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。
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SDA
OLED_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0x40
MyI2C_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 off
Oled_Write_Cmd(0x00);//---set low column address
Oled_Write_Cmd(0x10);//---set high column address
Oled_Write_Cmd(0x40);//--set start line address
Oled_Write_Cmd(0xB0);//--set page address
Oled_Write_Cmd(0x81); // contract control
Oled_Write_Cmd(0xFF);//--128
Oled_Write_Cmd(0xA1);//set segment remap
Oled_Write_Cmd(0xA6);//--normal / reverse
Oled_Write_Cmd(0xA8);//--set multiplex ratio(1 to 64)
Oled_Write_Cmd(0x3F);//--1/32 duty
Oled_Write_Cmd(0xC8);//Com scan direction
Oled_Write_Cmd(0xD3);//-set display offset
Oled_Write_Cmd(0x00);//
Oled_Write_Cmd(0xD5);//set osc division
Oled_Write_Cmd(0x80);//
Oled_Write_Cmd(0xD8);//set area color mode off
Oled_Write_Cmd(0x05);//
Oled_Write_Cmd(0xD9);//Set Pre-Charge Period
Oled_Write_Cmd(0xF1);//
Oled_Write_Cmd(0xDA);//set com pin configuartion
Oled_Write_Cmd(0x12);//
Oled_Write_Cmd(0xDB);//set Vcomh
Oled_Write_Cmd(0x30);//
Oled_Write_Cmd(0x8D);//set charge pump enable
Oled_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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0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xFF,0xFF,0x81,0x81,
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0xB0,0x30,0x30,0x30,0x30,0x30,0x30,0x30,0xF0,0xF0,0xB3,0x33,0x36,0x36,0x16,0x1E,
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0xC0,0xC0,0xC0,0xC0,0xC0,0xC0,0xC0,0xC1,0xC1,0x43,0x63,0x63,0x63,0x31,0x31,0x30,
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0xF0,0xF0,0xF0,0xF0,0xD8,0xD8,0xD8,0xDC,0xFC,0xF6,0xF6,0xE3,0xE3,0xE3,0x63,0x63,
0x63,0x62,0x66,0x36,0x36,0x36,0x1E,0x1E,0x0E,0x0E,0x06,0x07,0x03,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
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 off
Oled_Write_Cmd(0x00);//---set low column address
Oled_Write_Cmd(0x10);//---set high column address
Oled_Write_Cmd(0x40);//--set start line address
Oled_Write_Cmd(0xB0);//--set page address
Oled_Write_Cmd(0x81); // contract control
Oled_Write_Cmd(0xFF);//--128
Oled_Write_Cmd(0xA1);//set segment remap
Oled_Write_Cmd(0xA6);//--normal / reverse
Oled_Write_Cmd(0xA8);//--set multiplex ratio(1 to 64)
Oled_Write_Cmd(0x3F);//--1/32 duty
Oled_Write_Cmd(0xC8);//Com scan direction
Oled_Write_Cmd(0xD3);//-set display offset
Oled_Write_Cmd(0x00);//
Oled_Write_Cmd(0xD5);//set osc division
Oled_Write_Cmd(0x80);//
Oled_Write_Cmd(0xD8);//set area color mode off
Oled_Write_Cmd(0x05);//
Oled_Write_Cmd(0xD9);//Set Pre-Charge Period
Oled_Write_Cmd(0xF1);//
Oled_Write_Cmd(0xDA);//set com pin configuartion
Oled_Write_Cmd(0x12);//
Oled_Write_Cmd(0xDB);//set Vcomh
Oled_Write_Cmd(0x30);//
Oled_Write_Cmd(0x8D);//set charge pump enable
Oled_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 mode
Oled_Write_Cmd (0x02); //page addressing mode
for(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
这里要说一点,就是stm32可以作为主机或者从机是用。实验里面,只要stm32产生起始条件,我们把stm32当做主机使用,因此从机模式里面我们压根就没有管,保持他的默认形式就行。
最后我想说的是,无论是HAL还是标准库,都可以实现我们的需求。标准库写的麻烦,但是可以染你在写程序的时候更多关注于手册的细节,HAL库看似比较简单方便,但是他是高度集成的,里面很多细节不是那么容易看出来的,因为HAL库封装的程度太高了,各取所需吧。