With this first post we start off on something of an adventure, experimenting and experiencing one of the most fascinating aspects of this SBC (Single Board Computer): connecting the device with the real world.
(note: here we consider working with a Raspberry PI 2 but almost all the mentioned features and possibilities will apply to the previous models).
Connecting the Raspberry PI to Something Else
One of the most interesting features of the Raspberry Pi is that it includes most of the features we need to interact with the real world. Firstly we have the GPIO, which is the array of pins giving the option to interact with the world through many sensors, communication protocols, motors, LEDs and so on.
But that's not all. There is more, and the possibilities go beyond what we can imagine.
Just as a reminder, take a look to the following image:
Seems incredible, the connector we find in this credit-card sized device:
- 40 Pin GPIO (General I/O ports): can be used for powering low consumption devices, connect I2C protocol external components, Input/Output digital signals, SPI (CLK, MISO, MOSI) protocol, TTL Serial TX/RX pins.
- 4 USB2 ports: that means, on a Linux-based system, the possibility to connect a very wide range of USB devices.
- 1 HDMI video and audio output: the HDMI video and audio output supporting full 1080P HD format gives the possibility to manage any display ratio (software configurable) with high quality audio. This feature makes the Raspberry PI a good base machine to make a good quality media center, game device and more.
- 1 combined 4-pole 3.5 mm Jack connector for stereo output and composite video output: ideal when an HDMI monitor is not available.
- 1 10/100 Ethernet RJ45 connector: for LAN connection as an alternative to the wireless WiFi when using a USB WiFi dongle
- 1 camera connector: this connector is ready to work for the Raspberry PI camera that opens the door to an entire world of possibilities, from image shooting up to video capture, streaming, image processing and more.
- 1 display connector: for small projects the use of a full sized external monitor may not be necessary, so a small screen (better if it's a touchscreeb) directly connected to the Raspberry Pi can be a better solution.
When the device is in your hands you have got the keys that open the door to an incredible new world.
All that glitters is not gold
In fact, this board can't do all that much on its own, solve ANY problems, or replace all your computers. But it can do a lot for sure. Looking in-depth at the Raspberry Pi connectors and functions it seems that some "advanced" features are missing. For example, it'd be better if the Ethernet was 1Gb instead 10/100 only, better if the boot was from something different than an SD card, better if there was also an audio input, great if the GPIO also included some manner of analog input, and so forth.
It's true, but the Pi does have the great advantage of stability: many of the apparently missing features are compensated by its extreme versatility and - why not? - our ability to create great projects, including those parts expected but not present. In my personal opinion this SBC remains one of the most complete, versatile and well equipped low-cost devices supporting Linux.
An overview on the next posts
To close this introductory first post on the Raspberry Pi peripherals the following is a list of what you can expect in the forthcoming series.
#2 Setting up the HDMI monitor
Despite the HDMI connector, not all the monitors support the same resolution. And the Raspberry Pi shares its video memory with the rest of the available RAM, so it's useful if you can totally control the display parameters (frequency, resolution, aspect ratio, video memory) simply by changing the operating system display configuration file.
#3 An introductory approach to wired and wireless networking
There are more options than simply plugging the LAN cable in the Ethernet port of the Raspberry PI. In this post we'll see how the Raspberry Pi can be a flexible networking device, acting as bridge, access point, wireless device and more.
#4 The Raspberry Pi camera beyond the webcam limits
Thanks to the power of Python and the specific characteristics of the Pi Camera it's possible to specialise the Raspberry Pi as a video/photo station: shooting, filming, image processing for a lot of possible applications; from photography to security, from stop-motion to the time-lapse filming.
#5 Lirc and IR controller: extending the limits of keyboard and mouse
With a very simple hardware approach we introduce the first non-conventional peripheral connection. Thanks to the Linux lirc library we can use a simplified HID (Human Interface Device) - a TV infrared control - to manage programs, device behaviour, and more.
#6 Enhancing our Pi projects with the Pi touchscreen
We will see how we can setup and integrate in our projects the Raspberry Pi 2.4" touch screen device.
#7 Enhancing our Pi projects with the PiFaceCAD LCD display
When a simple message is sufficient to control the Raspberry Pi behaviour but some control buttons would be useful, the PiFaceCAD (Control and Display) is the ideal device, which can be stacked on our Raspberry Pi for mobile, battery-powered applications.
Bookmark this page and the Ultimate Guide to Getting Started with a Raspberry Pi page to stay tuned to this essential guide to Raspberry Pi peripherals, folks!