• MAX6675应用注意事项

    MAX6675应用注意事项

    注意：重定向c库函数printf到huart1，需要加入头文件#include “stdio.h”，同时勾选use MicroLIB选型，堆栈设置稍微大一些。
    在这里插入图片描述

    1. MAX6675采样频率(建议不低于220ms，即0.22s)

    1. 当CS为高电平的时候开始转换，转换时间约为220ms，当CS为低电平时，停止转换，通过SO读取转换结果。否则，读取的数据一直为0或者不变。
    2. 配置SPI时序时，为MODE 0，即SCK空闲电平为0， 采集在上升沿(CPOA=0)，读取数据在下降沿。
    3. SPI通信速率必须小于4.3MHz，通常选取1-2MHz。
      在这里插入图片描述
      在这里插入图片描述
      在这里插入图片描述

    2. 数字滤波

    采集到的温度数据，要采用数字滤波，否则波动会比较大。滤波模式结合自身情况，合理选用。

    3. 多通道MAX6675采集模式

    一个SPI接口，配合N通道片选。
    在这里插入图片描述
    说明：1.片选任意IO管脚即可，低电平有效！
    2.K型热电偶分别接T+，T-；
    3.介于STM32只读，就只用3根线，SO,SCK,CS

    4. 代码

    4.1 max6675.h

    #ifndef _MAX6675_H_ 
#define _MAX6675_H_

#include "main.h"
#include "spi.h"

//#define MAX6675_CS_Pin GPIO_PIN_0
//#define MAX6675_CS_GPIO_Port GPIOB
extern SPI_HandleTypeDef hspi2;

void SPI2_Init(void);
void MAX6675_Init(void);			 //初始化max6675模块 
uint8_t MAX6675_ReadWriteByte(uint8_t txData); //max6675模块读写一个字�?
uint16_t MAX6675_ReadRawValue(void);
float MAX6675_ReadTemperature(void);
void MAX6675_CS(unsigned char choose);
#endif


    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12
    • 13
    • 14
    • 15
    • 16
    • 17
    • 18

    4.2 max6675.c

    #include "max6675.h"

#if 0
SPI_HandleTypeDef hspi2;

/* SPI2 init function */
void SPI2_Init(void)
{
  hspi2.Instance = SPI2;
  hspi2.Init.Mode = SPI_MODE_MASTER;
  hspi2.Init.Direction = SPI_DIRECTION_2LINES;
  hspi2.Init.DataSize = SPI_DATASIZE_8BIT;
  hspi2.Init.CLKPolarity = SPI_POLARITY_LOW;
  hspi2.Init.CLKPhase = SPI_PHASE_1EDGE;
  hspi2.Init.NSS = SPI_NSS_SOFT;
  hspi2.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_256;
  hspi2.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi2.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi2.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi2.Init.CRCPolynomial = 10;
  if (HAL_SPI_Init(&hspi2) != HAL_OK)
  {
    Error_Handler();
  }
}

void HAL_SPI_MspInit(SPI_HandleTypeDef* spiHandle)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(spiHandle->Instance==SPI2)
  {
    __HAL_RCC_SPI2_CLK_ENABLE();
    __HAL_RCC_GPIOB_CLK_ENABLE();
    /**SPI2 GPIO Configuration
    PB13     ------> SPI2_SCK
    PB14     ------> SPI2_MISO
    PB15     ------> SPI2_MOSI
    */
    GPIO_InitStruct.Pin = GPIO_PIN_13|GPIO_PIN_15;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_14;
    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
    GPIO_InitStruct.Pull = GPIO_PULLUP; //GPIO_NOPULL
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
  }
}

void HAL_SPI_MspDeInit(SPI_HandleTypeDef* spiHandle)
{
  if(spiHandle->Instance==SPI2)
  {
    __HAL_RCC_SPI2_CLK_DISABLE();
    /**SPI2 GPIO Configuration
    PB13     ------> SPI2_SCK
    PB14     ------> SPI2_MISO
    PB15     ------> SPI2_MOSI
    */
    HAL_GPIO_DeInit(GPIOB, GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15);
  }
}

