SPI Protocol

Introduction to the SPI function The serial peripheral interface (SPI) protocol initially was proposed by Freescale to simplify the interfacing of peripheral devices (ICs) to the microcontroller. Since its introduction, the SPI has been adopted by almost all 8-bit, 16-bit and 32-bit microcontrollers. SPI protocol is used mainly in interfacing with peripheral  devices such as […]

DS1302 communication with an AVR micro

DS1302 is designed to be connected, usually serially, with a microcontroller. It exchanges data based on a specially designed protocol such as the one described above. Below we will present the basic communication steps of DS1302 with an AVR microcontroller. For our convenience, we define the following directives and we place them at the beginning […]

K115 Digital clock and thermometer

Introduction In this tutorial I am going to show you how to make a digital clock with led display of 2.3 inches as well as a temperature display. The clock is one of the most usual devices at home or in the office and a DIY (Do It Yourself) construction will be useful not to […]

DS18B20 communication with an AVR micro

The DS18B20 can communicate with an AVR microcontroller through 1-Wire communication protocol. Several signal types are defined by this protocol: reset pulse, presence pulse, write 0, write 1, read 0, and read 1. The bus master initiates all of these signals, with the exception of the present pulse. Useful definitions Since you will need to […]

DS1302 timekeeping chip

DESCRIPTION The DS1302 trickle-charge timekeeping chip contains a real-time clock/calendar. Also it includes 31 bytes of battery-backed general-purpose static RAM. It communicates with a microprocessor via a simple serial interface. The real-time clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with […]

DS18B20 Digital Thermometer

DESCRIPTION The DS18B20 Digital Thermometer provides 9 to 12–bit centigrade temperature measurements and has an alarm function with nonvolatile user-programmable upper and lower trigger points. The DS18B20 communicates over a 1-Wire bus that by definition requires only one data line (and ground) for communication with a central microprocessor. It has an operating temperature range of […]

The drivers MAX7219 and MAX7221

The MAX7219/MAX7221 are compact common – cathode display drivers that interface microcontrollers to 7 – segment numeric LED displays of up to 8 digits (or 64 individuals LEDs). Included on-chip: A BCD code for data coding which can be enabled or not. The MAX7219/MAX7221 allows the user to select code- B decoding or no-decode for […]

K110 mini weather station

In this project, we are building a board for measuring the temperature, the humidity and the atmospheric pressure with the help of the Arduino nano platform. We measure temperature and atmospheric pressure with the BMP280 sensor, and humidity with the DHT22 sensor. The indications are displaying at nine 7-segments digits. Project description The DHT22 is […]

K105 Digital clock with digital gates

A clock plays a central role in our life, we use the time to plan everything that affects our lives, from work to entertainment. In this project we are building another kind of clock, with simple integrated circuits, which will be very useful hanging on a wall of our house or our office. The clock […]

K100 Electronic little heart

The electronic little heart that we present here is a nice construction of visual effects, easy to construct, which can be given as a gift. It consists of 22 bright red LEDs arranged in heart shape, which are flashing in different combinations giving a pleasant visual effect. Description The circuit of our construction is based […]