Wall Clock example using the segment LCD.

This example project uses the EFM32 CMSIS  and demonstrates  the use of 
the LCD controller, RTC (real time counter), VCMP, GPIO and various 
Energy Modes (EM).

The RTC is set up to wake the EFM32 from EM2 every minute. During this 
interval, the LCD is updated to reflect the current time. The animation 
feature is used to show the seconds. This is done by using the frame 
event counter to drive the animation feature every second.

The VCMP is used to measure the input voltage on every wakeup. If the 
voltage drops too low, voltage boost is enabled on the LCD. This makes 
the LCD clear and readable even when running on low batteries.

Board:  Silicon Labs EFM32TG_STK2100 Development Kit
Device: EFM32TG840F32 with LCD 
