利用两块stm32开发板进行串口通信。A板发送hello siri，B板在收到以后返回I AM NOT SIRI。要求A板的LCD上显示发送和接收到的数据。B板不需要显示屏。AB板自由选择合适的串口。

可以使用STM32的UART模块来实现串口通信。首先，需要在A板和B板上分别配置UART模块，并设置波特率、数据位、停止位和校验位等参数。然后，A板通过UART发送"hello siri"字符串，B板接收到后返回"I AM NOT SIRI"字符串。在A板上，可以通过LCD显示发送和接收到的数据，可以使用串口中断来实现接收数据的处理。在B板上，可以直接通过串口发送数据，不需要显示屏。

以下是A板的代码示例：

#include "stm32f10x.h"
#include "stdio.h"
#include "string.h"

#define USART1_TX_PIN GPIO_Pin_9
#define USART1_RX_PIN GPIO_Pin_10

void USART1_Config(void);
void LCD_Display(char *str);

int main(void)
{
    USART1_Config();
    LCD_Display("Sending: hello siri\n");

    while (1)
    {
        USART_SendData(USART1, 'h');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 'e');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 'l');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 'l');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 'o');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, ' ');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 's');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 'i');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 'r');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, 'i');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        USART_SendData(USART1, '\n');
        while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        delay_ms(1000);
    }
}

void USART1_Config(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

    GPIO_InitStructure.GPIO_Pin = USART1_TX_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = USART1_RX_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    USART_InitStructure.USART_BaudRate = 9600;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_Parity = USART_Parity_No;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
    USART_Init(USART1, &USART_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);

    USART_Cmd(USART1, ENABLE);
}

void USART1_IRQHandler(void)
{
    if (USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)
    {
        char ch = USART_ReceiveData(USART1);
        char str[20];
        sprintf(str, "Received: %c\n", ch);
        LCD_Display(str);
        if (ch == 'o')
        {
            USART_SendData(USART1, 'I');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, ' ');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'A');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'M');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, ' ');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'N');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'O');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'T');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, ' ');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'S');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'I');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'R');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, 'I');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
            USART_SendData(USART1, '\n');
            while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
        }
    }
}

void LCD_Display(char *str)
{
    // TODO: LCD显示函数的实现
}

void delay_ms(uint32_t ms)
{
    uint32_t i, j;
    for (i = 0; i < ms; i++)
    {
        for (j = 0; j < 7200; j++);
    }
}

以下是B板的代码示例：

#include "stm32f10x.h"
#include "stdio.h"
#include "string.h"

#define USART2_TX_PIN GPIO_Pin_2
#define USART2_RX_PIN GPIO_Pin_3

void USART2_Config(void);

int main(void)
{
    USART2_Config();

    while (1)
    {
    }
}

void USART2_Config(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);

    GPIO_InitStructure.GPIO_Pin = USART2_TX_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = USART2_RX_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    USART_InitStructure.USART_BaudRate = 9600;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_Parity = USART_Parity_No;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
    USART_Init(USART2, &USART_InitStructure);

    USART_Cmd(USART2, ENABLE);
}

void USART2_IRQHandler(void)
{
    // TODO: USART2中断处理函数的实现
}