Note: Please vote and add comments
Introduction
In this article, we will talk about what Raspberry Pi is, the different types of boards available and then get up close with the various components on the Raspberry Pi board.
Background
Raspberry Pi - the small incredible computer has gained popularity not just because on its size and prize ($35), but because of it capabilities. It's an incredible credit card size board capable of running a full Operating System (OS) and you can connect electronics / devices to it and program them.
Getting Started
Hello!!! Raspberry Pi
The Raspberry Pi is a tiny computer (size of a credit card) designed and developed in the UK. This tiny computer enables everyone (big or small) to learn physical computing, explore basic electronics and learn how to program (programming). The main reason behind developing Raspberry Pi was to teach children’s about physical computing, make them understand how computers work and make them interested in programming.
It’s a computer - you can do almost anything with a Raspberry Pi, as you would with a normal computer. You can play music, browse the Internet, run applications, write programs using languages like Scratch, Python or C# etc. The Raspberry Pi is capable of running a full Operating System. There are different OS (Windows, MAC, Linux version) that can be installed and run on a Raspberry Pi, the recommended OS is a Linux flavor OS called Raspbian (by Raspberry foundation maker of Raspberry).
As mentioned above the size of Raspberry Pi is of a credit card, it a single board that has a Broadcom processor (SOC – system on chip) made by ARM, it’s similar to the processors that is found on mobile phone. The ARM processor is fast and light weight. The Raspberry pi does not have its own Hard Disk, keyboard, Mouse and Monitor.
Hard Disk - Raspberry Pi does not has its own hard disk, you will need to use micro SD cards in place of the Hard disk, and the OS will be installed on these micro SD cards. (Minimum 2 GB micro SD cards is recommended for installing the OS and running normal functionality on the Raspberry Pi). The benefit of using micro SD card is you can easily swap this computer (Raspberry pi) with different OS's on different SD cards. There is a micro SD card slot at the underside / bottom of the Pi board
For Monitor, Key board and Mouse – You can connect the Raspberry Pi via the HDMI port to a monitor (you may need an HDMI to VGA connector to connect to the monitor) and connect the keyboard and the mouse using the USB ports on it. The Raspberry is powered up using a micro USB connection and a power adapter of 5 volt output (adapter used in mobile phones and tablets). It also has built in Ethernet connection to connect to connect to the Internet. (Note: It is recommended to use a powered USB hub to power all the USB devices like keyboard and mouse etc. because powering (connecting) these devices directly to the Raspberry Pi would leave the Pi underpowered, leading to shorter component life and even nonfunctioning Pi.)
The Raspberry Pi is also has bunch of GPIO (General Purpose Input Output) pins that are open / exposed, so that we can use it to build circuits using sensors. The GPIO pins are easy to configure and control and you can write program to read the sensor data coming from the GPIO pins and send back data to the GPIOs pins after processing.
Currently there are six different boards of Raspberry pi available in the Market of which 4 are available for purchase in the open market.
You can purchase these boards as an individual or as part of Startup kits (recommended for beginners). Startup Kits contain the Raspberry Pi board, 8 GB SD card with pre- installed OS, Raspberry Pi Case, power cables, Breadboard, Wi-Fi dongle and other most essential items like the sensors (Temperature, Color, light etc.), jumper cables, capacitor, resistors, LED’s (red, blue and Green), push buttons etc. These startup kits are best way to start doing some popular IOT projects.
Note: I would recommend a starter kit from Adafruit the Microsoft IoT kit. (https://www.adafruit.com/products/2733)
Below are the four raspberry boards for reference.
- Raspberry Pi Zero:
- Dimensions : 65mm x 30mm x 5mm
- Weight : 9g
- Price: less than $10
The Pi Zero has a Broadcom BCM2835, 1GHz ARM11 core CPU and 512 MB RAM, making it powerful enough to handle small tech projects. It has all the functionality that most Pi’s have to offer. The Pi Zero board is much smaller compared to the new version boards (Model A and Model B devices). The Pi Zero board is featured with a micro SD card slot, a mini HDMI socket for video, a micro USB socket for data and power and an unpopulated 40 pins GPIO header( similar to Model A+/B+/2B).
