Summary of Arduino DCF77 Master Wall Clock
This Arduino Master Wall Clock uses a 328 microprocessor to decode DCF77 atomic signals for precise timekeeping. It features large 1-inch 7-segment displays and a secondary 4x20 LCD screen, both with auto-dimming and motion-activated lighting. The system supports multiple slave clock pulses, Bluetooth programming, and automatic daylight saving adjustments.
Parts used in the Arduino Master Wall Clock:
- Arduino 328 Microprocessor
- Large 1 inch (26mm) 7 segment displays
- Secondary 4x20 I2C LCD display
- DCF77 receiver signal decoder
- LDR (Light Dependent Resistor)
- Passive Infrared (PIR) detector
- Bluetooth module
- Udo Klein's DCF77 library
- Pulse Width Modulation circuitry
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
- How does the clock maintain accurate time without a signal?
The Udo Klein DCF77 library continually auto tunes the quartz crystal to keep the clock accurate within 1 second over many days even if the signal cannot be decoded. - Can this clock drive external slave clocks?
Yes, it provides pulses to drive slave clocks including 1 sec alternating, 30 sec, 1 min, 1 hour, 24 hr, and chime options for quarter hours and hourly chimes. - What information is displayed on the secondary LCD screen?
The secondary 4x20 LCD displays time, date, fast or slow seconds, summer winter correction, display brightness, sync information, signal quality, and auto tuned frequency. - How are the displays managed during the day?
The primary and secondary displays are shut down during daytime using an LDR and are activated by Passive Infrared detection when someone enters the room. - Is there a way to adjust summer and winter time automatically?
The clock offers manually triggered automatic Summer/Winter time correction specifically for 30 second slave clocks. - Can users program the clock remotely?
Yes, a Blue-Tooth link allows for programming, checking clock pulse status, adjusting PIR settings, and reading leap second data via PC or mobile devices. - Does the clock record pulse timing errors?
The system records fast or slow 1 second slave clock pulses on the LCD display with time and date stamping accessible via Bluetooth. - What library is used to decode the atomic clock signal?
The project uses the fantastic new DCF77 library written by Udo Klein which handles noise and auto tuning effectively.
