, i couldnt get any accurate information about the wireless card. actually HP has stored many driver software but, trying it one by one would just waste my time. I better find out it make and model of any hardware in my laptop, then begin searching the right package of driver software to install.

not like ubuntu, i couldnt find any simple step to find out the make and model of unknown device. so i came to google with keyword
how to find wireless card in windows
how to find wireless card chipset in windows
how to see wireless card information in windows,
untill i find really good sites which offers me simple solution with software
the software named unknown device identifier worked really well, in just one click, you can get a resume for any of your hardware attached in your windows laptop

you can go to the page below and download from the source, hope it can help you solve your problem

  • How To See Ubuntu OS 32bit or 64bit

    How To See Ubuntu OS 32bit or 64bit. To determine whether our ubuntu is 32bit or 64bit there is 2 way to check. Accordings to askubuntu we can determine its operating system version by running :

    1. uname -a
    which the results in my computer is

    root@dhcppc12:/sbin# uname -a
    Linux dhcppc12 3.5.0-23-generic #35~precise1-Ubuntu SMP Fri Jan 25 17:15:33 UTC 2013 i686 i686 i386 GNU/Linux

    the bold words shows that it is 32 bit operating system, while it shows you x86_64 x86_64 x86_64
    it means you have installed the 64 bit operating system.

    2. file /sbin/init
    file command is used to determine file type, it will result

    root@dhcppc12:/sbin# file /sbin/init
    /sbin/init: ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.24, BuildID[sha1]=0x07075fcb55b05aeb6286efabba63534fa6ecd213, stripped

    the bold “32-bit” shows you that this file type is 32bit
    it will show you

    ELF 64-bit LSB shared object, x86-64, version 1 (SYS…

    instead if you have installed the 64 bit ubuntu operating system.

    Determining Operating system type is different with determining hardware type.
    to determine hardware type we can use command
    root@dhcppc12:/sbin# lshw -c cpu | grep width
    width: 64 bits
    or simply type lshw -c cpu


    source :

    List of PC Tablet With Docking

    List of PC tablet with docking. Below i write a list of PC Hybrid or PC Tablet Laptop with Docking Station. Other options to attach keyboard to our table exist, such as (non-original) keyboard docking for android and keyboard docking for ipad. But these devices i write below has its original keyboard docking and offers us experience of tablet PC and laptop at the same time.

    1. Asus Transformer Pad
    Asus transformer pad is tablet PC offered by asus. it has eee lines of producst listed in . Asus categorized their product into 3 brands :

    Asus Tablet Product
    • Asus Vivo Tab : Windows 8, 10.1″ display, Intel® Atom™ Z2760 Dual-core, Keyboard Docking
    Asus Vivo Tab
    • Asus Transformer Tab : Android (Ice Cream Sandwich), 10.1″ display NVIDIA® Tegra® 3 T30L Quad-Core @1.2Ghz, Keyboard Docking
    Asus Transformer
    • Asus MemoPad : Android (Jelly bean), 10″ display, NVIDIA Tegra 3 QuadCore, no Keyboard Docking
    Asus Memo Pad

    2. Microsoft Surface
    Microsoft surface is revolutionary new tablet by Microsoft, The Surface comes in two versions: one with Windows RT and another with Windows 8 Pro. The Windows RT model uses an ARM CPU, while the Windows 8 Pro model uses an Intel CPU.

    Surface Pro comes with : Win 7, 10.6″ ClearType Full HD Display, 3rd Gen 1Intel® CoreTM i5 Processor with Intel HD Graphics 4000

    Surface Pro

    Issue with microsoft surface comes with its storage capacity. Its Operating system and applications will need around 32 GB of storage. Leaving amount of harddisk space – 32GB to be used as real storage for files.

    3.HP Envy
    HP Envy X2 is notebook that doubles as tablet. It offers windows 8 experience laptop with bright display and the mobility of tablet. Its main feature are : Windows 8, Intel Atom Processor Z2760 (1.80GHz) + Intel Graphics for 64GB SSD, 11.6-inch display IPS.


