Author - Vivek Kartha

EM-18 RFID Reader Module

Interfacing EM-18 RFID reader with Arduino Uno

Arduino Uno is an opensource physical computing platform based on ATmega328 microcontroller and provides a development environment for writing software for the board. It can be used for a variety of projects. EM-18 RFID reader is one of the commonly used RFID reader to read 125KHz tags. It features low cost, low power consumption, small form factor and easy to use. It provides both UART and Wiegand26 output formats. It can be directly interfaced with microcontrollers using UART and with PC using [...]

Read more...
DS18B20

Interfacing DS18B20 Temperature sensor with Raspberry Pi

DS18B20 is a commonly used temperature temperature sensor providing 9 bit to 12 bit digital Celsius temperature measurements. The sensor communicates over one wire bus. Each sensor has a 64 bit serial code enabling multiple sensors to be connected to the same one wire bus. The Raspberry Pi has drivers for one wired devices to be connected to GPIO pin-4 by default. 1-wire is a device communication data bus system developed by Dallas semiconductor providing low speed data, signalling and [...]

Read more...
Raspberry Pi SSH

Access Raspberry Pi directly from Windows PC

Usually beginners require a display, keyboard and mouse for using Raspberry Pi. But being a linux based system, the Pi can be accessed through a variety of methods like SSH (check our Raspberry Pi SSH tutorial), VNC (check our Raspberry Pi VNC tutorial) etc.. But these methods require an already existing network consisting of a router or other network devices. It would be easier to directly connect the Pi to the computer and work with it without any additional hardwares like router. [...]

Read more...
EM-18 RFID Reader Module

Interfacing EM-18 RFID reader with Raspberry Pi

RFID (Radio Frequency Identification) uses electromagnetic fields to read, monitor and transfer data from tags attached to different objects. It is not necessary that the cards are to be in visibility of the reader, it can be embedded in the tracked object. The tags can be actively powered from a power source or can be passively powered form the incoming electromagnetic fields. EM-18 RFID reader module is one of the commonly used reader and can read any 125KHz tags. It [...]

Read more...
TTL to RS232 Converter

Using UART on Raspberry Pi – Python

UART stands for Universal Asynchronous Transmitter / Receiver, a popular serial communication interface which provides full duplex communication between two devices. The term universal means that transmission speed and data format are configurable. As it is asynchronous it doesn’t need to send clock signal along with the data signals. UART uses two data lines for sending (Tx) and receiving (Rx) data. The ground of both devices should be made common. UART Communication   Freeing up UART pins on Raspberry Pi GPIO By default [...]

Read more...
hc-sr501-pir-motion-sensor

Interfacing HC-SR501 PIR Motion Sensor with Raspberry Pi

All living beings radiate energy to the surroundings in the form of infrared radiations which are invisible to human eyes. A PIR (Passive infrared) sensor can be used to detect these passive radiations. When an object (human or animal) emitting infrared radiations passes through the field of view of the sensor, it detects the change in temperature and therefore can be used to detect motion. HC-SR501 uses differential detection with two pyroelectric infrared sensors. By taking difference of the values, the [...]

Read more...
HC-SR04 Ultrasonic Sensor

Interfacing HC-SR04 Ultrasonic Sensor with Raspberry Pi

HC-SR04 Ultrasonic Sensor Ultrasonic distance sensors are designed to measure distance between the source and target using ultrasonic waves. We use ultrasonic waves because they are relatively accurate across short distances and don’t cause disturbances as they are inaudible to human ear. HC-SR04 is a commonly used module for non contact distance measurement for distances from 2cm to 400cm. It uses sonar (like bats and dolphins) to measure distance with high accuracy and stable readings. It consist of an ultrasonic transmitter, [...]

Read more...
Push Button Switch

Using Switch with Raspberry Pi – Python

I hope that you already go through our tutorial, LED Blinking using Raspberry Pi. Detecting switch status is one of the basic step in learning Raspberry Pi GPIO operations. Here we using Python programming language. I hope that you already installed Python GPIO Library in your Raspberry Pi, if not please follow our first tutorial LED Blinking using Raspberry Pi. Raspberry Pi GPIO Pin Out Raspberry Pi GPIO layout Pull Up and Pull Down Raspberry Pi has internal Pull Up and Pull Down resistors which can [...]

Read more...