- Raspberry pi 1 Model A+:
- Dimensions :65mm x 56mm
- Weight : 23g
- Price: Around $20
The Raspberry Pi Model A+ was released by the Raspberry foundation in the Year 2014. It has a Broadcom BCM2835, 700MHz Core CPU and 256 MB RAM. The Pi A+ board is featured with a micro SD card slot, a 4 pole Stereo output and Composite video port, full size HDMI socket, CSI camera port (Raspberry Pi camera module), DSI display port (Raspberry Pi touch screen display), Micro USB power connector for power, 4 mounting holes and an 40 pins extended GPIO header
- Raspberry Pi 2 Model B:
- Dimensions :85.60mm × 56.5mm
- Weight : 45g (1.6 oz)
- Price:$35
The Raspberry Pi 2 Model B was released by the Raspberry Pi foundation in 2015, it was a replacement for Model B+ released in Feb 2014. The major changes were the processor and the RAM. It has the Broadcom BCM2836 SOC - System on Chip (CPU, GPU, DSP, and SD RAM), 900MHz quad-core ARM Cortex-A7 CPU and 1 GB RAM. The Pi 2 Model B board is featured with a MicroSD card slot, Video / audio HDMI 1.3 and 1.4, HD 1080p video output, Composite video output (PAL / NTSC), Stereo audio output, Ethernet port 10/100 Base T RJ45, 4 USB 2.0 ports, 15-pin MPI CSI-2 connector for Raspberry Pi HD Video Camera, 15-pin serial display interface connector, Power supply: +5 V @ 2 A via micro USB jack, 40-pin connector for GPIO and serial buses
- . Raspberry Pi 3 Model B:
- Dimensions :85.60mm × 56.5mm
- Weight : 45g (1.6 oz)
- Price:$35 Price hasn't changed
The Raspberry Pi 3 Model B is the latest of the Raspberry Pi boards and was released by the Raspberry Pi foundation in March 2016. I has the improved performance, connectivity, and power management with a 64- bit CPU and onboard Wi-Fi and Bluetooth. It has size similar to the B+ and Pi 2. The Pi 3 Model B board is featured with a MicroSD card slot, It has the Quad core 1.2GHz Broadcom BCM2837 CPU (64-bit ARM Cortex A53) and 1 GB RAM, It has the BCM43143 Wi-Fi (802.11n), Bluetooth Low Energy (BLE), 40-pin connector for GPIO, 4 USB 2.0 ports, CSI camera port, DSI display port, MicroSD card slot, HDMI, 4 pole stereo and composite video port, Upgraded Switched power source up to 2.4A. The performance of the Pi 3 is roughly 50-60% faster than the Pi 2 which means it is ten times faster than the original Pi.
Now that we have seen what Raspberry Pi is and discussed the different models available in Market for purchase. Lets’ now deep dive into a Raspberry Pi and discuss the anatomy of Raspberry Pi. Below is picture of Raspberry Pi 2 Model B.
Anatomy of Raspberry Pi
- DSI: The Display Interface (DSI) - is used to connect the display directly to the Raspberry Pi board.
- GPIO Pins: These are 40 GPIO (General Purpose Input Output) pins, these pins can be directly accessed on the Raspberry Pi. These are used in projects to connect the Raspberry Pi to electronic circuits, sensors and control them. These pins can be turned on or off based on the requirement when the Raspberry is running.
- ARM Processor: It's the heart of the Raspberry Pi, the Broadcom BCM2835 900MHz quad-core ARM Cortex-A7 CPU with 1GB RAM.
- USB Ports: The USB (Universal Serial Bus) ports are used to connect the standard accessories such as keyboard, mouse, Wi-Fi adapter etc. It has 4 USB ports. (It is recommended to use a powered USB hub to power all the USB devices like keyboard and mouse etc. because powering (connecting) these devices directly to the Raspberry Pi would leave the Pi underpowered, leading to shorter component life and even nonfunctioning Pi.)
- Ethernet Connection: you can connect the Pi to a network or home modem / router using an Ethernet cable and this connection. The Raspberry Pi 2 Model B does not have a built in Wi-Fi, but you can add an USB Wi-Fi adapter to the USB port.
- 3.5 MM Audio/Video Jack: This 3.5 mm audio jack is normally used to attach headphones or speakers. On the Raspberry Pi2 it also carries composite video using a compatible cable.
- CSI (Camera Serial Interface): This interface is used to attach the Raspberry P1 Camera module directly to the motherboard via a CSI connection.
- HDMI: The HDMI connection enables you to hook up the Raspberry Pi to the most modern Monitors and digital Televisions. It carries both the video and audio. (Note: in case you have old monitors having VGA port - you would need a HDMI to VGA port adapter to hook up your Raspberry Pi to the old monitor)
- USB Power: This port is used to power on the Pi. A standard Micro USB power supply is used on the Raspberry Pi. You can also use a 5V 2000mA Micro USB power supply and compatible cable to power up the Pi.
- Mini SD Card Slot: The Raspberry Pi does not have a Secondary storage, you need to use mini SD cards to store data and OS. These SD cards with OS need be inserted into the SD card slot before powering up the Pi.
In the Next article we will talk about the difference in each of the Raspberry Pi model and the Pros and Cons
Hope this helps. Please vote or add comments.