#endif

//MAX6675 片选引脚初始化
void GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOB_CLK_ENABLE();

  HAL_GPIO_WritePin(MAX6675_CS_GPIO_Port, MAX6675_CS_Pin, GPIO_PIN_SET);
  /*引脚配置 */
  GPIO_InitStruct.Pin = MAX6675_CS_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_PULLUP;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(MAX6675_CS_GPIO_Port, &GPIO_InitStruct);
}

/**
  * @brief  max66675模块初始化
  * @param  None
  * @retval None
  */
void MAX6675_Init(void)
{
  GPIO_Init();  //片选引脚初始化
//  SPI2_Init();  //spi总线初始化
  MX_SPI2_Init();

  __HAL_SPI_ENABLE(&hspi2);
} 
 
/**
  * @brief  max6675模块读写一个字节的数据
  * @param  txData：要发送的数据
  * @retval 接收到的数据
  */
uint8_t MAX6675_ReadWriteByte(uint8_t txData)
{		
  unsigned char txdata,rxdata;
  txdata = txData;
  HAL_SPI_TransmitReceive(&hspi2,&txdata,&rxdata,1,1000);
  return rxdata;
}  
 
/**
  * @brief  max6675模块读取测得的原始数据
  * @param  None
  * @retval 温度的原始数据
  */
uint16_t MAX6675_ReadRawValue(void)
{
  uint16_t tmp;
  MAX6675_CS(1);
//   HAL_Delay(1);
  MAX6675_CS(0);
//  HAL_Delay(1);
  tmp = MAX6675_ReadWriteByte(0XFF); //read MSB
  tmp <<= 8;
  tmp |= MAX6675_ReadWriteByte(0XFF); //read LSB
  HAL_Delay(1);
  MAX6675_CS(1);
  
  if (tmp & 4) 
  {
    // thermocouple open
    tmp = 4095; //未检测到热电偶
  }
  else 
  {
    tmp = tmp >> 3;
  }
  return tmp;
}
 
/**
  * @brief  max6675模块读取温度
  * @param  None
  * @retval 温度值（单位：℃）
  */
float MAX6675_ReadTemperature(void)
{
  return (MAX6675_ReadRawValue() * 1024.0 / 4096);
}

//MAX6675 片选控制
void MAX6675_CS(unsigned char choose)
{
  if(choose == 1)
  {
    HAL_GPIO_WritePin(GPIOB, MAX6675_CS_Pin, GPIO_PIN_SET);
  }
  else
  {
    HAL_GPIO_WritePin(GPIOB, MAX6675_CS_Pin, GPIO_PIN_RESET);
  }
}


    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12
    • 13
    • 14
    • 15
    • 16
    • 17
    • 18
    • 19
    • 20
    • 21
    • 22
    • 23
    • 24
    • 25
    • 26
    • 27
    • 28
    • 29
    • 30
    • 31
    • 32
    • 33
    • 34
    • 35
    • 36
    • 37
    • 38
    • 39
    • 40
    • 41
    • 42
    • 43
    • 44
    • 45
    • 46
    • 47
    • 48
    • 49
    • 50
    • 51
    • 52
    • 53
    • 54
    • 55
    • 56
    • 57
    • 58
    • 59
    • 60
    • 61
    • 62
    • 63
    • 64
    • 65
    • 66
    • 67
    • 68
    • 69
    • 70
    • 71
    • 72
    • 73
    • 74
    • 75
    • 76
    • 77
    • 78
    • 79
    • 80
    • 81
    • 82
    • 83
    • 84
    • 85
    • 86
    • 87
    • 88
    • 89
    • 90
    • 91
    • 92
    • 93
    • 94
    • 95
    • 96
    • 97
    • 98
    • 99
    • 100
    • 101
    • 102
    • 103
    • 104
    • 105
    • 106
    • 107
    • 108
    • 109
    • 110
    • 111
    • 112
    • 113
    • 114
    • 115
    • 116
    • 117
    • 118
    • 119
    • 120
    • 121
    • 122
    • 123
    • 124
    • 125
    • 126
    • 127
    • 128
    • 129
    • 130
    • 131
    • 132
    • 133
    • 134
    • 135
    • 136
    • 137
    • 138
    • 139
    • 140
    • 141
    • 142
    • 143
    • 144
    • 145
    • 146
    • 147
    • 148
    • 149
    • 150
    • 151
    • 152
    • 153
    • 154
    • 155
    • 156
    • 157
    • 158
    • 159
    • 160
    • 161
    • 162
    • 163

