Here is a programmable timer project by Victor. It’s PIC18F4550 based and uses a DS1307 real time clock chip to keep time. A small 12 volt relay acts as the switch. [via]
This project, like others before, has started out of need: our 30+ year old mechanical timer for the central heater of the house has finally given it up. It would have been faster and cheaper to get a replacement from the local hardware store, but I decided to learn something new and I set out to create a digital version of it.
Programmable timer switch - [Link]
An Arduino-based clock with 180 RGB LEDs. The LEDs are driven via 12 TLC5925 1- channel constant-current addressable drivers – [via]
Its built on doublesided copper clad board using Toner transfer method. The routes aren’t smaller than 0.44mm and all vias are made for 0.8mm drilling (truly DIY). Just around 5 vias are under a component and 7 segment displays have singnals only from bottom side (for easy soldering)
- 180 RGB LEDs driven by TLC5925 constant current LED drivers
- each LED addressed separately (12x TLC5925 with 16 outputs each)
- each colour adressed individually
- 4x 7 segment LED display
- Atmega328P as MCU
- DS1307 real time clock
- Photoresistor (for adjusting brightness)
- And DHT11 for temperature and humidity
- Backup battery for clock
- 5V DC (eg USB)
Clock with 180 RGB LEDs on home-etched circuit board - [Link]
A friend of mine asked me to design a home automation for him. He wants me to build something that will communicate with his air condition through an IR receiver that it has, and it will act as a programmable timer, to turn it on and off automatically. Then i thought that i should spice it up a little bit, and make a programmable IR universal timer, or something. No matter what, i will certainly need to interface an RTC (stands for Real Time Clock) chip. This chip is responsible for keeping the time.
LCD PIC Clock with the Maxim DS1307 RTC - [Link]
Here is my experiment with i2c bus for interfacing serial EEPROM (24C256) and RTC (DS1307) using AVR microcontroller ATmega128. The circuit is also provided with an RS232 port for connecting with PC to send commands for reading/writing EEPROM or setting date/time in RTC (Click on images to enlarge them).
Interfacing RTC & serial EEPROM using i2c bus, with ATmega128 uC – [Link]
I have been busying myself recently with some experiments into programming the Arduino prototyping platform.
I have already created some hardware, a Maxim DS1307 Real Time Clock shield and a Serially Interfaced, 8 digit 7 Segment Display based on a MAX7221 IC. So far I have created test routines to test my hardware but I wanted to really get my teeth into creating some more practical code.
And here it is, A more or less functioning LED clock.
Arduino Cloc: A Maxim DS1307/MAX7221 Based Clock – [Link]
In honor of the new chronodot, we’ve put the brains behind the chip (The maxim DS3231) into our partfinder! This is a high precision ‘big brother’ to the DS1307. It has a built in temperature compensated oscillator so that its very precise. They are a bit chunky but good when you want to really keep track of time and cant integrate a GPS module.
DS3231 – High precision real time clock with built in oscillator – [Link]
This is an Arduino powered 24-hour digital clock that uses the RTC chip DS1307 for timekeeping. DS1307 has a small battery backup so that it keeps the correct time even the rest of the circuit is not powered. The time is displayed on 5×7 LED dot matrix. [via]
Arduino: 24 hours digital clock – [Link]