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 an...
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 power...
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...
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 features...
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...
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 average...
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,...