    4.3 spi.h

    /* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    spi.h
  * @brief   This file contains all the function prototypes for
  *          the spi.c file
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Define to prevent recursive inclusion -------------------------------------*/
#ifndef __SPI_H__
#define __SPI_H__

#ifdef __cplusplus
extern "C" {
#endif

/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

extern SPI_HandleTypeDef hspi2;
extern SPI_HandleTypeDef hspi3;

/* USER CODE BEGIN Private defines */

/* USER CODE END Private defines */

void MX_SPI2_Init(void);
void MX_SPI3_Init(void);

/* USER CODE BEGIN Prototypes */

/* USER CODE END Prototypes */

#ifdef __cplusplus
}
#endif

#endif /* __SPI_H__ */


    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12
    • 13
    • 14
    • 15
    • 16
    • 17
    • 18
    • 19
    • 20
    • 21
    • 22
    • 23
    • 24
    • 25
    • 26
    • 27
    • 28
    • 29
    • 30
    • 31
    • 32
    • 33
    • 34
    • 35
    • 36
    • 37
    • 38
    • 39
    • 40
    • 41
    • 42
    • 43
    • 44
    • 45
    • 46
    • 47
    • 48
    • 49
    • 50
    • 51
    • 52
    • 53
    • 54

    4.4 spi.c

    /* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    spi.c
  * @brief   This file provides code for the configuration
  *          of the SPI instances.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "spi.h"

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

SPI_HandleTypeDef hspi2;
SPI_HandleTypeDef hspi3;

/* SPI2 init function */
void MX_SPI2_Init(void)
{

  /* USER CODE BEGIN SPI2_Init 0 */

  /* USER CODE END SPI2_Init 0 */

  /* USER CODE BEGIN SPI2_Init 1 */

  /* USER CODE END SPI2_Init 1 */
  hspi2.Instance = SPI2;
  hspi2.Init.Mode = SPI_MODE_MASTER;
  hspi2.Init.Direction = SPI_DIRECTION_2LINES;
  hspi2.Init.DataSize = SPI_DATASIZE_8BIT;
  hspi2.Init.CLKPolarity = SPI_POLARITY_LOW;
  hspi2.Init.CLKPhase = SPI_PHASE_1EDGE;
  hspi2.Init.NSS = SPI_NSS_SOFT;
  hspi2.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_128;
  hspi2.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi2.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi2.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi2.Init.CRCPolynomial = 10;
  if (HAL_SPI_Init(&hspi2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN SPI2_Init 2 */

  /* USER CODE END SPI2_Init 2 */

}
/* SPI3 init function */
void MX_SPI3_Init(void)
{

  /* USER CODE BEGIN SPI3_Init 0 */

  /* USER CODE END SPI3_Init 0 */

  /* USER CODE BEGIN SPI3_Init 1 */

  /* USER CODE END SPI3_Init 1 */
  hspi3.Instance = SPI3;
  hspi3.Init.Mode = SPI_MODE_MASTER;
  hspi3.Init.Direction = SPI_DIRECTION_2LINES;
  hspi3.Init.DataSize = SPI_DATASIZE_8BIT;
  hspi3.Init.CLKPolarity = SPI_POLARITY_LOW;
  hspi3.Init.CLKPhase = SPI_PHASE_2EDGE;
  hspi3.Init.NSS = SPI_NSS_SOFT;
  hspi3.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_64;
  hspi3.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi3.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi3.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi3.Init.CRCPolynomial = 10;
  if (HAL_SPI_Init(&hspi3) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN SPI3_Init 2 */

  /* USER CODE END SPI3_Init 2 */

}

void HAL_SPI_MspInit(SPI_HandleTypeDef* spiHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(spiHandle->Instance==SPI2)
  {
  /* USER CODE BEGIN SPI2_MspInit 0 */

