基于stm32f103系列的简单软件I2C和硬件I2C通讯

这篇文章主要分为三个部分来阐述，分别是I2C的基本知识，软件I2C通讯，硬件I2C通讯。I2C的基本知识这一块，部分讲解以及图表来自b站江科大的up，很感谢这位up，大家可以关注一波。操作实现的时候，up使用的是标准库讲解，我是用是HAL库，但都可以实现。

一、I2C的基本知识

1.基本的三种通讯方式

学过通讯的同学都知道，基本的通讯方式有单工，半双工，全双工。那么这三种工作方式有啥区别吗？我给大家举个例子：

单工通讯就好比象棋里面的“卒”，卒有啥特性？没错，一条路走到黑，不走回头路，说白了，这种通讯方式就是“有去无回”。我只知道我可以通过这条线发过去，但是我没法通过这条线反馈信息。

半双工通讯就好比你在狭窄的山路上开车，你可以开入山里面，也可以开出山里面，但是山路狭窄，在同一时刻同一路段只能允许一辆车通过。所以你你要想开入山里面，就必须等到出山的车先开出来；要想开出山里面，就必须让开入山里面的车先开进去。说白了，就是说，你可以出入山里，但是一定要确保你在开车的过程中，山路上没有相反方向的车堵住你。所以半双工在同一时刻，只能有一个方向的通讯。等到这个方向通讯完成，你才可以选择下一次通讯的方向。

全双工通讯就好比我们现在的公路，随时随地，有来有回，去的车道完全不对回来的车道有影响，大家各走各的。

这三种通道各自有各自的优劣与使用场景，感兴趣的同学可以自己百度百度。我们今天要说的就是I2C就是半双工通讯。

2.I2C通讯规则

①

起始条件:在SCL高电平的时候，SDA由高电平变为低电平

②

终止条件:在SCL高电平的时候，SDA由高电平变为低电平

③

发送一个字节:SCL低电平期间，主机将数据位依次放到SDA线上（高位先行），然后释放SCL，从机将在SCL高电平期间读取数据位，所以SCL高电平期间SDA不允许有数据变化，依次循环上述过程8次，即可发送一个字节

④

接收一个字节:SCL低电平期间，从机将数据位依次放到SDA线上（高位先行），然后释放SCL，主机将在SCL高电平期间读取数据位，所以SCL高电平期间SDA不允许有数据变化，依次循环上述过程8次，即可接收一个字节（主机在接收之前，需要释放SDA，就是要让SDA=1）

⑤

发送应答:主机在接收完一个字节之后，在下一个时钟发送一位数据，数据0表示应答，数据1表示非应答。

⑥

接收应答:主机在发送完一个字节之后，在下一个时钟接收一位数据，判断从机是否应答，数据0表示应答，数据1表示非应答（主机在接收之前，需要释放SDA）。

请大家看清楚接受和发送的对象是谁，不要混淆了。

3.硬件电路

第一张图告诉我们，所有的从机设备都和主机的时序一样，因此属于同步时序。主机的SDA连接着从机的SDA，这是一张典型的一主多从模型图。主机想要和谁通讯就，只需要输入对应的从机地址就行了。图中的两个R是为了保护电路的，具体咋保护的呢？

按道理说，只要我们按照正常的时序，就可以实现主机的SDA输出，从机的SDA输入；从机的SDA输出，主机的SDA输入，这没问题。但是如果时序没有协调好，有可能会出现一方的SDA输出1，一方的SDA输出0，这样就相当于高低电平直接接在一起，不就短路了吗？

因此I2C的设计规定，禁止所有的设备（无论是主机还是从此，内部的SDA,SCL电路都如第二张图所示）输出强上拉的高电平，采用外置弱上拉的电阻加开路输出的电路结构，这样就不用担心短路的问题了，如上图所示，在输入时，无论是SCL还是SDA的电路，输入高低电平都无影响。但是在输出是，因为SDA和SCL都是开漏模式，因此当输出低电平时，直接导通；输出高电平时，被截断处于浮空状态。但是浮空状态不稳定容易受到干扰，因此有外接一个电阻R，相当于让浮空的引脚与电阻相连，完成弱上拉，变相的输出高电平。

