You are required to write a C program to: • Initialize GPIO peripherals • Initialise UART peripheral for receiving ASCII characters ‘A’ to ‘Z’ at baud 9600 • Initialise an internal array to hold 10 characters with head and tail: CharBuff • Repeat the following:o When data is received on the serial communication port, read ASCII character X, o If received character X is a capital letter add it to CharBuff, else ignore. o While CharBuff is not empty, transmit the morse code of the oldest stored character by blinking the LED (code provided for you). o When CharBuff is full, disable UART RX. o If UART RX is disabled, pushing the button P_B1 will activate it; otherwise, pushing the button does not affect your programme. You are recommended to use interrupt to control UART receiving data and coordinate the operation between CharBuff and P_LD2. 在我的代码基础上完成以上任务#include <platform.h> #include <gpio.h> #include "delay.h" #include "uart.h" #include <stm32f4xx.h> /* NOTE******** YOU CAN USE THE IN-UILT FUNCTION delay_ms(HOW_LONG) TO CAUSE A DELAY OF HOW_LONG MILLI SECONDS

由于您的要求涉及到硬件操作和中断控制，需要在具体的嵌入式系统上进行编程。下面是一个基于 STM32F4xx 的 C 代码示例，可以实现您所要求的功能：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "stm32f4xx.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_usart.h"

#define BUFFER_SIZE 10

GPIO_InitTypeDef GPIO_InitStruct;
USART_InitTypeDef USART_InitStruct;
NVIC_InitTypeDef NVIC_InitStruct;

volatile char CharBuff[BUFFER_SIZE];
volatile int head = 0;
volatile int tail = 0;
volatile int buffer_full = 0;
volatile int uart_rx_enabled = 1;

void init_gpio(void) {
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_5;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_DOWN;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_2;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_USART2);
}

void init_uart(void) {
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);

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

    NVIC_InitStruct.NVIC_IRQChannel = USART2_IRQn;
    NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStruct.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStruct);

    USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);

    USART_Cmd(USART2, ENABLE);
}

void USART2_IRQHandler(void) {
    if (USART_GetITStatus(USART2, USART_IT_RXNE) != RESET) {
        char data = USART_ReceiveData(USART2);

        if (data >= 'A' && data <= 'Z' && !buffer_full && uart_rx_enabled) {
            CharBuff[tail] = data;
            tail = (tail + 1) % BUFFER_SIZE;

            if (tail == head) {
                buffer_full = 1;
                USART_ITConfig(USART2, USART_IT_RXNE, DISABLE);
            }
        }

        USART_ClearITPendingBit(USART2, USART_IT_RXNE);
    }
}

void blink_led(char data) {
    int i, j;
    int dot_time = 200;
    int dash_time = 500;

    switch (data) {
        case 'A':
            GPIO_SetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dot_time);
            GPIO_ResetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dash_time);
            GPIO_SetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dot_time);
            GPIO_ResetBits(GPIOA, GPIO_Pin_5);
            break;
        case 'B':
            GPIO_SetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dash_time);
            GPIO_ResetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dot_time);
            GPIO_SetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dot_time);
            GPIO_ResetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dot_time);
            GPIO_SetBits(GPIOA, GPIO_Pin_5);
            delay_ms(dot_time);
            GPIO_ResetBits(GPIOA, GPIO_Pin_5);
            break;
        // Add more cases for the rest of the alphabet...
    }
}

int main(void) {
    init_gpio();
    init_uart();

    while (1) {
        if (head != tail) {
            blink_led(CharBuff[head]);
            head = (head + 1) % BUFFER_SIZE;

            if (buffer_full) {
                buffer_full = 0;
                USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
            }
        }

        if (!UART_RX_ENABLED && GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_0)) {
            UART_RX_ENABLED = 1;
            USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
        }
    }
}

该程序使用 STM32F4xx 的 GPIO 和 USART 模块来实现所需的功能。其中，`init_gpio()` 函数用于初始化 GPIO 端口，`init_uart()` 函数用于初始化 USART 端口。在中断服务函数 `USART2_IRQHandler()` 中，程序会检测是否有数据通过 USART 接收到，如果是大写字母且 CharBuff 没有满，那么将其添加到 CharBuff 中。如果 CharBuff 已满，则禁用 UART RX 中断。在主循环中，程序会周期性地检查 CharBuff 是否有数据，如果有则将其转换为 Morse 代码并通过 LED 闪烁输出。当 CharBuff 已满时，程序会禁用 UART RX 中断，直到 CharBuff 又有空间可用。同时，程序会检测 P_B1 按键是否按下，如果按下且 UART RX 已禁用，则启用 UART RX 中断。