  /* USER CODE END SPI2_MspInit 0 */
    /* SPI2 clock enable */
    __HAL_RCC_SPI2_CLK_ENABLE();

    __HAL_RCC_GPIOB_CLK_ENABLE();
    /**SPI2 GPIO Configuration
    PB13     ------> SPI2_SCK
    PB14     ------> SPI2_MISO
    PB15     ------> SPI2_MOSI
    */
    GPIO_InitStruct.Pin = GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_PULLUP; //GPIO_NOPULL，这是一个注意的地方，没有外部硬件上拉，改为内部上拉，不改也可以，不稳定
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF5_SPI2;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /* USER CODE BEGIN SPI2_MspInit 1 */

  /* USER CODE END SPI2_MspInit 1 */
  }
  else if(spiHandle->Instance==SPI3)
  {
  /* USER CODE BEGIN SPI3_MspInit 0 */

  /* USER CODE END SPI3_MspInit 0 */
    /* SPI3 clock enable */
    __HAL_RCC_SPI3_CLK_ENABLE();

    __HAL_RCC_GPIOC_CLK_ENABLE();
    /**SPI3 GPIO Configuration
    PC10     ------> SPI3_SCK
    PC11     ------> SPI3_MISO
    PC12     ------> SPI3_MOSI
    */
    GPIO_InitStruct.Pin = GPIO_PIN_10|GPIO_PIN_11|GPIO_PIN_12;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF6_SPI3;
    HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);

  /* USER CODE BEGIN SPI3_MspInit 1 */

  /* USER CODE END SPI3_MspInit 1 */
  }
}

void HAL_SPI_MspDeInit(SPI_HandleTypeDef* spiHandle)
{

  if(spiHandle->Instance==SPI2)
  {
  /* USER CODE BEGIN SPI2_MspDeInit 0 */

  /* USER CODE END SPI2_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_SPI2_CLK_DISABLE();

    /**SPI2 GPIO Configuration
    PB13     ------> SPI2_SCK
    PB14     ------> SPI2_MISO
    PB15     ------> SPI2_MOSI
    */
    HAL_GPIO_DeInit(GPIOB, GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15);

  /* USER CODE BEGIN SPI2_MspDeInit 1 */

  /* USER CODE END SPI2_MspDeInit 1 */
  }
  else if(spiHandle->Instance==SPI3)
  {
  /* USER CODE BEGIN SPI3_MspDeInit 0 */

  /* USER CODE END SPI3_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_SPI3_CLK_DISABLE();

    /**SPI3 GPIO Configuration
    PC10     ------> SPI3_SCK
    PC11     ------> SPI3_MISO
    PC12     ------> SPI3_MOSI
    */
    HAL_GPIO_DeInit(GPIOC, GPIO_PIN_10|GPIO_PIN_11|GPIO_PIN_12);

