用stm32做主机,8个51单片机做从机实现I2C通信,从机地址怎么规定
时间: 2024-06-06 22:09:51 浏览: 2
从机地址是通过硬件引脚进行设定,每个从机都需要有一个唯一的地址。在 I2C 通信协议中,从机地址是一个 7 位的二进制数字。第一位是总线地址,必须为1,后面6位可以由用户自由设定为 0 或 1。因此,在这种情况下,您可以为每个从机分配不同的 6 位地址,并将其硬编码在从机中。这样,在主机发送消息时,它可以指定要与哪个从机通信,从而确保每个从机都可以被识别和访问。
相关问题
两个stm32F103C8T6分别作I2C从机向主机发送数据
好的,下面是两个STM32F103C8T6分别作为I2C从机向主机发送数据的基本步骤:
1. 配置I2C外设:设置I2C的时钟频率、I2C地址等参数。
2. 配置GPIO口:将SDA和SCL引脚配置为I2C模式。
3. 接收主机的读写请求:在I2C的中断服务函数中,检查接收到的I2C事件,例如接收到了地址匹配事件或接收到了数据。
4. 处理主机的读写请求:如果接收到了读取请求,则向主机发送数据;如果接收到了写入请求,则接收主机发送的数据。
5. 主机向从机发送数据:主机通过I2C总线向从机发送数据,从机接收主机发送的数据。
这里给出两个STM32F103C8T6分别作为I2C从机向主机发送数据的简单示例代码:
从机1:
```c
#include "stm32f10x.h"
#define SLAVE1_ADDRESS 0x50
uint8_t data1 = 0x55;
void I2C1_EV_IRQHandler(void) {
// 检查I2C事件
if (I2C1->SR1 & I2C_SR1_ADDR) {
// 接收到地址匹配事件
uint8_t dummy = I2C1->SR2;
}
if (I2C1->SR1 & I2C_SR1_RXNE) {
// 接收到数据
uint8_t received = I2C1->DR;
}
if (I2C1->SR1 & I2C_SR1_TXE) {
// 发送数据
I2C1->DR = data1;
}
}
int main(void) {
// 配置I2C1外设
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
I2C_InitTypeDef i2c;
i2c.I2C_ClockSpeed = 100000;
i2c.I2C_Mode = I2C_Mode_I2C;
i2c.I2C_DutyCycle = I2C_DutyCycle_2;
i2c.I2C_OwnAddress1 = SLAVE1_ADDRESS;
i2c.I2C_Ack = I2C_Ack_Enable;
i2c.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_Init(I2C1, &i2c);
I2C_Cmd(I2C1, ENABLE);
// 配置GPIO口
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
GPIO_InitTypeDef gpio;
gpio.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
gpio.GPIO_Mode = GPIO_Mode_AF_OD;
gpio.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &gpio);
// 配置I2C中断
NVIC_InitTypeDef nvic;
nvic.NVIC_IRQChannel = I2C1_EV_IRQn;
nvic.NVIC_IRQChannelPreemptionPriority = 0;
nvic.NVIC_IRQChannelSubPriority = 0;
nvic.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&nvic);
I2C_ITConfig(I2C1, I2C_IT_EVT, ENABLE);
while (1);
}
```
从机2:
```c
#include "stm32f10x.h"
#define SLAVE2_ADDRESS 0x60
uint8_t data2 = 0xAA;
void I2C2_EV_IRQHandler(void) {
// 检查I2C事件
if (I2C2->SR1 & I2C_SR1_ADDR) {
// 接收到地址匹配事件
uint8_t dummy = I2C2->SR2;
}
if (I2C2->SR1 & I2C_SR1_RXNE) {
// 接收到数据
uint8_t received = I2C2->DR;
}
if (I2C2->SR1 & I2C_SR1_TXE) {
// 发送数据
I2C2->DR = data2;
}
}
int main(void) {
// 配置I2C2外设
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE);
I2C_InitTypeDef i2c;
i2c.I2C_ClockSpeed = 100000;
i2c.I2C_Mode = I2C_Mode_I2C;
i2c.I2C_DutyCycle = I2C_DutyCycle_2;
i2c.I2C_OwnAddress1 = SLAVE2_ADDRESS;
i2c.I2C_Ack = I2C_Ack_Enable;
i2c.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_Init(I2C2, &i2c);
I2C_Cmd(I2C2, ENABLE);
// 配置GPIO口
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
GPIO_InitTypeDef gpio;
gpio.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
gpio.GPIO_Mode = GPIO_Mode_AF_OD;
gpio.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &gpio);
// 配置I2C中断
NVIC_InitTypeDef nvic;
nvic.NVIC_IRQChannel = I2C2_EV_IRQn;
nvic.NVIC_IRQChannelPreemptionPriority = 0;
nvic.NVIC_IRQChannelSubPriority = 0;
nvic.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&nvic);
I2C_ITConfig(I2C2, I2C_IT_EVT, ENABLE);
while (1);
}
```
以上代码中,从机1和从机2的地址分别是0x50和0x60,你可以根据自己的需求修改。主机通过I2C总线向两个从机发送数据时,需要先发送一个地址字节,然后再发送数据字节。
两个stm32单片机之间的iic通信例程,从机发送主机接收
以下是一个示例代码,用于两个STM32单片之间的IIC通信。在该例程中,一个STM32作为从设备(Slave)发送数据给另一个STM32作为主设备(Master)进行接收。
从设备发送数据给主设备:
```c
#include "stm32f4xx.h"
#include "stm32f4xx_i2c.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#define I2C_ADDRESS 0x08 // 主设备地址
I2C_InitTypeDef I2C_InitStruct;
GPIO_InitTypeDef GPIO_InitStruct;
void I2C_Configuration(void)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStruct.GPIO_OType = GPIO_OType_OD;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOB, &GPIO_InitStruct);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource8, GPIO_AF_I2C1);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource9, GPIO_AF_I2C1);
