20 IAP程序下载到80%就下不进去了

发布于 2020-09-13 15:05:10 浏览：1103 订阅该版

![IAP.png](/uploads/20200913/cda6cea0c4aa8adf208bbd3a0ae9421a.png)
芯片我用的是STM32L412,IAP程序参考了L4固件库的IAP例程，
```c
COM_StatusTypeDef Ymodem_Receive ( uint32_t *p_size )
{
  uint32_t i, packet_length, session_done = 0, file_done, errors = 0, session_begin = 0;
  uint32_t flashdestination, ramsource, filesize;
  uint8_t *file_ptr;
  uint8_t file_size[FILE_SIZE_LENGTH], tmp, packets_received;
  COM_StatusTypeDef result = COM_OK;

/* Initialize flashdestination variable */
  flashdestination = APPLICATION_ADDRESS;

while ((session_done == 0) && (result == COM_OK))
  {
    packets_received = 0;
    file_done = 0;
    while ((file_done == 0) && (result == COM_OK))
    {
      switch (ReceivePacket(aPacketData, &packet_length, DOWNLOAD_TIMEOUT))
      {
        case HAL_OK:
          errors = 0;
          switch (packet_length)
          {
            case 2:
              /* Abort by sender */
              Serial_PutByte(ACK);
              result = COM_ABORT;
              break;
            case 0:
              /* End of transmission */
              Serial_PutByte(ACK);
              file_done = 1;
              break;
            default:
              /* Normal packet */
              if (aPacketData[PACKET_NUMBER_INDEX] != packets_received)
              {
                Serial_PutByte(NAK);
              }
              else
              {
                if (packets_received == 0)
                {
                  /* File name packet */
                  if (aPacketData[PACKET_DATA_INDEX] != 0)
                  {
                    /* File name extraction */
                    i = 0;
                    file_ptr = aPacketData + PACKET_DATA_INDEX;
                    while ( (*file_ptr != 0) && (i < FILE_NAME_LENGTH))
                    {
                      aFileName[i++] = *file_ptr++;
                    }

/* File size extraction */
                    aFileName[i++] = '\0';
                    i = 0;
                    file_ptr ++;
                    while ( (*file_ptr != ' ') && (i < FILE_SIZE_LENGTH))
                    {
                      file_size[i++] = *file_ptr++;
                    }
                    file_size[i++] = '\0';
                    Str2Int(file_size, &filesize);

/* Test the size of the image to be sent */
                    /* Image size is greater than Flash size */
                    if (*p_size > (USER_FLASH_SIZE + 1))
                    {
                      /* End session */
                      tmp = CA;
                      HAL_UART_Transmit(&UartHandle, &tmp, 1, NAK_TIMEOUT);
                      HAL_UART_Transmit(&UartHandle, &tmp, 1, NAK_TIMEOUT);
                      result = COM_LIMIT;
                    }
                    /* erase user application area */
                    FLASH_If_Erase(APPLICATION_ADDRESS);
                    *p_size = filesize;

Serial_PutByte(ACK);
                    Serial_PutByte(CRC16);
                  }
                  /* File header packet is empty, end session */
                  else
                  {
                    Serial_PutByte(ACK);
                    file_done = 1;
                    session_done = 1;
                    break;
                  }
                }
                else /* Data packet */
                {
                  ramsource = (uint32_t) & aPacketData[PACKET_DATA_INDEX];

/* Write received data in Flash */
                  if (FLASH_If_Write(flashdestination, (uint32_t*) ramsource, packet_length/4) == FLASHIF_OK)                   
                  {
                    flashdestination += packet_length;
                    Serial_PutByte(ACK);
                  }
                  else /* An error occurred while writing to Flash memory */
                  {
                    /* End session */
                    Serial_PutByte(CA);
                    Serial_PutByte(CA);
                    result = COM_DATA;
                  }
                }
                packets_received ++;
                session_begin = 1;
              }
              break;
          }
          break;
        case HAL_BUSY: /* Abort actually */
          Serial_PutByte(CA);
          Serial_PutByte(CA);
          result = COM_ABORT;
          break;
        default:
          if (session_begin > 0)
          {
            errors ++;
          }
          if (errors > MAX_ERRORS)
          {
            /* Abort communication */
            Serial_PutByte(CA);
            Serial_PutByte(CA);
          }
          else
          {
            Serial_PutByte(CRC16); /* Ask for a packet */
          }
          break;
      }
    }
  }
  return result;
}
```
传到80%的时候ReceivePacket的返回值就是错误码了
有遇到过类似问题的朋友么？