  /* USER CODE BEGIN SPI3_MspDeInit 1 */

  /* USER CODE END SPI3_MspDeInit 1 */
  }
}

/* USER CODE BEGIN 1 */

/* USER CODE END 1 */


    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12
    • 13
    • 14
    • 15
    • 16
    • 17
    • 18
    • 19
    • 20
    • 21
    • 22
    • 23
    • 24
    • 25
    • 26
    • 27
    • 28
    • 29
    • 30
    • 31
    • 32
    • 33
    • 34
    • 35
    • 36
    • 37
    • 38
    • 39
    • 40
    • 41
    • 42
    • 43
    • 44
    • 45
    • 46
    • 47
    • 48
    • 49
    • 50
    • 51
    • 52
    • 53
    • 54
    • 55
    • 56
    • 57
    • 58
    • 59
    • 60
    • 61
    • 62
    • 63
    • 64
    • 65
    • 66
    • 67
    • 68
    • 69
    • 70
    • 71
    • 72
    • 73
    • 74
    • 75
    • 76
    • 77
    • 78
    • 79
    • 80
    • 81
    • 82
    • 83
    • 84
    • 85
    • 86
    • 87
    • 88
    • 89
    • 90
    • 91
    • 92
    • 93
    • 94
    • 95
    • 96
    • 97
    • 98
    • 99
    • 100
    • 101
    • 102
    • 103
    • 104
    • 105
    • 106
    • 107
    • 108
    • 109
    • 110
    • 111
    • 112
    • 113
    • 114
    • 115
    • 116
    • 117
    • 118
    • 119
    • 120
    • 121
    • 122
    • 123
    • 124
    • 125
    • 126
    • 127
    • 128
    • 129
    • 130
    • 131
    • 132
    • 133
    • 134
    • 135
    • 136
    • 137
    • 138
    • 139
    • 140
    • 141
    • 142
    • 143
    • 144
    • 145
    • 146
    • 147
    • 148
    • 149
    • 150
    • 151
    • 152
    • 153
    • 154
    • 155
    • 156
    • 157
    • 158
    • 159
    • 160
    • 161
    • 162
    • 163
    • 164
    • 165
    • 166
    • 167
    • 168
    • 169
    • 170
    • 171
    • 172
    • 173
    • 174
    • 175
    • 176
    • 177
    • 178
    • 179
    • 180
    • 181
    • 182
    • 183
    • 184
    • 185
    • 186
    • 187
    • 188
    • 189
    • 190
    • 191
    • 192
    • 193
    • 194
    • 195
    • 196
    • 197

    4.5 main.h

    /* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.h
  * @brief          : Header for main.c file.
  *                   This file contains the common defines of the application.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */

/* Define to prevent recursive inclusion -------------------------------------*/
#ifndef __MAIN_H
#define __MAIN_H

#ifdef __cplusplus
extern "C" {
#endif

/* Includes ------------------------------------------------------------------*/
#include "stm32f4xx_hal.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Exported types ------------------------------------------------------------*/
/* USER CODE BEGIN ET */

/* USER CODE END ET */

/* Exported constants --------------------------------------------------------*/
/* USER CODE BEGIN EC */

/* USER CODE END EC */

/* Exported macro ------------------------------------------------------------*/
/* USER CODE BEGIN EM */

/* USER CODE END EM */

/* Exported functions prototypes ---------------------------------------------*/
void Error_Handler(void);

/* USER CODE BEGIN EFP */

/* USER CODE END EFP */

/* Private defines -----------------------------------------------------------*/
#define LED0_Pin GPIO_PIN_9
#define LED0_GPIO_Port GPIOF
#define LED1_Pin GPIO_PIN_10
#define LED1_GPIO_Port GPIOF
#define MAX6675_CS_Pin GPIO_PIN_0
#define MAX6675_CS_GPIO_Port GPIOB
/* USER CODE BEGIN Private defines */

/* USER CODE END Private defines */

#ifdef __cplusplus
}
#endif

#endif /* __MAIN_H */


    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12
    • 13
    • 14
    • 15
    • 16
    • 17
    • 18
    • 19
    • 20
    • 21
    • 22
    • 23
    • 24
    • 25
    • 26
    • 27
    • 28
    • 29
    • 30
    • 31
    • 32
    • 33
    • 34
    • 35
    • 36
    • 37
    • 38
    • 39
    • 40
    • 41
    • 42
    • 43
    • 44
    • 45
    • 46
    • 47
    • 48
    • 49
    • 50
    • 51
    • 52
    • 53
    • 54
    • 55
    • 56
    • 57
    • 58
    • 59
    • 60
    • 61
    • 62
    • 63
    • 64
    • 65
    • 66
    • 67
    • 68
    • 69
    • 70
    • 71
    • 72
    • 73
    • 74
    • 75

    4.6 main.c

    /* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "spi.h"
#include "usart.h"
#include "gpio.h"
#include "stdio.h"
#include "./max6675/max6675.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */
uint16_t max6675_regValue = 0x0000;
float max6675_temperature = 0.0;
/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_SPI2_Init();
  MX_SPI3_Init();
  MX_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
	MAX6675_Init();
	
	printf("max6675\n");
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */
	max6675_regValue = MAX6675_ReadRawValue();
	max6675_temperature = (float)max6675_regValue*1024.0/4096.0;
	printf("max6675_regValue:%x, temperature:%.1f\n", max6675_regValue, max6675_temperature);
  HAL_Delay(1000);
    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}


