Example Description

This example describes how to use UART TX to simulate clock source

Required Components:
    Oscilloscope

UART0 pin mappings used in this test demo:
            PA18(TX)
            PA19(RX)

Connect the TX pin of UART0 with the oscilloscope, and 
we can watch the clock source waveform we want to generate.

This example shows: 
1. Clock signal output from UART1_TX to oscilloscope
