Arduino

A digital clock is a commonly used electronic gadget. A digital clock keeps track of time and displays the current time through an output device. The users can set or reset the clock using buttons. Electronic clocks are built using microcontrollers and may or may not use a real-time clock. Here, a digital clock is…

In the previous tutorial, we learned how to interface a buzzer with Arduino. A buzzer is an audio signaling output device. Embedded systems are built by interfacing several input and output devices with a controller or computer.  In this tutorial, we’ll interface an input device — specifically, a TTP229 capacitive touch keypad — with Arduino.…

In the previous tutorials, we learned about serial communication using the SPI (serial peripheral interface) and seven-segment multiplexing using the MAX7219 IC. We’ve also covered digital I/O, analog input, PWM (pulse width modulation), and all of the serial communication protocols commonly used by embedded controllers (the UART, I2C, and SPI).  This completes the basic coverage of the Arduino platform. With the above-mentioned skillsets, we…

In the previous tutorial, we learned how to interface a seven-segment display with Arduino. A seven-segment display is comprised of a unit of eight LEDs and seven of which are bar-shape and one is a dot. These display units are ideal for displaying numbers or letters. For example, they’re often used as a display unit…

Usually, the households have post paid electricity connections. On the consumer side, post paid connections have drawback that the consumption of electricity is not tracked by the consumers and many times they are shocked, when they receive high bills. The cause of getting high bills is usually not the high electricity rates but is the unconscious overuse of electricity. Prepaid electricity connections are usually suggested as the viable solution to this problem. In a prepaid electricity connection, consumer would need to recharge the amount of electricity they want to consume.In such a system, the household electricity meters need to be equipped with a system that could be acknowledged of the amount recharged by the consumer and could count down the electricity consumption from the recharged amount to zero. Once the meter reaches zero, the main supply would be automatically cut off and could be resumed only after the next recharge.

A wireless sensor network (WSN) refers to a group of sensors that monitor and record certain physical conditions. It typically consists of:  One central receiver (for monitoring, storage, and controlling) Several wireless sensor nodes   The wireless sensor node is a battery or solar-powered circuit that senses physical quantities. This may include temperature, flow, pressure, soil…

In the previous tutorial, we learned how to interface an ADXL345 accelerometer with Arduino by using the I2C bus. UART, I2C, and SPI are the most common serial communication protocols used in embedded electronics.  UART, a universal asynchronous receiver-transmitter, is used for full-duplex serial communication with a single device. The I2C, an inter-integrated circuit, is a master-slave,…

In the previous tutorial, we covered the I2C bus in Arduino. We also learned about using the wire library to communicate with the Inter-integrated circuit or I2C devices using Arduino boards.  The I2C bus is commonly used by digital sensors. When using this interface, hundreds of slave devices can be connected over just two wires. Each device —…

In the previous tutorial, we learned about serial communication in Arduino using the universal asynchronous receiver-transmitter (UART). We also discussed how Arduino can talk with a computer system using the UART protocol.  The UART is a dedicated circuit that implements serial communication according to its protocol. Arduino boards have one or more UART/USART. These UART/USART interfaces are available through…

In previous tutorials, we’ve covered serial communication using the UART and software serial in Arduino. The universal asynchronous receiver/transmitter (UART), I2C, and SPI are the most commonly used serial interfaces in embedded systems.  UART is useful for full-duplex serial communication with a single device over two wires. The I2C or two-wire interface (TWI) is used for half-duplex…

In the previous article, we learned how to send a message to scroll on a notice board from a smartphone using the Bluetooth application, and how to display the date and time. However, Bluetooth is only adequate for short-distance communication of about 10 meters. But what if it’s necessary to send notifications from a greater…

In the previous tutorial, we learned how to use the applications of the Matrix LED scrolling message boards. This included how to send a message or notice to display on such a board by using a laptop or desktop PC. In this article, we’re going to learn how to send that message from a smartphone…

Remote data-monitoring systems have been widely used in nearly all manufacturing industries for many years and with several benefits. For example, these systems allow for the tracking, recording, and ongoing monitoring of data from different sensors — such as for temperature, pressure, flow, humidity, etc. — in a central control room of a plant.  Various…

This tutorial explains how to automate a hand sanitizer bottle. Sanitizers can be found for use at many public places (and especially recently, given the COVID-19 pandemic). However, each press of the cap leaves behind several types of germs on it. One way to avoid this is to automate the bottle so that users never…

Fading or controlling led brightness using arduino uno and potentiometer/variable resistor is not a very hard task. Arduino predefined libraries made it very easy to fade led with arduino uno. Whats going behind the arduino code predefined commands/instructions at software and at hardware level is important to understand. Students normally start with the pre-written arduino…

In the previous tutorial, we learned how to interface a DHT-11 sensor with Arduino. DHT-11 is a digital sensor that comes integrated with an 8-bit microcontroller. This integrated microcontroller outputs humidity and temperature values in the form of a 40-bit digital data packet.  In the last tutorial, we read the data packet by polling one…

In the previous tutorial, we learned how to interface an LM35 temperature sensor with Arduino. LM35 is an analog sensor that can be interfaced with Arduino’s analog input pin.  In this tutorial, we’ll cover how to interface a DHT-11 sensor with Arduino. DHT-11 is a digital temperature and humidity sensor. It outputs a much more…

Here is a very nice and interesting application of controlling a missile launcher model through a smartphone using an android Bluetooth application. The model of the missile launcher is built using two servo motors. One servo motor (azimuth motor) turns the missile launcher left and right while another servo motor (elevation motor) moves the missile…

In this tutorial i am going to teach you about how to use arduino flow meter to measure the amount of water passing through the water valve. Flow meter is actually a valve. One can control the valve manually and digitally in order to limit the flow of water through the pipe. Normally manual water…

This project is by a final year student of university of liverpool. The project is prototype of a bistatic radar system. Prototype is made using arduino uno and ultrasonic transmitter and receiver. To rotate the ultrasonic transmitter and receiver servo motors are used. Ultrasonic receiver and transmitter are mounted on the top of the servo…