Hardware Reference
In-Depth Information
Raspbian was one of the first Linux distributions designed specifically for the Raspb-
ery Pi, and it was based on Debian 7.0, nicknamed “Wheezy.” Thus the Raspberry Pi
version was named with the portmanteau “Raspbian Wheezy.” But online electronics
shop
Adafruit
found that Raspbian Wheezy didn't have some of the features it most
wanted for hacking through the Raspberry Pi's breakout pins, so it decided to create
its own. It's called Occidentalis and is based on Raspbian Wheezy with hardware SPI,
I2C, and WiFi support built in, among other things.
Occidentalis is recommended for those with Linux experience who are interested
in taking full advantage of the hardware. Despite the “for education” aspect, it's
not meant for beginners. That doesn't mean it's useless for kids; rather, it means
that this is a do-it-together sort of project.
Occidentalis is worth mentioning in this topic, because it is intended for use with elec-
tronics. This means that it comes preconfigured in kernel and userspace to access
and control some commonly available sensors and components. This is especially
true if they come from Adafruit. Using Occidentalis will save you some time if you're
attempting
Hack #37
.
As of this writing, the current version of Occidentalis is v0.2, based on Raspbian
Wheezy from August 16, 2012. Version 0.1 includes:
• Firmware updating: Liam McLoughlin (“Hexxeh”) created a tool called
rpi-
updater
to update the Raspberry Pi's firmware. We talk about it in more detail in
Hack #25
.
• I2C and hardware SPI supported and initialized at boot.
• Ready-to-go sshd at first boot: At boot, the ssh keys are generated with a user-
name and password of pi/raspberry on raspberrypi.local.
• Support for WiFi through the Realtek RTL8188CUS USB module, a tiny 802.11b/
g/n WLAN controller, which you can purchase from Adafruit and other vendors
for about $12.
• One-wire support on GPIO 4. See
this GitHub page
.
Version 0.2 includes those features as well as:
• Removed persistent wlan0 entry
• RTC, lm-sensors
• Kernel modules DS1307, AD626 I2C digipots, HMC6352, BMP085, and ADS1015,
which support common sensors, like weather sensors
• Custom PWM/Servo kernel module
