Kobo Mini Hack : Increase Storage capacity

I got a Kobo mini two years back for $50, during limited discount sale in USA. I love the reader and use it often. It came with 2GB memory, out of which about 1.3 GB was usable for storing books.While this is enough to hold everything you can read in your lifetime in ePub format, but I still wanted to extend the storage to store more stuff.

Hacking Kobo mini is very easy. Here is what you need.

  1. Kobo mini indeed
  2. A Micro SD card. I used 8GB card.
  3. SD card reader. You cannot insert card in a device and use the Mass storage mode.
  4. Disk imaging software.
  5. Partition extender software.

The steps are very easy.

Disassemble the Kobo mini: After removing the back cover of Kobo Mini, you need to take out the screws.


SD Card : The book reader has SD card in it for storage & the OS for book reader. we need to clone this sd card on a new one.



Cloning and partitioning : Now, you need to do two steps.

1. Clone the Kobo SD card to new card with larger size. Link on how to clone an SD card.

2. Extend the partition using mini partition tool. Link on how to extend tool.

Partition Tool

Partition Tool2

Done! After you are done with cloning and partition extension, insert the new SD card and enjoy.



Hope you enjoyed the hack


Posted in Computers - Software / Hardware, Consumer Products, Electronics Hacks

Part 6 – Retro Gaming : Other important stuff

Linked pages for detailed build information

There are several things that I would like to tell you, that will help your build. or eliminate wastage of time.

  1. Shock hazard: Needless to say, be careful when touching bare wires. 12V may not kill you but it can be nasty.
  2. Build everything first: It makes perfect sense to build your full gaming setup first. that is, put every piece together before you start ripping off the Controller or LCD. Even during the build, build in a way you can keep testing it in between the build.
  3. LCD is delicate: Not only LCD is delicate, it is also very sensitive to over-voltage damage. handle the flex ribbon carefully or it may break. DO NOT power LCD wrongly.
  4. Ripping stuff : Be patient when opening parts. I actually damaged a trace on LCD controller when prying it open. Fortunately, a bodge wire fixed it. But I wasted two days trying to figure out what went wrong.
  5. Gluing stuff: I recommend that you only put spots of glue initially to bind things together. Once everything works, you can put more uniform glue. At the end of your build, you can glue wires so that they don’t move too much. 
  6. Insulation: Although I did not do good job of insulation, its a good idea to use Heat shrink tubing. Or just electrical tape to avoid shorting.
  7. SD card image It is possible that you may need to load image to your SD card again. On windows, it shows incorrect size after you load RetroPie image. And would not allow to reload image. The fix is to use diskpart utility and clear the disk.
  8. Emulator trick : The way emulator is build, that only those emulators show up, which has any file inside the ROMS/<Emulator_Name> folder. By default, it shows X86 DOS, and Apple emulators. Just delete files inside the emulators folder. I kept only NES and deleted the rest.
  9. Use HDMI or TV For configuring the system, use HDMI display/ TV if you have one. Else prefer to use RCA Video. The Small LCD is not good enough for configuration and running Linux commands.

I hope this will be useful to you.


Posted in Raspbeery PI

Part 5 – Retro Gaming : AV, USB and Power connections

Linked pages for detailed build information

This section talks about various connectors of the build.

External USB Connection: The enclosure has a female USB connection exposed. On Raspberry Pi, it is connected to USB Port. This can be used for connecting external keyboard, Additional Controller, Wifi Dongle etc. 

Also, I found interesting thing that the whole system can also be powered using USB. If we connect USB to a power source, it powers the Raspberry Pi. Also, with LCD connected parallel to the Raspberry Pi power, it also gets powered.


In the image below, you can see how the external Female USB wires are directly soldered on the Socket. The duel USB socket onboard the Raspberry Pi has a stell cover. I removed that cover. This allows soldering directly on it. This can also power the Raspberry Pi.


Game Controller: The game controller is connected to the second USB port on Raspbery Pi. In Model Raspberry Pi A, You would need a USB hub if you want additional USB port exposed. But if you only want the game controller, its fine.


Audio Jack: The jack was desoldered from the board. Thus, it reduced the board height. Also, it makes it easy to mount Audio socket on the Enclosure. Connect all the wires as on the board. It also causes and interrupt, which disables Audio on the HDMI, when you connect an audio plug. I plan to add small speakers in the case and then use this interrupt  to switch between the Headphones and Internal speakers.


RCA Video: Like the Audio jack, the RCA socket was desoldered from the board. It has now been connected to the enclosure for using it on normal TV. Also, the interrupt allows us to disable handheld Video when AV cable is attached to a TV.

Also, on the right to the Video socket, you may notice a switch. This acts as On/Off switch for the whole unit.


Power connection: Though not in use now, I plan to use the socket to power the device using a 12V external charger. This will charge the Li-Ion Battery, that I plan to add to the build later on. You may notice it in the picture above, on the right side besides the USB plug.

Future Plans: In future, I plan to add batteries, battery charger and DC to DC inverter to the build.

Posted in Raspbeery PI

Part 4 – Retro Gaming : Controller configuration

Linked pages for detailed build information

I am most interested in NES emulator only. So, I would cover only the NES Setup. Others are very similar.

There are two ways to configure the controller.

  • By running the configuration program.
  • Manually updating the retroarch.cfg file ( Download Link )

If you prefer Video, then refer to MrVestek Youtube blog. Else you can also refer to Adafruit blog ( Link ).

If you are using same controller as I have used, then just copy the file to the Raspberry Pi. ( Link for instruction ). Download the file from Google Link. Here are the mapping of the keys. 


You can directly edit the config file. here is the settings that would work. Note that the Configuration for the Up,Down, Left, Right keys is set as +5, -5, +4 & -4.

# ———————————
# Using the gamepad button for this
input_enable_hotkey_btn = “1″
input_exit_emulator_btn = “5″
# Using the gamepad button for this

input_player1_joypad_index = “0″
input_player1_select_btn = “8″
input_player1_start_btn = “9″
input_player1_y_btn = “2″
input_player1_b_btn = “3″
input_player1_x_btn = “2″
input_player1_a_btn = “0″
input_player1_up_axis = “-5″
input_player1_down_axis = “+5″
input_player1_left_axis = “-4″
input_player1_right_axis = “+4″
input_player1_l_btn = “6″
input_player1_r_btn = “4″
input_screenshot_btn = “0″
screenshot_directory = /home/pi/RetroPie/screenshots
input_save_state_btn = “3″
input_load_state_btn = “2″
input_state_slot_increase_btn = “5″
input_state_slot_decrease_btn = “4″
input_pause_toggle_btn = “1″

# ———————————-

After the configuration is done, try playing some games to ensure configuration is correct.

f you are using some other controller, you can view MrVestek Youtube videos.

Also, I copied the ROM files to the Raspberry pie. you can either copy using USB or directly to the system. ( Link )

The Controller is ready to Play!!!

Posted in Raspbeery PI