Introduction - If you have any usage issues, please Google them yourself
This program measures the voltage on an external ADC input and prints the
result to a terminal window via the UART.
The system is clocked using the internal 24.5MHz oscillator.
Results are printed to the UART from a loop with the rate set by a delay
based on Timer 2. This loop periodically reads the ADC value from a global
variable, Result.
The ADC makes repeated measurements at a rate determined by SAMPLE_RATE
using Timer 3. The end of each ADC conversion initiates an interrupt which
calls an averaging function.