代碼現(xiàn)象：從串口發(fā)一個數(shù)據(jù)，串口能夠返回相應的值，

#include "stm32f10x.h"

#include "stm32f10x_gpio.h"

#include "stm32f10x_rcc.h"

#include "stm32f10x_usart.h"

#include "misc.h"

#include "string.h"

#define RX_BUF_SIZE 80

volatile char RX_FLAG_END_LINE = 0;

volatile char RXi;

volatile char RXc;

char RX_BUF[RX_BUF_SIZE] = {'