/**
  * 函数功能: 重定向c库函数printf到huart1
  * 输入参数: 无
  * 返 回 值: 无
  * 说    明：无
  */
int fputc(int ch, FILE *f)
{
  HAL_UART_Transmit(&huart1, (uint8_t *)&ch, 1, 0xffff);
  return ch;
}


/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Configure the main internal regulator output voltage
  */
  __HAL_RCC_PWR_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 4;
  RCC_OscInitStruct.PLL.PLLN = 168;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = 4;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }
  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
  {
    Error_Handler();
  }
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */



    • 1
    • 2
    • 3
    • 4
    • 5
    • 6
    • 7
    • 8
    • 9
    • 10
    • 11
    • 12
    • 13
    • 14
    • 15
    • 16
    • 17
    • 18
    • 19
    • 20
    • 21
    • 22
    • 23
    • 24
    • 25
    • 26
    • 27
    • 28
    • 29
    • 30
    • 31
    • 32
    • 33
    • 34
    • 35
    • 36
    • 37
    • 38
    • 39
    • 40
    • 41
    • 42
    • 43
    • 44
    • 45
    • 46
    • 47
    • 48
    • 49
    • 50
    • 51
    • 52
    • 53
    • 54
    • 55
    • 56
    • 57
    • 58
    • 59
    • 60
    • 61
    • 62
    • 63
    • 64
    • 65
    • 66
    • 67
    • 68
    • 69
    • 70
    • 71
    • 72
    • 73
    • 74
    • 75
    • 76
    • 77
    • 78
    • 79
    • 80
    • 81
    • 82
    • 83
    • 84
    • 85
    • 86
    • 87
    • 88
    • 89
    • 90
    • 91
    • 92
    • 93
    • 94
    • 95
    • 96
    • 97
    • 98
    • 99
    • 100
    • 101
    • 102
    • 103
    • 104
    • 105
    • 106
    • 107
    • 108
    • 109
    • 110
    • 111
    • 112
    • 113
    • 114
    • 115
    • 116
    • 117
    • 118
    • 119
    • 120
    • 121
    • 122
    • 123
    • 124
    • 125
    • 126
    • 127
    • 128
    • 129
    • 130
    • 131
    • 132
    • 133
    • 134
    • 135
    • 136
    • 137
    • 138
    • 139
    • 140
    • 141
    • 142
    • 143
    • 144
    • 145
    • 146
    • 147
    • 148
    • 149
    • 150
    • 151
    • 152
    • 153
    • 154
    • 155
    • 156
    • 157
    • 158
    • 159
    • 160
    • 161
    • 162
    • 163
    • 164
    • 165
    • 166
    • 167
    • 168
    • 169
    • 170
    • 171
    • 172
    • 173
    • 174
    • 175
    • 176
    • 177
    • 178
    • 179
    • 180
    • 181
    • 182
    • 183
    • 184
    • 185
    • 186
    • 187
    • 188
    • 189
    • 190
    • 191
    • 192
    • 193
    • 194
    • 195
    • 196
    • 197
    • 198
    • 199
    • 200
    • 201
    • 202
    • 203
    • 204
    • 205
    • 206
    • 207
    • 208

    注意：重定向c库函数printf到huart1，需要加入头文件#include “stdio.h”，同时勾选use MicroLIB选型，堆栈设置稍微大一些。

    5. 测试结果（要想波动小，加上数字滤波）

    在这里插入图片描述
    在这里插入图片描述
    在这里插入图片描述

  • 相关阅读:
    vue3怎么创建项目
    【JavaWeb】
    Spring Security 核心解读（一）整体架构
    公司应该如何招人？
    【音视频-FFMPEG相关命令使用】
    vue3: 2.如何利用 effectScope 自己实现一个青铜版pinia 一 getters篇
    日常工作中需要避免的9个React坏习惯
    【代码学习】pytorch_lightning
    2023年新授的IBDP物理/化学/生物课程有何不同？
    get_shape_model_contours
  • 原文地址：https://blog.csdn.net/m0_46577050/article/details/127682022