下面我以主机SDA为例，给大家画一下等效图

无论是主机还是从机，SDA和SCL都可以这样简化。如果你想了解为什么可以这样的简化，，你可以去b站上自己学一下场效应管的知识，再结合第一第二张图片的电路，你就懂了，这里我就不细说效应管的知识了。

4.三种基本的I2C时序通讯

①指定地址写：指定地址写入一个字节

如果想要写入多个字节，在终止条件前面的应答位应答，并且再次重复主机发送字节写内容及应答即可，直到不想发送，然后在写入终止条件。

②当前地址读

如果想要读入多个字节，在终止条件前面的应答位应答，并且再次重复从机发送字节写内容及应答即可，直到不想发送，然后在写入终止条件。

当前地址指针：就是说这个指针目前指向那个寄存器。当我们写的时候，会在该指针的位置写入，写完后自动加1，向下移动；当我们读的时候，会在该指针的位置读出，读完后自动加1，向下移动。

③指定地址读：相当于把指定地址写的终止条件去掉，然后和当前地址读结合起来。比如说我在指定地址写的时候，选好了从机的8位储存器地址，那么当前地址指针就要指向这里，我们就在这里写，接着应答，然后开始执行当前地址读的序列，那么就可以再当前的位置（也就是我们指定的写入地址的位置）读取出来数据。

二、软件I2C通讯

1.前提准备

这里还是依据51单片机的I2C模拟通讯来进行改编，不熟悉的话，可以回看一下51模拟I2C通讯实现OLED显示图片

2.代码部分（运行出来是一条蛇）

这里我们想要用PB7端口模拟SDA,PB6端口模拟SCL,同时根据第一部分介绍，我们应该知道SDA,SCL都应该是开漏模式，所以我们的PB7端口和PB6端口都会配置成开漏模式。

