Project has been superseeded
Sep 2018 - Ive noticed a few people have starred this project recently, so i wanted to mention that this project is just for legacy and that my other repo is more current / will see development when i get back to it https://github.com/micooke/wwvb_jjy Having said this, you may find that this repo is simpler to understand or that it 'just works'. If so -> awesome!
An Arduino based WWVB transmitter ATtiny85, nano, micro etc., synced off of GPS time (optional). Designed for the 16MHz or 8MHz leonardo or uno
Broken for the ATtiny85 I tried unifying the code for the ATtiny85, ATmega32u4 and ATmega328 series Arduino chips/boards but this implemented a breaking change for the ATtiny85. I assume the reason for this break is an incompatability between the Arduino framework (likely the delay routine) for these chips.
In other words, the library needs to be rewritten for the least useful use case (the ATtiny85). This has a very low priority at the moment, as there is no current need
- Author/s: Mark Cooke, Martin Sniedze
- TimeDateTools.h
- ATtinyGPS.h : for setting time based off a serial GPS
- Equity by La Crosse SkyScan 31269 LCD Atomic Alarm Clock
- La Crosse Technology WS-8418U-IT Atomic Digital Wall Clock with Moon Phase
- BALDR B0114ST - Blue Backlight LCD Atomic Alarm Clock Digital Thermometer Calendar Temperature Table Watch Snooze Timer WWVB Desktop Clock
- Casio Lineage LCW-M170TD-7AJF watch
http://www.nist.gov/pml/div688/grp40/wwvb.cfm
WWVB: 60kHz carrier, Amplitude modulated to Vp -17dB for signal low
Im hoping that the wwvb receiver is insensitive to this -17dB value as im using pulse width modulation to set a 5% duty cycle for the low signal.
See examples folder (start with minimum)