================================================================================
                                样例使用说明
                             Sample Description
================================================================================
功能描述：
此样例演示了ADC的Vrefint功能，通过Vrefint的值，可以反推出MCU的供电电压值。

Function descriptions:
This example demonstrates the Vrefint function of ADC. By using the value of
Vrefint, the power supply voltage value of MCU can be inferred
================================================================================
测试环境：
测试用板：PY32F005_STK
MDK版本： 5.41
IAR版本： 9.20
GCC 版本：GNU Arm Embedded Toolchain 10.3-2021.10

Test environment:
Test board: PY32F005_STK
MDK Version: 5.41
IAR Version: 9.20
GCC Version: GNU Arm Embedded Toolchain 10.3-2021.10
================================================================================
使用步骤：
1. 编译并下载程序；
2. 串口每隔1s打印一次VCC的电压值；

Example execution steps:
1. Compile and download the program;
2. The serial port prints the voltage value of VCC every 1 second;
================================================================================
注意事项：
通过USB转TTL模块连接PC与STK板,STK板与USB转TTL模块的连线方式如下；
STK板          USB转TTL模块
PB4(TX)   -->  RX
GND       -->  GND
UART配置为波特率9600

Notes:
Connect the PC to the STK board through the USB to TTL module, and the connection
method between the STK board and the USB to TTL module is as follows:
STK board     USB to TTL module
PB4(TX)  -->  RX
GND      -->  GND
UART is configured as BaudRate 9600
================================================================================