Arduino Master Wall Clock.
Time displayed on large 1″ (26mm) 7 segment displays with secondary 4×20 LCD information display. The clock can be used stand alone or provides the following pulses to drive slave clocks 1 sec alternating, 30 sec, 1 min , 1 hour, 24 hr, 15 min chime of quarter hours, hourly chime of hours.
An Arduino 328 Microprocessor is used to decode and display time & date from the DCF77 “Atomic” Clock in Mainflingen near Frankfurt Germany.
The DCF77 signal is decoded using the fantastic new DCF77 library written by Udo Klein meaning the clock stays in sync and keeps perfect time even with a massive amount of noise on the received DCF77 signal. Udo Klein’s DCF77 library also continually “Auto Tunes” the quartz crystal so in the rare event the signal can’t be decoded the clock remains accurate within 1 sec over many days.
Secondary 4×20 I2C LCD display is used to display time & date, fast or slow seconds, summer winter correction, display brightness, sync information, signal quality, auto tune’d frequency, auto tuned quartz accuracy and summer winter time mode.
The primary and secondary displays are auto dimmed using an LDR and Pulse Width Modulation. The primary and secondary displays are shut down during daytime and are activated by Passive Infrared detection when the clock detects someone entering the room. Manually triggered automatic Summer/Winter time correction of 30 second slave clocks. Blue-Tooth link for programming, clock pulse status and PIR adjusting Auto leap second adjustment of 30 second slave and 1 second slave clocks time and date of leap second can be read via Blue-tooth on your PC or Android mobile or tablet Recording of fast or slow 1 second slave clock pulses on the LCD display as well as time and date stamping of last fast or slow pulse accessible by Bluetooth on your PC or Android mobile or tablet.
See enclosed 4K video of clock pulsing and chiming the hours at 22:00hrs.
For More Details: Arduino DCF77 Master Wall Clock