基于STM32F407 MCU，写一段通过串口和Ymodem协议接收bin文件进行在线升级的代码，使用C语言

以下是一个基于STM32F407 MCU的串口Ymodem协议在线升级代码示例：

#include "stm32f4xx.h"
#include <string.h>

#define FLASH_START_ADDRESS 0x08000000
#define FLASH_END_ADDRESS   0x08080000  // 512KB Flash

#define UART_TIMEOUT_MS     1000        // UART接收超时时间，单位毫秒
#define FLASH_PAGE_SIZE     2048        // Flash页大小
#define BUFFER_SIZE         2048        // 缓存区大小

#define SOH                 0x01        // Ymodem协议Start of Header标志
#define STX                 0x02        // Ymodem协议Start of Text标志
#define EOT                 0x04        // Ymodem协议End of Transmission标志
#define ACK                 0x06        // Ymodem协议Acknowledge标志
#define NAK                 0x15        // Ymodem协议Negative Acknowledge标志
#define CAN                 0x18        // Ymodem协议Cancel标志
#define CRC16               0x43        // Ymodem协议CRC16标志

uint8_t buffer[BUFFER_SIZE];            // 缓存区
uint8_t filename[128];                  // 文件名
uint32_t filesize;                      // 文件大小

void erase_flash(uint32_t start_addr, uint32_t end_addr)
{
    FLASH_EraseInitTypeDef erase_init;
    uint32_t page_error;

    HAL_FLASH_Unlock();

    erase_init.TypeErase = FLASH_TYPEERASE_SECTORS;
    erase_init.Sector = FLASH_SECTOR_0;
    erase_init.NbSectors = (end_addr - start_addr) / FLASH_PAGE_SIZE;
    erase_init.VoltageRange = FLASH_VOLTAGE_RANGE_3;

    HAL_FLASHEx_Erase(&erase_init, &page_error);

    HAL_FLASH_Lock();
}

void write_flash(uint32_t addr, uint8_t *data, uint32_t size)
{
    uint32_t i;
    uint32_t remainder = addr % FLASH_PAGE_SIZE;
    uint32_t start_address = addr - remainder;
    uint32_t page_count = (size + remainder + FLASH_PAGE_SIZE - 1) / FLASH_PAGE_SIZE;

    if (HAL_FLASH_Unlock() != HAL_OK) {
        return;
    }

    for (i = 0; i < page_count; i++) {
        uint32_t page_address = start_address + i * FLASH_PAGE_SIZE;
        uint32_t offset = i == 0 ? remainder : 0;
        uint32_t write_size = i == page_count - 1 ? (size - i * FLASH_PAGE_SIZE + remainder) : FLASH_PAGE_SIZE;

        uint32_t j;
        for (j = 0; j < write_size; j++) {
            buffer[j + offset] = data[i * FLASH_PAGE_SIZE + j];
        }

        HAL_FLASH_Program(FLASH_TYPEPROGRAM_FLASHWORD, page_address, (uint64_t*)buffer);

        uint32_t k;
        for (k = 0; k < write_size; k += 4) {
            if (*(uint32_t*)(page_address + k) != *(uint32_t*)(buffer + k)) {
                return;
            }
        }
    }

    HAL_FLASH_Lock();
}

uint32_t get_crc16(uint8_t *data, uint32_t size)
{
    uint32_t i, j;
    uint32_t crc = 0;
    for (i = 0; i < size; i++) {
        crc ^= ((uint32_t)data[i] << 8);
        for (j = 0; j < 8; j++) {
            if ((crc & 0x8000) != 0) {
                crc = (crc << 1) ^ 0x1021;
            } else {
                crc = (crc << 1);
            }
        }
    }
    return crc;
}

int receive_ymodem(int fd)
{
    uint8_t packet_number = 0;
    uint32_t bytes_received = 0;
    uint32_t crc = 0;
    uint32_t expected_crc = 0;
    uint16_t block_size = 128;
    uint8_t packet[1024];
    uint8_t packet_type;

    erase_flash(FLASH_START_ADDRESS, FLASH_END_ADDRESS);

    while (1) {
        HAL_StatusTypeDef status;
        uint32_t start_time = HAL_GetTick();
        do {
            status = HAL_UART_Receive(fd, packet, 1, UART_TIMEOUT_MS);
            if (status == HAL_OK) {
                break;
            }
        } while (HAL_GetTick() - start_time < UART_TIMEOUT_MS);

        if (status != HAL_OK) {
            HAL_UART_Transmit(fd, &NAK, 1, UART_TIMEOUT_MS);
            continue;
        }

        switch (packet[0]) {
        case SOH:
            block_size = 128;
            packet_type = SOH;
            break;
        case STX:
            block_size = 1024;
            packet_type = STX;
            break;
        case EOT:
            HAL_UART_Transmit(fd, &ACK, 1, UART_TIMEOUT_MS);
            return 1;
        case CAN:
            if (HAL_UART_Receive(fd, packet, 1, UART_TIMEOUT_MS) == HAL_OK && packet[0] == CAN) {
                HAL_UART_Transmit(fd, &ACK, 1, UART_TIMEOUT_MS);
                return 0;
            }
            break;
        default:
            break;
        }

        if (packet_type == SOH || packet_type == STX) {
            uint8_t packet[1024];
            uint8_t packet_number_complement;
            uint16_t i;

            packet_number++;
            packet_number_complement = ~packet_number;

            if (HAL_UART_Receive(fd, packet, block_size + 4, UART_TIMEOUT_MS) != HAL_OK) {
                HAL_UART_Transmit(fd, &NAK, 1, UART_TIMEOUT_MS);
                continue;
            }

            if (packet[0] != packet_number || packet[1] != packet_number_complement) {
                HAL_UART_Transmit(fd, &NAK, 1, UART_TIMEOUT_MS);
                continue;
            }

            crc = get_crc16(packet + 2, block_size);
            expected_crc = (packet[block_size + 2] << 8) | packet[block_size + 3];

            if (crc != expected_crc) {
                HAL_UART_Transmit(fd, &NAK, 1, UART_TIMEOUT_MS);
                continue;
            }

            for (i = 0; i < block_size; i++) {
                buffer[bytes_received + i] = packet[i + 2];
            }

            bytes_received += block_size;

            HAL_UART_Transmit(fd, &ACK, 1, UART_TIMEOUT_MS);
        }
    }
}

int main(void)
{
    /* 初始化串口 */

    /* 初始化 Ymodem 协议 */
    
    /* 等待接收文件 */

    /* 升级完成后，跳转到新固件 */
    void (*new_app)(void) = (void*)FLASH_START_ADDRESS;
    new_app();

    while (1);
}

注意，以上代码仅是示例，实际使用时需要根据具体的硬件和软件环境进行适当修改和调试。