Dilshan R Jayakody’s Web Log

The main objective of this project is to design a maintenance free and low-cost light which automatically turns on and off at the predetermined time of the day. To meet the above requirement I designed this controller using ATmega8 MCU and DS1307 RTC. The driver stage of this light controller is intended to work with commonly available 7W LED modules. PCB of the programmable light controller. The core component of this programmable light is ATmega8 low power CMOS microcontroller. The main reason to select this microcontroller is it’s lower cost and higher availability. Except for the above two reasons this microcontroller also bundled with a rich set of peripherals which including 23 GPIOs, 3 independent timers, Two-wire serial interface, EEPROM, etc. Apart from ATmega8 microcontroller, this system uses DS1307 real time clock to maintain system time. Like ATmega8, DS1307 is also a very popular RTC in the market. This controller is designed to work with a 24V DC power supp...

Recently I build my new house near Maharagama town. While building this house I allocate space for my antennas and observation equipment. Before installing antennas, I decided to install a lightning rod into the house. The main reason to install a lightning rod is because of the height of the building. It nearly 48 feet (approximately 15m) high, and located in open space, because of those reasons there is a very high probability to hit lightning into my antennas and other equipment. Installed lightning rod At the time of this writing, in here in Sri Lanka mainly two types of lightning arrestor systems are in use. The first type is a conventional lightning rod . This type of lightning rod is very common in Sri Lanka and it made with copper rods. The second type is ESE ( Early Streamer Emission ) type lighting arrestor. This ESE type is now getting popular in here and I saw it in a couple of new buildings. As I noticed most of the lightning arrestor installation companies are ...

This is TCS230 based Bluetooth color picker prototype which we build to test the concept. In here the idea is to extract color from any physical object and transfer it to PC / mobile. To test this concept, we use low-cost TCS230 color sensor. A prototype version of color picker on a tiny breadboard. TCS230 is programmable color light-to-frequency convert IC. This chip produces square wave output with frequency directly proportional to the light intensity. To drive this sensor and capture its output we used PIC16F628A microcontroller. The processed output is then transferred to the host using the HC-05 Bluetooth SPP ( Serial Port Protocol ) module. In PC we wrote small Python script to display captured value and color in a Window. In this design, we drive the TCS230 sensor with 20% frequency scaling. The entire circuit is built using commonly available modules and components. For the color sensor, we use the 8-pin TCS230 sensor module which is commonly found in eBay and other...