Hello, friends welcome to IoTGyaan.com, in this post we are going to tell you about what is raspberry pi, features of raspberry pi, It’s Components, and Add on boards Sense HAT.
Table of Contents
Raspberry Pi and Sense HAT
What is a Raspberry pi?
Raspberry Pi is a very small-sized computer originally designed for education, inspired by the 1981 BBC Micro. Creator Eben Upton’s goal was to create a low-cost device pre-university level.
- Raspberry Pi is a single-board computer that runs the Linux Operating System.
- Raspberry Pi is based on a Broadcom SoC (System of Chip) with an ARM processor [~700 MHz], a GPU, and 256 to 512 MB RAM.
- The cost of a Pi is around $35 for a B Model and is available through many online and physical stores.
Raspberry Pi multiple Models
- Models of R-Pi
- R-Pi Model A+
- R-Pi Model B+
- R-Pi 2
- R-Pi 3
- R-Pi Zero
Contains:
- USB Sockets – Keyboard + Mouse can be plug
- HDMI video output – To connect the monitor
- Camera Connector
- Micro–SD Cardholder
- etc
Although there are a lot of Development Boards that are available in the market at varied prices but Raspberry Pi is supposedly the most suited to start learning the Internet of Things.
Also Read: Sensors For The IoT Device | Types of IoT Sensors
Features of Raspberry Pi
It is useful for small or home-based businesses and is perfect for adaptive technology.
Raspberry Pi can be coded in Python therefore does not require the user to have extensive programming experience since Python is less complex than other languages.
The product is energy efficient and provides an alternative to small businesses.
You are not required to purchase any special license and therefore you can automate several tasks therefore the product also gives you a lot of room to experiment and turn it into something else that is entirely different.
Raspberry Pi and Its Components
1. Processor
- Board uses, – Broadcom BCM2835 / BCM2836 / BCM2837 processor.
- All runs between 700 Mhz – 1.4 GHz.
- Based on ARMv6, ARMv7, ARMv8 and ARMv11 processor cores.
2. Memory
- SDRAM
- Varies from 256 MB – 1 GB
- Memory is shared between CPU & GPU
3. Storage
- Micro-SD card.
- All R-Pi boards boots from micro-SD or SD card.
- Has onboard eMMC, which is effectively an SD card on Chip.
- Uses a friction-fit slot rather than a click-in and click-out slot.
4. Power
- Micro-USB connector.
- A 5V supply is required that should ideally deliver a current of at least 1.1A and ideally 2.5A for the R-pi 3 boards.
- Overcurrent protection is present on this input.
5. Video Out: HDMI
- HDMI / Mini HDMI connector.
- The Raspberry Pi has an HDMI port which you can connect directly to a monitor or TV with an HDMI cable.
- Some modern monitors and TVs have HDMI ports, some do not, but there are other options.
- DVI
- For monitors with a DVI port, you can use an HDMI-to-DVI cable, or an HDMI cable with a DVI adapter.
- The DVI standard does not support any audio.
- VGA
- For monitors with VGA only, you can use an HDMI-to-VGA adapter.
Note that VGA does not support audio.
6. Raspberry pi GPIO pinout: 40 Pins
26x GPIO’s
- General-purpose input/output (GPIO) for reading & writing the binary data.
- All GPIO’s are 3.3V tolerant.
2x I2C buses
- Several devices can be connected via these 2 buses.
SPI bus
- Provides serial synchronous data link over a short distance.
- Master / Slave configurations.
- Requires 4 wires for communications.
UART
- Used for serial communication between two devices.
PWM
- At least one hardware PWM on all devices.
- More than one in recent devices.
GPCLK
- Allows to establish the accurate timings signals.
7. USB Hub
- USB connectors
- R-Pi 3 has five USB ports, among which one is used for ethernet connect.
- The remaining 4 are available for the external connection.
8. Reset Button
- Use to reset the board
9. Audio + Video
- 4- pole 3.5mm jacket.
- Provides composite video and stereo sound on newer cards.
10. Power LED
- Indicates the board is in power-on mode.
- Not present in R-Pi zero.
11. Activity LED
- Indicates that there is some activity going on the board.
- For instance, the led flashes upon inserting the SD card.
12. USB – Ethernet
- SMSC LAN9514
- This IC provides a USB 2.0 hub.
- 10 / 100 Ethernet controller.
- The board connected to the internet via USB rather than onboard ethernet controller within SoC
13. Network
- RJ-45 Ethernet.
- 10/100 Mbps via RJ-45.
- Has onboard wi-fi and Bluetooth.
14. Camera
- Has MIPI-CSI (Mobile Industry Processor Interface with Camera Serial Interface), a 15-pin connector that can be connected to a special purpose camera.
15. Display (DSI)
- A display serial interface is an interface used by mobile phone vendors to interface to a screen display.
- For instance, 7th R-Pi touchscreen (800 x 480 pixels)
Raspberry Pi Add on Boards Sense HAT
Hardware Attached on Top – HATs
- A Hardware Attached on Top or HAT is an Add on Board that can be attached directly over the Raspberry Pi GPIO pins and enhances the capability of the Pi.
- These add on boards are loaded with various features in a single place and when these boards are attached to a processing unit such as Raspberry Pi a very effective solution is generated.
- Some major advantages of using HATs are No Soldering, Robust Mechanical Design, Auto Configuration.
Working of Sense HATs for Raspberry Pi
The HAT should start working as soon as it is connected. The HAT must contain an EEPROM which details the hardware contained on the board.
The Raspberry Pi achieves this by using two specific GPIO pins found on models A +, B + and 2, ID_SD and ID_SC, pins number 27, and 28.
These pins are reserved for connection to an EEPROM (programmable electrically erasable read-only memory) chip on the HAT.
The EEPROM chip contains code in a .dtf file, called a “device tree”, which describes all of the chips and hardware is attached.
When a HAT is connected to a Raspberry Pi, the Pi detects it, reads the .dtf file, and discovers the connected hardware.
Raspbian then automatically loads the drivers required for the hardware, configures the GPIO pins accordingly and the HAT is ready to use.
This allows the Pi to identify a connected HAT and automatically configure the GPIO’s pinout and drivers for the board. HATs were first introduced in 2014 with the Pi model.
Since then, there have been incredible and wonderful HATs, such as The Unicorn HAT, Piano HAT, Sense HAT, and Explorer HAT.
Sense HAT
The Sense HAT is an expansion card for Raspberry Pi, specially designed for the Astro Pi mission – it was launched on the International Space Station in December 2015.
The Sense HAT has an 8 × 8 RGB LED matrix display, a five-button joystick and includes the following sensors:
Configuring Raspberry Pi with Sense HAT
An important feature of HATs is the inclusion of a system that allows the B + to identify a connected HAT and automatically configure the GPIO’s and drivers for the board, making life easier for the end-user. Simply place the Sense HAT on Pi and fix it with screws.
So, we have finally discussed our topics which are – what is raspberry pi, features of raspberry pi, It’s Components, and Add on boards Sense HAT.
So, there is all about the raspberry pi and sense HAT which we need to know. We hope you get a clear understanding of everything in this article. If you want to ask anything, please feel free to contact us by commenting down below.
Also Read: Beginner’s Guide to Understand the Internet of Things
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