First Impressions on the Raspberry Pi

Hi again! A few days ago I made a post about the Raspberry Pi board that I recently got in the mail. I only made a short description of the board since I hadn’t test it at the time. I still haven’t much to say but I have finally tested it and I’ll share my first impressions of the board.

Raspberry Pi desktop
So.. the first thing to do was to download the image of the Debian Squeeze distribution here and set it up in a SD card. The SD card that I used was a Class 4 4GB Emtec card and it although I got some strange errors in the boot process, it worked (from what I’ve read it may be related with the quality of the card). The process that I used to setup the SD card was the following (see the full guides for Windows, Linux and Mac here):

  1. Download the zip file containing the image from a mirror or torrent from here:
  2. Verify if the the hash key of the zip file is the same as shown on the downloads page (optional). Assuming that you put the zip file in your home directory (~/), in the terminal run:
    sha1sum ~/

    This will print out a long hex number which should match the “SHA-1” line for the SD image you have downloaded

  3. Extract the image, with
    unzip ~/
  4. Run df to see what devices are currently mounted
  5. Connect the SD card reader with the SD card inside
  6. Run df again. The device that wasn’t there last time is your SD card. The left column gives the device name of your SD card. It will be listed as something like “/dev/mmcblk0p1” or “/dev/sdd1”. The last part (“p1” or “1” respectively) is the partition number, but you want to write to the whole SD card, not just one partition, so you need to remove that part from the name (getting for example “/dev/mmcblk0” or “/dev/sdd”) as the device for the whole SD card. Note that the SD card can show up more than once in the output of df: in fact it will if you have previously written a Raspberry Pi image to this SD card, because the RPi SD images have more than one partition.
  7. Now that you’ve noted what the device name is, you need to unmount it so that files can’t be read or written to the SD card while you are copying over the SD image. So run the command below, replacing “/dev/sdd1” with whatever your SD card’s device name is (including the partition number)

    umount /dev/sdd1

    If your SD card shows up more than once in the output of df due to having multiple partitions on the SD card, you should unmount all of these partitions.

  8. In the terminal write the image to the card with this command, making sure you replace the input file if= argument with the path to your .img file, and the “/dev/sdd” in the output file of= argument with the right device name (this is very important: you can trash the hard drive on your computer if you get the wrong device name). Make sure the device name is the name of the whole SD card as described above, not just a partition of it (for example, sdd, not sdds1 or sddp1, or mmcblk0 not mmcblk0p1)
    dd bs=1M if=~/debian6-19-04-2012/debian6-19-04-2012.img of=/dev/sdd

    Note that if you are not logged in as root you will need to prefix this with sudo.

  9. Remove SD card from card reader, insert it in the Raspberry Pi, and have fun. 🙂
After setting up the card I inserted it in the SD card socket, connected the HDMI cable and powered it with my cell phone charger (5V 0.7A; I’ve read somewhere that 0.7A is the minimum recommended) and there was Raspberry Pi printing boot stuff on my LCD 😀 After one and a half minute of booting, it went into CLI mode and asked for the username (pi) and password (raspberry). Since I wanted to get into graphical mode I just typed “startx” and it started the LXDE graphical interface. One of the first things that I had to do was to change the locale to get portuguese keyboard layout. To change the locale I opened a terminal and entered:
sudo nano /etc/default/keyboard
Then I had to search for uk type, change it to pt, save and exit. After that I entered the following command in terminal:
sudo dpkg-reconfigure locales
Then I had to choose the locale that I needed (pt_PT) and reboot the RasPi.
The speed of the operating system is pretty acceptable and although it takes some time to open some programs it surprised me in a positive way since I was expecting worse performance considering the specifications of the RasPi. The development IDE’s that come bundled in the Debian Squeeze image take some time to open but operate normally after that. I also tried Scratch and it opened fast enough and ran almost as well as in my laptop 😀
After this short first test I’m very satisfied and I surely think that the RasPi is a very well planned and designed board that will surely change the world. Although it was designed with education in mind, it not only fulfills all the requirements to achieve its objectives in that matter but also can be used in other areas such as electronics, robotics, networks, etc.
As a final comment, get one as soon as you can 😉 You won’t regret and you’ll be helping the Raspberry Pi foundation to improve the education of thousands of kids around the world. Thumbs up for them and thumbs up for the developers of RasPi!
Raspberry Pi and SD card

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