I2C_DeInit(I2C1);
I2C_InitStruct.I2C_ClockSpeed = 100000;
I2C_InitStruct.I2C_Mode = I2C_Mode_I2C;
I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2;
I2C_InitStruct.I2C_OwnAddress1 = 0x07; // 从设备地址
I2C_InitStruct.I2C_Ack = I2C_Ack_Enable;
I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_Init(I2C1, &I2C_InitStruct);
I2C_Cmd(I2C1, ENABLE);
}
void I2C_SendData(uint8_t* data, uint8_t dataLength)
{
while (I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
I2C_GenerateSTART(I2C1, ENABLE);
while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, I2C_ADDRESS, I2C_Direction_Transmitter);
while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
for (uint8_t i = 0; i < dataLength; i++)
{
I2C_SendData(I2C1, data[i]);
while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
}
I2C_GenerateSTOP(I2C1, ENABLE);
}
int main(void)
{
uint8_t data[] = "Hello";
I2C_Configuration();
while (1)
{
I2C_SendData(data, sizeof(data));
delay(500);
}
}
```
主设备接收从设备发送的数据:
```c
#include "stm32f4xx.h"
#include "stm32f4xx_i2c.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_usart.h"
#define I2C_ADDRESS 0x07 // 从设备地址
I2C_InitTypeDef I2C_InitStruct;
GPIO_InitTypeDef GPIO_InitStruct;
USART_InitTypeDef USART_InitStruct;
void I2C_Configuration(void)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStruct.GPIO_OType = GPIO_OType_OD;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOB, &GPIO_InitStruct);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource8, GPIO_AF_I2C1);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource9, GPIO_AF_I2C1);
I2C_DeInit(I2C1);
I2C_InitStruct.I2C_ClockSpeed = 100000;
I2C_InitStruct.I2C_Mode = I2C_Mode_I2C;
I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2;
I2C_InitStruct.I2C_OwnAddress1 = 0x08; // 主设备地址
I2C_InitStruct.I2C_Ack = I2C_Ack_Enable;
I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_Init(I2C1, &I2C_InitStruct);
I2C_Cmd(I2C1, ENABLE);
}
void USART_Configuration(void)
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_USART1);
USART_DeInit(USART1);
USART_InitStruct.USART_BaudRate = 9600;
USART_InitStruct.USART_WordLength = USART_WordLength_8b;
USART_InitStruct.USART_StopBits = USART_StopBits_1;
USART_InitStruct.USART_Parity = USART_Parity_No;
USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
USART_Init(USART1, &USART_InitStruct);
USART_Cmd(USART1, ENABLE);
}
void I2C_ReceiveData(void)
{
uint8_t receivedData[10];
uint8_t dataLength = 0;
while (I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
I2C_AcknowledgeConfig(I2C1, ENABLE);
I2C_GenerateSTART(I2C1, ENABLE);
while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, I2C_ADDRESS, I2C_Direction_Receiver);
while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
while (dataLength < sizeof(receivedData))
{
if (I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED))
{
receivedData[dataLength++] = I2C_ReceiveData(I2C1);
}
}
I2C_AcknowledgeConfig(I2C1, DISABLE);
I2C_GenerateSTOP(I2C1, ENABLE);
for (uint8_t i = 0; i < dataLength; i++)
{
while (!USART_GetFlagStatus(USART1, USART_FLAG_TXE));
USART_SendData(USART1, receivedData[i]);
}
}
int main(void)
{
I2C_Configuration();
USART_Configuration();
while (1)
{
I2C_ReceiveData();
delay(500);
}
}
```
在从设备中,我们使用`I2C_SendData()`函数发送数据给主设备。首先,我们等待IIC总线空闲,然后生成START信号,接着发送主设备地址和写入位,然后通过循环发送数据字节。最后,我们生成STOP信号结束传输。
在主设备中,我们使用`I2C_ReceiveData()`函数接收从设备发送的数据。首先,我们等待IIC总线空闲,然后生成START信号,接着发送从设备地址和读取位。然后,我们循环接收数据字节,并通过USART发送到串口进行打印。
请注意:以上示例代码是基于STM32F4系列的,使用了STM32标准外设库(Standard Peripherals Library)。如果你使用其他型号的STM32单片机或者使用了不同的开发库,可能需要进行相应的调整。
希望这个例程对你有所帮助!如果还有其他问题,请随时提问。
相关推荐
![7z](https://img-home.csdnimg.cn/images/20210720083312.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)