#include "main.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#define OLED_I2C_SCL_CLK()		__HAL_RCC_GPIOB_CLK_ENABLE()
#define OLED_I2C_SCL_GPIO  		GPIOB
#define OLED_I2C_SCL_PIN   		GPIO_PIN_6#define OLED_I2C_SDA_CLK()   	__HAL_RCC_GPIOB_CLK_ENABLE()
#define OLED_I2C_SDA_GPIO  		GPIOB
#define OLED_I2C_SDA_PIN   		GPIO_PIN_7#define OLED_SCL_RESET() 			HAL_GPIO_WritePin(OLED_I2C_SCL_GPIO,OLED_I2C_SCL_PIN,GPIO_PIN_RESET)  //SCL
#define OLED_SCL_SET() 				HAL_GPIO_WritePin(OLED_I2C_SCL_GPIO,OLED_I2C_SCL_PIN,GPIO_PIN_SET)#define OLED_SDA_RESET() 			HAL_GPIO_WritePin(OLED_I2C_SDA_GPIO,OLED_I2C_SDA_PIN,GPIO_PIN_RESET)  //SDA
#define OLED_SDA_SET() 				HAL_GPIO_WritePin(OLED_I2C_SDA_GPIO,OLED_I2C_SDA_PIN,GPIO_PIN_SET)/* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
void MyI2C_Start(void)//起始条件
{OLED_SCL_SET();OLED_SDA_SET();OLED_SDA_RESET();OLED_SCL_RESET();}void MyI2C_Stop(void)//终止条件
{OLED_SCL_SET() ;OLED_SDA_RESET();OLED_SDA_SET();
}void MyI2C_SendByte(uint8_t Byte)//发送一个字节
{uint8_t i;uint8_t m,da;da = Byte;OLED_SCL_RESET();for(i = 0; i < 8; i++)		{m = da;m = m&0x80;if(m == 0x80)OLED_SDA_SET();else OLED_SDA_RESET();da = da << 1;OLED_SCL_SET();OLED_SCL_RESET();}
}char MyI2C_SendAck()//发送应答
{char flag;OLED_SDA_SET();//释放SDAOLED_SCL_SET();flag=	HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_7);OLED_SCL_RESET();return flag;
}/* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
void Oled_Write_Cmd(char dataCmd)//发送一个写命令字节
{MyI2C_Start();MyI2C_SendByte(0x78);MyI2C_SendAck();	MyI2C_SendByte(0x00);MyI2C_SendAck();	MyI2C_SendByte(dataCmd); MyI2C_SendAck();	MyI2C_Stop();
}void Oled_Write_Data(char dataData)//发送一个写数据字节
{MyI2C_Start();//起始条件MyI2C_SendByte(0x78);//发送从机地址MyI2C_SendAck();//应答MyI2C_SendByte(0x40);//开启写入命令0x00或写入数据0x40MyI2C_SendAck();	//应答MyI2C_SendByte(dataData);//写入具体的命令或者数据MyI2C_SendAck();MyI2C_Stop();//IIC结束
}void OLED_Init(void)
{Oled_Write_Cmd(0xAE);//--display offOled_Write_Cmd(0x00);//---set low column addressOled_Write_Cmd(0x10);//---set high column addressOled_Write_Cmd(0x40);//--set start line address  Oled_Write_Cmd(0xB0);//--set page addressOled_Write_Cmd(0x81); // contract controlOled_Write_Cmd(0xFF);//--128   Oled_Write_Cmd(0xA1);//set segment remap Oled_Write_Cmd(0xA6);//--normal / reverseOled_Write_Cmd(0xA8);//--set multiplex ratio(1 to 64)Oled_Write_Cmd(0x3F);//--1/32 dutyOled_Write_Cmd(0xC8);//Com scan directionOled_Write_Cmd(0xD3);//-set display offsetOled_Write_Cmd(0x00);//Oled_Write_Cmd(0xD5);//set osc divisionOled_Write_Cmd(0x80);//Oled_Write_Cmd(0xD8);//set area color mode offOled_Write_Cmd(0x05);//Oled_Write_Cmd(0xD9);//Set Pre-Charge PeriodOled_Write_Cmd(0xF1);//Oled_Write_Cmd(0xDA);//set com pin configuartionOled_Write_Cmd(0x12);//Oled_Write_Cmd(0xDB);//set VcomhOled_Write_Cmd(0x30);//Oled_Write_Cmd(0x8D);//set charge pump enableOled_Write_Cmd(0x14);//Oled_Write_Cmd(0xAF);//--turn on oled panel	
}/* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
void Oled_Screen_Clear(void){unsigned char i,n;for(i=0;i<8;i++){Oled_Write_Cmd(0xb0+i);              Oled_Write_Cmd(0x00);                 Oled_Write_Cmd(0x10);                 for(n=0;n<128;n++)Oled_Write_Data(0x00); 			}	
}unsigned char bmpImager[] = {/*--  调入了一幅图像：D:\无标题.bmp  --*/
/*--  宽度x高度=128x64  --128x8x8*/
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0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
};void Oled_Show_Image(unsigned char *image)
{unsigned char i; unsigned int j;for(i=0;i<8;i++){Oled_Write_Cmd(0xB0 + i);//page0--page7//每个page从0列Oled_Write_Cmd(0x00);Oled_Write_Cmd(0x10);//0到127列，依次写入0，每写入数据，列地址自动偏移for(j = 128 * i; j<(128 * (i+1));j++){Oled_Write_Data(image[j]);}}
}
/* USER CODE END PM *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV *//* 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();/* USER CODE BEGIN 2 */OLED_Init();//2. 选择一个位置//2.1 确认页寻址模式Oled_Write_Cmd(0x20);Oled_Write_Cmd(0x02);Oled_Screen_Clear();Oled_Show_Image(bmpImager);/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}

