stm32f7系列使用printf打印在串口上显示不出来，请各位大佬k...

lxig 提问时间：2020-9-25 19:39 /

问答
是否解决:

#include "stm32f7xx.h"
#include  "stm32f7xx_hal.h"

#include <stdio.h>
#ifdef __GNUC__
/* With GCC/RAISONANCE, small printf (option LD Linker->Libraries->Small printf
set to 'Yes') calls __io_putchar() */
#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else
#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif /* __GNUC__ */

static void Error_Handler(void);
static void CPU_CACHE_Enable(void);
void systemclockinit(int plln,int pllm,int pllp,int pllq);
void uartinit(void);

static UART_HandleTypeDef UARThandle;

int main(void)
{
  /* Enable the CPU Cache */
  CPU_CACHE_Enable();

  HAL_Init();
systemclockinit(432,25,2,9);
uartinit();
printf("hello");
// HAL_icInit();
// printf("my printf test,compile time:%s %s\r\n",__DATE__,__TIME__);
printf("hello");
while(1)
  {
/* if(TIM5CH1_Capture_STA&0X40)

{
temp=TIM5CH1_Capture_STA;
temp*=0xFFFFFFFF;
temp+=TIM5CH1_Capture_VAL;
sprintf(text, "AD value = 0x%04X", temp);

}
*/
  }
}

static void Error_Handler(void)
{
  /* User may add here some code to deal with this error */
  while(1)
  {
  }
}

static void CPU_CACHE_Enable(void)
{
  /* Enable I-Cache */
  SCB_EnableICache();

  /* Enable D-Cache */
  SCB_EnableDCache();
}

//串口初始化
void uartinit(void)
{
UARThandle.Instance=USART1;
UARThandle.Init.BaudRate=115200;
UARThandle.Init.WordLength=UART_WORDLENGTH_8B;
UARThandle.Init.StopBits=UART_STOPBITS_1;
UARThandle.Init.HwFlowCtl=UART_HWCONTROL_NONE;
UARThandle.Init.Parity=UART_PARITY_NONE;
UARThandle.Init.Mode=UART_MODE_TX_RX;
if (HAL_UART_Init(&UARThandle)!=HAL_OK)
{
  Error_Handler();
}
}

//串口回调函数
void HAL_UART_MspInit(UART_HandleTypeDef *huart)
{
  GPIO_InitTypeDef  GPIO_InitStruct;

  RCC_PeriphCLKInitTypeDef RCC_PeriphClkInit;

  /*##-1- Enable peripherals and GPIO Clocks #################################*/
  /* Enable GPIO TX/RX clock */
  __HAL_RCC_GPIOA_CLK_ENABLE();

  /* Select SysClk as source of USART1 clocks */
  RCC_PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART1;
  RCC_PeriphClkInit.Usart1ClockSelection = RCC_USART1CLKSOURCE_SYSCLK;
  HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphClkInit);

  /* Enable USARTx clock */
  __HAL_RCC_USART1_CLK_ENABLE();

  /*##-2- Configure peripheral GPIO ##########################################*/
  /* UART TX GPIO pin configuration  */
  GPIO_InitStruct.Pin    = GPIO_PIN_9;
  GPIO_InitStruct.Mode    = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull    = GPIO_PULLUP;
  GPIO_InitStruct.Speed    = GPIO_SPEED_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF7_USART1;

  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* UART RX GPIO pin configuration  */
  GPIO_InitStruct.Pin = GPIO_PIN_10;
  GPIO_InitStruct.Alternate = GPIO_AF7_USART1;

  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

}

//printf重定向
PUTCHAR_PROTOTYPE
{
  /* Place your implementation of fputc here */
  /* e.g. write a character to the EVAL_COM1 and Loop until the end of transmission */
  HAL_UART_Transmit(&UARThandle, (uint8_t *)&ch, 1, 0xFFFF);

  return ch;
}