【STM32G431RBTx】备战蓝桥杯嵌入式→基本模块→I2C→M24C02

文章目录

前言
I2C
- 1.原理图以及配置元素
- 2.CubeMx的配置步骤
- 3.生成工程
- 4.测试代码
- 5.演示效果
总结

前言

G4板载了一块M24C02(eeprom)和一块MCP4017(可编程电阻)，省赛中多考M24C02，本篇文章讲述如何用软件I2驱动M24C02。

I2C

1.原理图以及配置元素

分析:由图可知，PB6为I2C的SCL线，PB7为I2C的SDA线

2.CubeMx的配置步骤

大赛是提供了I2C的驱动的这里我们只需要把两个引脚设置输出模式就行了，不再需要其他步骤。

3.生成工程

将红框中的两个文件复制黏贴到工程文件夹中的bsp文件夹中并改名为i2c.c和i2c.h。

在bsp文件中新建i2cc.c和i2c.h文件
打开工程将两个文件添加到工程中去

至此工程就建立完毕了

4.测试代码

i2c.h:

#ifndef __I2C_H
#define __I2C_H#include "main.h"void I2CStart(void);
void I2CStop(void);
unsigned char I2CWaitAck(void);
void I2CSendAck(void);
void I2CSendNotAck(void);
void I2CSendByte(unsigned char cSendByte);
unsigned char I2CReceiveByte(void);
void I2CInit(void);/*******下方为自己添加的函数声明**************/
unsigned char eeprom_read(unsigned char addr);
void eeprom_write(unsigned char addr, unsigned char dat);#endif

i2c.c:

#include "i2c.h"#define DELAY_TIME   20/*** @brief SDA线输入模式配置* @param None* @retval None*/
void SDA_Input_Mode()
{GPIO_InitTypeDef GPIO_InitStructure = {0};GPIO_InitStructure.Pin = GPIO_PIN_7;GPIO_InitStructure.Mode = GPIO_MODE_INPUT;GPIO_InitStructure.Pull = GPIO_PULLUP;GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_HIGH;HAL_GPIO_Init(GPIOB, &GPIO_InitStructure);
}/*** @brief SDA线输出模式配置* @param None* @retval None*/
void SDA_Output_Mode()
{GPIO_InitTypeDef GPIO_InitStructure = {0};GPIO_InitStructure.Pin = GPIO_PIN_7;GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_OD;GPIO_InitStructure.Pull = GPIO_NOPULL;GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_HIGH;HAL_GPIO_Init(GPIOB, &GPIO_InitStructure);
}/*** @brief SDA线输出一个位* @param val 输出的数据* @retval None*/
void SDA_Output( uint16_t val )
{if ( val ){GPIOB->BSRR |= GPIO_PIN_7;}else{GPIOB->BRR |= GPIO_PIN_7;}
}/*** @brief SCL线输出一个位* @param val 输出的数据* @retval None*/
void SCL_Output( uint16_t val )
{if ( val ){GPIOB->BSRR |= GPIO_PIN_6;}else{GPIOB->BRR |= GPIO_PIN_6;}
}/*** @brief SDA输入一位* @param None* @retval GPIO读入一位*/
uint8_t SDA_Input(void)
{if(HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_7) == GPIO_PIN_SET){return 1;}else{return 0;}
}/*** @brief I2C的短暂延时* @param None* @retval None*/
static void delay1(unsigned int n)
{uint32_t i;for ( i = 0; i < n; ++i);
}/*** @brief I2C起始信号* @param None* @retval None*/
void I2CStart(void)
{SDA_Output(1);delay1(DELAY_TIME);SCL_Output(1);delay1(DELAY_TIME);SDA_Output(0);delay1(DELAY_TIME);SCL_Output(0);delay1(DELAY_TIME);
}/*** @brief I2C结束信号* @param None* @retval None*/
void I2CStop(void)
{SCL_Output(0);delay1(DELAY_TIME);SDA_Output(0);delay1(DELAY_TIME);SCL_Output(1);delay1(DELAY_TIME);SDA_Output(1);delay1(DELAY_TIME);}/*** @brief I2C等待确认信号* @param None* @retval None*/
unsigned char I2CWaitAck(void)
{unsigned short cErrTime = 5;SDA_Input_Mode();delay1(DELAY_TIME);SCL_Output(1);delay1(DELAY_TIME);while(SDA_Input()){cErrTime--;delay1(DELAY_TIME);if (0 == cErrTime){SDA_Output_Mode();I2CStop();return ERROR;}}SDA_Output_Mode();SCL_Output(0);delay1(DELAY_TIME);return SUCCESS;
}/*** @brief I2C发送确认信号* @param None* @retval None*/
void I2CSendAck(void)
{SDA_Output(0);delay1(DELAY_TIME);delay1(DELAY_TIME);SCL_Output(1);delay1(DELAY_TIME);SCL_Output(0);delay1(DELAY_TIME);}/*** @brief I2C发送非确认信号* @param None* @retval None*/
void I2CSendNotAck(void)
{SDA_Output(1);delay1(DELAY_TIME);delay1(DELAY_TIME);SCL_Output(1);delay1(DELAY_TIME);SCL_Output(0);delay1(DELAY_TIME);}/*** @brief I2C发送一个字节* @param cSendByte 需要发送的字节* @retval None*/
void I2CSendByte(unsigned char cSendByte)
{unsigned char  i = 8;while (i--){SCL_Output(0);delay1(DELAY_TIME);SDA_Output(cSendByte & 0x80);delay1(DELAY_TIME);cSendByte += cSendByte;delay1(DELAY_TIME);SCL_Output(1);delay1(DELAY_TIME);}SCL_Output(0);delay1(DELAY_TIME);
}/*** @brief I2C接收一个字节* @param None* @retval 接收到的字节*/
unsigned char I2CReceiveByte(void)
{unsigned char i = 8;unsigned char cR_Byte = 0;SDA_Input_Mode();while (i--){cR_Byte += cR_Byte;SCL_Output(0);delay1(DELAY_TIME);delay1(DELAY_TIME);SCL_Output(1);delay1(DELAY_TIME);cR_Byte |=  SDA_Input();}SCL_Output(0);delay1(DELAY_TIME);SDA_Output_Mode();return cR_Byte;
}//
void I2CInit(void)
{GPIO_InitTypeDef GPIO_InitStructure = {0};GPIO_InitStructure.Pin = GPIO_PIN_7 | GPIO_PIN_6;GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;GPIO_InitStructure.Pull = GPIO_PULLUP;GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_HIGH;HAL_GPIO_Init(GPIOB, &GPIO_InitStructure);
}/**************以上是大赛提供的驱动**************************//***********以下是自己写的对24C02的读写操作******************/unsigned char eeprom_read(unsigned char addr)
{unsigned char dat;I2CStart();I2CSendByte(0xa0);I2CWaitAck();I2CSendByte(addr);I2CWaitAck();I2CStop();I2CStart();I2CSendByte(0xa1);I2CWaitAck();dat = I2CReceiveByte();I2CWaitAck();I2CStop();return dat;
}void eeprom_write(unsigned char addr, unsigned char dat)
{I2CStart();I2CSendByte(0xa0);I2CWaitAck();I2CSendByte(addr);I2CWaitAck();I2CSendByte(dat);I2CWaitAck();I2CStop();
}

