2 stm32之间的通信

Question

我正在尝试用I2C传送2个STM32。我的配置如下：

7位寻址模式（无双地址，仅OAR1）

100khz的速度

启用ACK（在从站上）

ACK被禁用（在主设备上，因为在任何时候主设备/从设备之间只传输1个字节）

在主/从，使用GPIOB（PB6）作为SCL作为AF和GPIOB（PB7）作为SDA作为AF。问题出在哪里？

主码：

#include "stm32f10x.h" // Device header #include "delay.h"

void pinConfig(void);

void i2c_Master_Config(void);

void sendData(uint8_t data);

int main() {

    delay_init();
    pinConfig();
    i2c_Master_Config();

    while(1)
    {
        uint8_t butonState=GPIOA->IDR & 0x00001000; 
        sendData(0x68,butonState);
        delay_ms(10);
    }
}

void pinConfig() {

    RCC->APB1ENR |=1<<21;//Enable I2C 1 clock
    RCC->APB2ENR   |=1<<2;//Enable GPIOA clock
    RCC->APB2ENR   |=1<<3;//Enable GPIOB clock 
    RCC->APB2ENR   |=1<<0;//Enable AFIO clock

    GPIOA->CRL |= 0x00008000; //PA3 button pull-down 
    GPIOB->CRL = 0xFF000000; //SCL and SDA  AF Open Drain  SCL => PB6  SDA     =>PB7
}

void i2c_Master_Config() {

    I2C1->CR2    |=1<<5; //36 Mhz peripheral clock.
    I2C1->CR2    |=1<<2; //36 Mhz peripheral clock.
    I2C1->CCR     =0x28;//100 khz clock  
    I2C1->TRISE   =9;//1/8MHZ= 125 ns  => 1000ns/125ns =8  => 8+1 =9
    I2C1->CR1     |=(1<<0);//Peripheral enable..
}

void sendData(uint8_t data) {
    volatile int temp;

    while(I2C1->SR2 &(1<<1));//BUSY bit.
    I2C1->CR1  |=1<<8;//START bit.
    while(!(I2C1->SR1 & (1<<0))); //wait until start flag is set

    I2C1->DR  = slaveAdres<<1;//7 bit adress.

    while(!(I2C1->SR1 &(1<<1)));//wait until addr flag is set
    gecici=I2C1->SR2;//clear addr flag.

    I2C1->DR = data; 
    while (!(I2C1->SR1 & (1<<7))){} //wait until txe is set

    while (!(I2C1->SR1 & (1<<2)));//BTF(Byte transfer finished)=1 . 
    I2C1->CR1 |= 1<<9;//STOP bit.
    I2C1->CR1     &=~(1<<0);//Peripheral disable.
}

奴隶代码：

#include "stm32f10x.h" // Device header

void pinConfig(void);

void i2c_Slave_Config(void);

uint8_t readData(void);

uint8_t data;

int main()
{

    pinConfig();
    i2c_Slave_Config();

    while(1)
    {
        data=readData();

        if(data==0)
            GPIOB->BSRR |=1<<3;
        else if(data==1)
            GPIOB->BRR  |=1<<3;
    }
}

void pinConfig()
{

    RCC->APB1ENR |=1<<21;//I2C 1 Clock Aktif.
    RCC->APB2ENR   |=1<<2;//Enable GPIOA clock
    RCC->APB2ENR   |=1<<3;//Enable GPIOB clock 
    RCC->APB2ENR   |=1<<0;//Enable AFIO clock

    GPIOA->CRL |= 0x00002000; //PA3 led.
    GPIOB->CRL = 0xFF000000; //SCL and SDA  AF Open Drain  SCL => PB6  SDA   =>PB7
    GPIOA->BSRR |=1<<3;//Turn off the led.
}

void i2c_Slave_Config() {

    RCC->APB1ENR |=1<<21;//I2C 1 Clock Enable.
    I2C1->CR2    |=1<<5; //36 Mhz peripheral clock.
    I2C1->CR2    |=1<<2; //36 Mhz peripheral clock.
    I2C1->CCR     =0x28;//100 khz clock  
    I2C1->OAR1    &=~(1<<15);//7-bit slave adress.
    I2C1 ->CR1     |= 1<<10;//ACK enable.

    //0x68 Slave Adress Configured.    
    I2C1 ->OAR1   &=~(1<<1);
    I2C1 ->OAR1   &=~(1<<2);
    I2C1 ->OAR1   &=~(1<<3);
    I2C1 ->OAR1   &=~(1<<5);
    I2C1 ->OAR1   |=(1<<4);
    I2C1 ->OAR1   |=(1<<6);
    I2C1 ->OAR1   |=(1<<7);
    //0x68 Slave Adress Configured.
}

uint8_t readData()
{
    volatile int temp;
    uint8_t data;

    I2C1->CR1     |=(1<<0);//Peripheral enable.

    while(I2C1->SR2 &(1<<1));//BUSY bit.
    I2C1->CR1  |=1<<8;//START bit.
    while(!(I2C1->SR1 & (1<<0))); // wait until start flag is set.

    while(!(I2C1->SR1 &(1<<1)));// wait until addr flag is set
    temp=I2C1->SR2;//clear addr .

    while (!(I2C1->SR1 & (1<<6))){} // wait until rxne is set
    data=I2C1->DR;

    while (!(I2C1->SR1 & (1<<4))){} // wait until STOPF is set
    gecici=I2C1->SR1;

    I2C1->SR1 |=1<<9;

    I2C1->CR1     &=~(1<<0);//Peripheral disable.
    return data;
}

地址不匹配。我没有看到对示波器上的SDA和SCL信号的任何响应。我在每条线上使用4.7kΩ将SCL和SDA拉到3.3v。（STM32F103C6）。

Answer 1

现在，在i2c_Master_Config()的主启动时启用了主I2C模块，然后在sendData()结束时禁用，并且再也没有启用。

从机I2C模块在开始时启用，在qazxsw poi结束时禁用。

这足以破坏沟通。应始终启用I2C外设模块（直到您了解何时应禁用它）。

附：对不起，我没有深入分析你的代码 - 很多“魔术数字”而不是助记符位名称使分析变得困难。也许，还有其他错误。