traffic_light_example.c            --灯光和蜂鸣器控制源文件

IoTWatchDogDisable： 关闭看门狗函数

IoTGpioInit(unsigned int id)： 初始化GPIO
	参数说明：
	–id Indicates the GPIO pin number.
	
IoTIoSetFunc(IOT_GPIO_IO_NAME id, unsigned char val)：	注册功能
	参数说明：
	-id Indicates the GPIO pin number.
	-val 复用功能
	
IoTGpioSetDir(unsigned int id, IotGpioDir dir)：Sets the direction for a GPIO pin.
	参数说明：
	-id Indicates the GPIO pin number.
	-dir IO方向
	
IotIoSetPull(IOT_GPIO_IO_NAME id, IOT_IO_PULL val)：设置GPIO为上拉或下拉
	参数说明：
	-id Indicates the GPIO pin number.
	-val 上拉或下拉	
	
IoTGpioRegisterIsrFunc(unsigned int id, IotGpioIntType intType, IotGpioIntPolarity intPolarity, GpioIsrCallbackFunc func, char *arg)：	Enables the interrupt feature for a GPIO pin.
	参数说明：
	-id Indicates the GPIO pin number.
	-intType Indicates the interrupt type.
	-intPolarity Indicates the interrupt polarity.
	-func Indicates the interrupt callback function.
	-arg Indicates the pointer to the argument used in the interrupt callback function.
	
IoTGpioSetOutputVal(unsigned int id, IotGpioValue val)：Sets the output level value for a GPIO pin.
	参数说明：
	-id	Indicates the GPIO pin number.
	-val Indicates the output level value.
	
IoTPwmInit(unsigned int port)： Initializes a PWM device.
	参数说明：
	-port Indicates the port number of the PWM device
	
osThreadNew(osThreadFunc_t func, void *argument, const osThreadAttr_t *attr)：Creates an active thread. 
	参数说明：
	-func Indicates the entry of the thread callback function.
	-argument Indicates the pointer to the argument passed to the thread.
	-attr Indicates the thread attributes.	
	
IoTPwmStart(unsigned int port, unsigned short duty, unsigned int freq)：Starts PWM signal output from a specified port based on the given output frequency and duty cycle.
	参数说明：
	-port Indicates the port number of the PWM device.
	-duty Indicates the duty cycle for PWM signal output. The value ranges from 1 to 99.
	-freq Indicates the frequency for PWM signal output.
	
IoTPwmStop(unsigned int port)：Stops PWM signal output from a specified port.
	参数说明：
	-port Indicates the port number of the PWM device.		

先每个灯闪烁一下，亮2秒灭1秒，2遍，测试4个灯是否正常。
按键每按下一次，切换一次灯亮同时改变蜂鸣器状态，蜂鸣器状态为1时，蜂鸣。