main.c:

/* USER CODE BEGIN Header */
/********************************************************************************* @file           : main.c* @brief          : Main program body******************************************************************************* @attention** <h2><center>&copy; Copyright (c) 2023 STMicroelectronics.* All rights reserved.</center></h2>** This software component is licensed by ST under BSD 3-Clause license,* the "License"; You may not use this file except in compliance with the* License. You may obtain a copy of the License at:*                        opensource.org/licenses/BSD-3-Clause********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "adc.h"
#include "tim.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "lcd.h"
#include "badc.h"
#include "stdio.h"
#include "i2c.h"
#include "interrupt.h"
/* 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 */
extern struct keys key[4];
unsigned char adc1_L, adc1_H;
/* 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_TIM3_Init();MX_TIM16_Init();MX_TIM17_Init();MX_ADC1_Init();MX_ADC2_Init();/* USER CODE BEGIN 2 */LCD_Init();LCD_Clear(Black);LCD_SetBackColor(Black);LCD_SetTextColor(White);HAL_TIM_Base_Start_IT(&htim3);/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 */char text[30];unsigned int adc1, adc2;adc1 = getADC(&hadc1);sprintf(text, "    V1:%.2f", adc1 * 3.3 / 4096);LCD_DisplayStringLine(Line4, (unsigned char *)text);adc2 = getADC(&hadc2);sprintf(text, "    V2:%.2f", adc2 * 3.3 / 4096);LCD_DisplayStringLine(Line5, (unsigned char *)text);if(key[0].single_flag) //短按写入{adc1_L = adc1 & 0xff;adc1_H = adc1 >> 8;eeprom_write(1, adc1_L);HAL_Delay(10);eeprom_write(2, adc1_H);key[0].single_flag = 0;}if(key[0].long_flag) //长按读出{char text[30];unsigned int eep_temp = (eeprom_read(2) << 8) + eeprom_read(1);sprintf(text, "    ADC_eep=%.2f", eep_temp * 3.3 / 4096);LCD_DisplayStringLine(Line8, (unsigned char *)text);key[0].long_flag = 0; }}/* USER CODE END 3 */
}/*** @brief System Clock Configuration* @retval None*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct = {0};RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};/** Configure the main internal regulator output voltage*/HAL_PWREx_ControlVoltageScaling(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 = RCC_PLLM_DIV3;RCC_OscInitStruct.PLL.PLLN = 20;RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;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_DIV1;RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK){Error_Handler();}/** Initializes the peripherals clocks*/PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_ADC12;PeriphClkInit.Adc12ClockSelection = RCC_ADC12CLKSOURCE_SYSCLK;if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != 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 *//************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

5.演示效果

eeprom实验

总结

以上就是I2C的配置过程，测试代码以及测试效果
参考的学习视频:【2023蓝桥杯嵌入式组适用】CT117E-M4 新款开发板 3小时省赛模块速成总结
之前的模块配置方法及测试:
【STM32G431RBTx】备战蓝桥杯嵌入式→基本模块→LED
【STM32G431RBTx】备战蓝桥杯嵌入式→基本模块→LCD
【STM32G431RBTx】备战蓝桥杯嵌入式→基本模块→KEY→单击
【STM32G431RBTx】备战蓝桥杯嵌入式→基本模块→KEY→长按(持续响应)以及双击
【STM32G431RBTx】备战蓝桥杯嵌入式→基本模块→TIM→PWM
【STM32G431RBTx】备战蓝桥杯嵌入式→基本模块→ADC