Understanding internet of things is very important nowadays because it is expanding at the exponential rate. Internet of things provides the facility of interconnecting computing devices, mechanical and digital machines, home accessories, sensors with unique identifier. It has the ability to transfer and receive data from internet by connecting to a network using WIFI. We can also define it as network of physical things and embed it with sensors, software or other technology. In this network a device connects and exchanges data with other devices over the internet.
Applications of internet of things (IoT)
They often divide internet of things into consumer, commercial, industrial and infrastructural spaces. Now let’s take understanding of the different types of internet of things.
They created portion of IoT for consumer use. That includes home automation, connected vehicles, wearable devices, remote sensing devices etc. Using this we can monitor our home accessories, heartbeat rate, blood pressure etc.
Home automation using internet of things (Smart home)
We use a large part of IoT in home automation. Which includes controlling lightings, fan, air conditioning, media, security systems etc over internet from anywhere in the world. We can implement intelligent software or machine learning to save energy by turning home appliances on when it is necessary and turn it off when we no longer need it.
We can control our home appliances which connects to IoT, through our Smartphone by using a dedicated application or Google assistant (Google Home) or Siri.
They created portion of IoT for commercial purpose. That includes medical and healthcare, transportation etc.
Internet of things in Medical and healthcare
The purpose of the IoT in medical and healthcare is to collect data and analyze it for research. It is also used in monitoring purpose. It has been referenced as “Smart healthcare”. IoT can be used to monitor the health of patient including heartbeat rate monitors, blood pressure monitor any many more devices can be embedded.
IoT can help in the transportation also. Nowadays all vehicles have the ability to connect to internet. So we can assist . It can assist in the integration of communication, control and information processing across various transportation systems. We can replace speed-limit sign with IoT digital variable speed-limit sign to vary the speed limit according to traffic, whether etc. We can design an IoT based traffic control, electronic toll collection etc.
Industrial IoT (IIoT) helps monitor and regulate the electronics equipments and industrial systems. IIoT can devices can collect data from connected devices and equipment and analyze them.
In any manufacturing system there can be devices equipped with sensing, identification, communication, actuation and networking capabilities. IoT connects them together and let do their work simultaneously. It also helps to monitor their condition. It enables rapid and smart manufacturing. IoT reduces the manufacturing cost and manpower and thus overall product cost.
IoT plays very important role in the agricultural field such as collecting data about whether, wind speed, humidity, soil moisture etc. By processing these data we can automate the farming. We can use humidity data and soil data to automate the irrigation system and so on. This will reduce farmers effort and improve the quality and quantity of crop.
There can be many more application of IoT and it will be expanding day by day.
Introduction to ESP8266
ESP8266 is a SOC (system on chip) which provides the wifi connectivity feature. Espressif Systems produces this board. It’s design to provide the internet connectivity in small package. Hobbyist and even professional electronics designer use it to design IoT devices using ESP8266. It can connect to the internet, receive and transfer data to other device over internet. By understanding its working and commands we can develop internet of things devices easily. Which we will understand in the next article.
ESP8266 uses standard AT command to communicate to any other microcontroller using USART. AT command is a firmware flashed by manufacturer. Using this AT commands this module connects to any network and sends or receive data. You can reprogram another firmware to directly use it as WIFI enabled microcontroller.
We can add internet connectivity to an Arduino project by connecting this chip using USART. We will be understanding how to connect Arduino to ESP8266 module using USART and develop some internet of things projects in another projects.
Technical specifications of ESP8266
- Manufacturer – Espressif Systems
- CPU – tensilica diamond standard 106 micro
- CPU type – 32 bit microcontroller
- Clock speed (default) – 80 MHz or 160MHz
- Memory – 32KB program data, 80 KB user data
- 802.11 b/ g/ n/ mode + 19.5dBm output power
- Wi-Fi direct (P2P), soft-AP
- Buit-in TCP/ IP protocol stack
- Built-in PLL (phase-locked loop)
- SDIO 2.0, SPI, USART
- Buit-in voltage regulator, power management and power amplifier
- Off leakage current is less than 10mA
- Buit-in TR switch, balun, LNA, matching network
- Support antenna diversity
- Buit-in temperature sensor
- 2ms connect and transfer data packets
- Standby power consumption is less than 1mW.
Board overview: Design, Pinouts and variants
There are many variants of ESP8266 from different vendors and with different breakout boards. Different types of boards differ in number of GPIO pins, amount of memory for storing program and data etc.
The esp8266 board below is the most common board that we use.
This is the most common esp8266 board that we use. This is a cheapest Wi-Fi module. You can get it around 3 dollars. As you can see that this board has some component soldered on it including 2 IC and some small capacitors, inductor and resistors. It has an on board antenna also. We have 8 pins to connect it to any other microcontroller. Let’s see its pin diagram.
Rx pin in the board is used to receive the serial data and Tx pin is used to transmit the serial data. Vcc and GND are used to power the board. This board operates on 3.3v. RESET pin is used to reset the chip. When this pin is low (0) then board is reset. CH_PD is chip power down pin. When it is high then the chip runs normally and when it is low then chip goes in minimum power mode.
Just like Arduino, ESP8266 has two digital input/output pins. We can use those either as input to read a digital voltage or as output to output high or low voltages.