3.stm32cube配置

SYS,RCC照旧

GPIO的配置如下图，PB6,7配置一样

三、硬件I2C通讯

1.前提准备

我们的32单片机是有I2C外设的，而51里面没有I2C外设，因此，我们的32单片机既可以用硬件I2C通讯，也可以模拟I2C通讯。这里我们要实现的是利用32单片机和HAL库重新做一下OLED显示图片，oled的操作说明和图片的操作细节可以再http://t.csdnimg.cn/Bk61c和http://t.csdnimg.cn/A8htshttp://t.csdnimg.cn/Bk61c和里面看一下。

我们使用硬件I2C后，可以直接调用直接调用库函数来控制寄存器，让寄存器控制硬件电路的状态从而来控制SDA和SCL的时序。诸如起始终止条件，接受发送字节，应答之类的，我们不用软件I2C那样，自己手动控制SDA和SCL的时序，只需要用库函数即可控制硬件，调制出我们需要的时序。那么既然硬件那么好，为啥还要软件I2C?我玩个梗，加个外设，可以，得加钱。

2.代码部分（运行出来是女孩头像）

先说一下我们要用的函数

HAL_I2C_Mem_Write(I2C_HandleTypeDef *hi2c, uint16_t DevAddress, uint16_t MemAddress, uint16_t MemAddSize, uint8_t *pData, uint16_t Size, uint32_t Timeout)