    4. Samsung Ativ
    Samsung offers Samsung Ativ smart PC and Samsung Ativ SmartPC Pro. Samsung Ativ SmartPC comes with  : Windows 8, Intel Atom Processor Z2760, 11.6″ Intel Graphic Media Accelerator

    Samsung Ativ

    5. Lenovo IdeaPad
    Lenovo comes up with variety of PC Tablet Product, IdeaPad Yoga is one of its product that offers you 4 mode. Like it said in it website, “Choose from one of four modes to use your Yoga: tablet, laptop, tent or stand. Simply flip and fold
    the touchscreen, then start your journey.”

    Lenovo IdeaPad Yoga

    Yoga 11 with 11.6″ HD display and Yoga 13 with 13.3″ HD IPS Display.
    Those two products is actually called convertible laptop, its keyboards can move almost freely in 360 one axis movement.

    More tablet experience are offered by

    • IdeaTab S2110 : Android 4, 10.1″
    • IdeaTab Lynk : Up to Win 8, 11.6″
    • Thinkpad Tablet 2 : Up to Win 8, 11.6″
    IdeaTab S2110
    IdeaTab Lynk
    ThinkPad Tablet 2

    How To Edit hosts file in Windows

    Editing hosts file in windows

    Host file in windows is used to map ip address into the its name. By using hosts file we can refers any particular IP address by using the name we specified.

    the hosts file contains lines of ip address and its name for example localhost

    so every time we use ‘localhost’ in any networking activities in our laptop, this will be translated into, which is our loopback ip address, ip address belongs to our own laptop/pc/device.

    How to edit hosts file
    editing host file in windows is as simple as adding new lines containing ip address, space, and name we want to refer.

    for example i want to add ip address which i want it be referred by college.
    just add it below the existing line localhost collage office

    the steps :

    1. the hosts file is located in C:/Windows/System32/Drivers/etc/
    it is file with no extension

    2. To open this file, you will need administrator privilege, so you need to open it using any word processor that has administrator privilege confirmed.
    for example we can use notepad, but when we want to run notepad,
    first, do the right click on notepad icon, then choose ‘run as administrator’, choose yes when dialogue appear

    3. in menubar choose File > Open, look for C:\Windows\System32\drivers\etc
    if you don’t see any file, make sure you choose *All File in file type option

    How to edit hosts file in Windows 7
    How to edit hosts file in Windows 7

    4. You will find the hosts file, choose it, and open. Add the ip address and name you want and save those notepad using Ctrl+S.

    Blocking web address using host file

    Other simple use of Hosts file in windows and other operating system is to block web address. This can be done by pointing any web address which is inn their domain name, to our local ip address. for example, we want to block and Then just add in our hosts file

    it will point to, our own ip address. so it will not reach the real and display nothing in the web browser

    How to Enable Copy Paste in Windows Command Prompt

    have you experienced a moment when you use command prompt and it feels not comfortable? if yes, then the answer is maybe because by default we can not do copy paste in windows command prompt. To enable Copy and Paste function in CMD, we just need 3 step.

    1. Open/Run CMD
    2. Right Click in Windows Border, choose properties

    Enable copy paste in Windows Command Prompt
    Enable copy paste in Windows Command Prompt

    3. In new properties window, check the “Quick Edit Mode” and click OK
    Enable copy paste in windows cmd
    Enable copy paste in windows cmd

    Now you can easily copy paste any text in Command Prompt using right click.

    simply do the right click will paste any previous text stored in clipboard.
    while pointing any text by blocking any text will copy the text in cmd to clipboard.

    How to see your windows product key or seriall number

    How to see your windows product key?. How to see your windows 7 serial number? Windows product code once installed, this information will be saved by windows in registry, there is no common utilities provided by windows to look or to view this product key or serial number. However if you want to see this windows product key or you want to see your windows serial number. there are many free programs available to download.

    one of those program is belarc advisor.
    Using this belarc advisor you can get more information that you need. Belarc Advisor will not only provide you your windows (windows 7, vista, xp) product key/serial number. It will also give you any product key from application program that you have installed into your PC.

    It gives you more for less expectation, in fact, it will display our computer profile summary, haha its scary actually because it can reveal our sensitive data such as our windows security update status, any used application in some past days, and any media storage that we had plugged in into our computer

    This is How Belarc Advisor shows me my windows 7 product key

    How to see your windows 7 product key
    How to see your windows product key

    It may take several minutes for belarc advisor to get all of this data, but it is very informative and very easy to use :).

    If you want to see your windows 7 product code / serial code, just Download it here