Download Bachelor Thesis

3 Execution of the integration
integration
This chapter describes the actual steps that were carried out to successfully integrate
the Raspberry Pi into the WSI system. A step-by-step guide of the setup for practical
use can be found in the clkboard gitviz wiki and is also included in the addendum.
To comply with the WSI system requirements the following steps have to be carried
out:
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setting up an operating system for the Raspberry Pi to be able to run the
clkboard programme;
adapting the pin layout of the Raspberry Pi GPIO header in the kernel to
match the clockboard pin layout (cp. figures 6 and 7);
configuring the interfaces used for the communication with the WSI system;
adapting the clkboard programme from the taskit board to the Raspberry Pi.
(This had to done only once which happened during the work on this thesis.)
3.1 Installation of the operating system Debian
The clkboard programme is laid out to run on top of an operating system, so installing
one on the Raspberry Pi is the first thing to do. The preferred system for this task is
Debian, as there is a distribution available, which is optimised in particular for the
Raspberry Pi. It can be downloaded from
http://www.raspberrypi.org/downloads [16].
For this thesis the “Wheezy 2013-02-09” distribution was used. The operating system
always runs from an SD card, which was found to be reasonable during the
development of the Raspberry Pi. SD cards deliver high capacity, are cheap and fast,
easily writable and easily changeable in case of damage. The link provided below13
contains a table with reportedly working SD cards and read/write speeds.
The size of the used card should amount to at least 4 GB, as it will contain the
operating system (about 2 GB) and should still provide some additional space. The
filesystem used for the first setup during the integration of the Raspberry Pi into the
WSI system was ext4 [17]. It is recommended to continue working with ext4 or at least
another journaling filesystem, as journaling provides higher security in case of a power
failure or a system crash [18]. After unpacking the downloaded Debian image, it can be
copied onto the SD card [19]. (Cf. step-by-step guide for details of the SD card setup.)
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http://elinux.org/RPi_SD_cards [50]