它的作用是以阻塞方式将一定数量的数据写入特定的内存地址，下面看看参数

参数一：I2C_HandleTypeDef *hi2c，选择哪一个I2C通道的地址

参数二：uint16_t DevAddress，目标器件的地址，七位地址必须左对齐，外加最后一位读写位

参数三：uint16_t MemAddress，目标器件的目标寄存器地址或者指令控制字

参数四：uint16_t MemAddSize，目标器件内部寄存器地址数据长度及一个数据有多大，这里可以选择8位或者16位

参数五：uint8_t *pData，待写的数据首地址

参数六：uint16_t Size，待写的数据长度

参数七：uint32_t Timeout，超时时间返回值：HAL_StatusTypeDef，HAL状态（OK，busy，ERROR，TIMEOUT）

沿着51单片机显示图片的程序，我们继续修改

#include "main.h"
#include "i2c.h"
#include "gpio.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 */
void Oled_Write_Cmd(uint8_t dataCmd)
{HAL_I2C_Mem_Write(&hi2c1, 0x78, 0x00, I2C_MEMADD_SIZE_8BIT,&dataCmd, 1, 0xff);
}void Oled_Write_Data(uint8_t dataData)
{HAL_I2C_Mem_Write(&hi2c1, 0x78, 0x40, I2C_MEMADD_SIZE_8BIT,&dataData, 1, 0xff);
}void Oled_Init(void){Oled_Write_Cmd(0xAE);//--display offOled_Write_Cmd(0x00);//---set low column addressOled_Write_Cmd(0x10);//---set high column addressOled_Write_Cmd(0x40);//--set start line address  Oled_Write_Cmd(0xB0);//--set page addressOled_Write_Cmd(0x81); // contract controlOled_Write_Cmd(0xFF);//--128   Oled_Write_Cmd(0xA1);//set segment remap Oled_Write_Cmd(0xA6);//--normal / reverseOled_Write_Cmd(0xA8);//--set multiplex ratio(1 to 64)Oled_Write_Cmd(0x3F);//--1/32 dutyOled_Write_Cmd(0xC8);//Com scan directionOled_Write_Cmd(0xD3);//-set display offsetOled_Write_Cmd(0x00);//Oled_Write_Cmd(0xD5);//set osc divisionOled_Write_Cmd(0x80);//Oled_Write_Cmd(0xD8);//set area color mode offOled_Write_Cmd(0x05);//Oled_Write_Cmd(0xD9);//Set Pre-Charge PeriodOled_Write_Cmd(0xF1);//Oled_Write_Cmd(0xDA);//set com pin configuartionOled_Write_Cmd(0x12);//Oled_Write_Cmd(0xDB);//set VcomhOled_Write_Cmd(0x30);//Oled_Write_Cmd(0x8D);//set charge pump enableOled_Write_Cmd(0x14);//Oled_Write_Cmd(0xAF);//--turn on oled panel		
}void Oled_Screen_Clear(void){char i,n;Oled_Write_Cmd (0x20);                    //set memory addressing modeOled_Write_Cmd (0x02);                    //page addressing modefor(i=0;i<8;i++){Oled_Write_Cmd(0xb0+i);               //éè??ò3μ??·￡¨0~7￡?Oled_Write_Cmd(0x00);                 //éè????ê??????aáDμíμ??·Oled_Write_Cmd(0x10);                 //éè????ê??????aáD??μ??·   for(n=0;n<128;n++)Oled_Write_Data(0x00); 			}	
}unsigned char bmpImager[] = {/*--  调入了一幅图像：D:\无标题.bmp  --*/
/*--  宽度x高度=128x64  --128x8x8*/
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0xF0,0x08,0x0C,0x04,0x06,0x06,0x0C,0x04,0x0C,0xFC,0x1C,0x74,0xFC,0xF8,
0xF0,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x01,0x07,0x04,0x88,0xF8,0x08,0x08,0x0C,0x06,0x01,0x00,0x00,0x01,0x1F,
0x7F,0xFF,0xDC,0xF8,0xE0,0xC0,0x40,0xC0,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xE0,0x10,0x18,0x08,0x0C,
0x04,0x04,0x06,0x02,0x01,0x01,0x00,0x00,0x00,0x00,0xFF,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x3F,0x60,0xC0,0x80,0x80,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x3F,0xE0,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,
0x03,0x06,0x1C,0xF0,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x07,0xFC,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x08,0x88,0xE8,0x38,0x0E,0x09,0x08,
0x08,0x88,0xE8,0x18,0x08,0x08,0x08,0x00,0x00,0xFF,0x89,0x89,0x89,0xFF,0x00,0xFF,
0x89,0x89,0x89,0x89,0xFF,0x00,0x00,0x04,0x04,0x84,0x74,0x6F,0xA4,0x24,0x24,0x24,
0x24,0xA4,0x64,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x80,0xF0,0x1F,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x7F,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x10,0x10,0x10,0x08,0x09,0x09,0x06,0x06,
0x06,0x05,0x08,0x08,0x10,0x10,0x00,0x00,0x0C,0x03,0x10,0x10,0x10,0x1F,0x18,0x07,
0x00,0x00,0x10,0x10,0x1F,0x00,0x10,0x08,0x06,0x11,0x10,0x08,0x09,0x0A,0x06,0x06,
0x0B,0x08,0x10,0x10,0x10,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xF0,
0x1E,0x03,0x00,0x00,0xC0,0x60,0x30,0x0C,0x04,0x06,0x02,0x01,0x01,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x03,
0x1E,0x60,0x78,0x0F,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,};void Oled_Show_Image(unsigned char *image)
{unsigned char i; unsigned int j;for(i=0;i<8;i++){Oled_Write_Cmd(0xB0 + i);//page0--page7//每个page从0列Oled_Write_Cmd(0x00);Oled_Write_Cmd(0x10);//0到127列，依次写入0，每写入数据，列地址自动偏移for(j = 128 * i; j<(128 * (i+1));j++){Oled_Write_Data(image[j]);}}
}/* 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_I2C1_Init();/* USER CODE BEGIN 2 *///1. OLED初始化Oled_Init();//2. 选择一个位置//2.1 确认页寻址模式Oled_Write_Cmd(0x20);Oled_Write_Cmd(0x02);Oled_Screen_Clear();Oled_Show_Image(bmpImager);/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}

3.stm32cube的配置

SYS,RCC照旧不变。I2C1里面如下图选择