CC2640R2F怎样才能正确的关闭的uart,从而实现POWER_SAVING

注意下是否初始化了

/*!
* @brief Function to initialize a given UART peripheral
*
* Function to initialize a given UART peripheral specified by the
* particular index value.
*
* @pre UART_init() has been called
*
* @param index Logical peripheral number for the UART indexed into
* the UART_config table
*
* @param params Pointer to a parameter block. If NULL, default
* parameter values will be used. All the fields in
* this structure are RO (read-only).
*
* @return A #UART_Handle upon success. NULL if an error occurs, or if the
* indexed UART peripheral is already opened.
*
* @sa UART_init()
* @sa UART_close()
*/
extern UART_Handle UART_open(uint_least8_t index, UART_Params *params);

可否提供较完整程式码，关于uart open/close的程序，我测试10小时，都会死机
好不容易不死机了，终于底功耗了，但发现uart可能没有open 成功
感恩