Alarm clocks usually – ring a pair of bells, play jarring noise, imitate the cock a doodle do of a rooster what else? We have seen alarm clocks with radios, and Phones with alarm clocks but most of them [if not all] uses sound to wake you up – not really the most gentle way of waking someone up. What do we recommend?
The sunrise clock – instead of breaking your morning with a bunch of rings that also scares away a good start for your day this clock illuminates the surroundings giving a feel of morning sunrise in the comfort of your own room [yeap rain or shine]. Its build is quite straight forward – time was kept using a real time clock implemented using a STM32F100RB Arm Cortex M3 processor and a ceramic oscillator. Time is displayed using a pair of 8×8 LED matrices. The lamp [the source of light] is controlled using a dimmer circuit composed of an opto-diac and a triac – the opto – diac isolates the microcontroller from the high voltage AC source needed for the lamp while the triac controls how much of the AC wave is used to drive the lamp thus controlling the brightness. The clock also has ambient light detection which utilizes a photoresistor and an ADC channel in the STM32F100RB. Push buttons are used to adjust time, input alarm time and the duration of the lamps lighting. And when all else fail? It has a back up piezoelectric speaker to break eardrums!