If you want to build your own word-clock, I recommend the firmware Qlockwork. The source code is very well documented and the functionality of the clock is just great. You can control the clock via Wifi from your mobile phone or tablet. You can set alarms, change colors and configure other settings. The time and alarms are saved in memory even after a power loss if you are using a ds3232. With a DHT22 sensor you can display the temperature and humidity on the clock and on your mobile phone or tablet. I describe in "the easy way" how you can quickly get your personal word-clock.