i2c1从机中断接收发送数据

1、将i2c1设置为从机模式，与树莓派连接。树莓派发送或者读取数据，gd32中断触发，从而接收数据或者向主机发送数据。
2、关于代码的宏定义配置
Application目录的Makefile中 ENABLE_I2C_TEST = yes才会编译I2C1的相关代码。
同时修改i2c.h文件，定义I2C1_MODE为I2C1_MODE_SLAVE，编译烧录后，i2c1即为从机模式。

#define I2C1_MODE                   I2C1_MODE_SLAVE

3、i2c1从机设置代码，i2c.c中

void i2c1_slave_config(void)
{
    /* enable GPIOB clock */
    rcu_periph_clock_enable(RCU_GPIOB);
    /* enable I2C1 clock */
    rcu_periph_clock_enable(RCU_I2C1);
    /* connect PB10 to I2C1_SCL */
    /* connect PB11 to I2C2_SDA */
    gpio_init(GPIOB, GPIO_MODE_AF_OD, GPIO_OSPEED_50MHZ, GPIO_PIN_10 | GPIO_PIN_11);//配置PB10,PB11为复用功能

    /* configure I2C clock */
    i2c_clock_config(I2C1, I2C1_SPEED, I2C_DTCY_2);
    /* configure I2C address */
    i2c_mode_addr_config(I2C1, I2C_I2CMODE_ENABLE, I2C_ADDFORMAT_7BITS, I2C1_OWN_ADDRESS7);
    /* enable I2C1 */
    i2c_enable(I2C1);
    /* enable acknowledge */
    i2c_ack_config(I2C1, I2C_ACK_ENABLE);

    nvic_priority_group_set(NVIC_PRIGROUP_PRE1_SUB3);
    nvic_irq_enable(I2C1_EV_IRQn, 0, 2);
    nvic_irq_enable(I2C1_ER_IRQn, 0, 1);
    /* enable the I2C1 interrupt */
    i2c_interrupt_enable(I2C1, I2C_INT_ERR);
    i2c_interrupt_enable(I2C1, I2C_INT_BUF);
    i2c_interrupt_enable(I2C1, I2C_INT_EV);

}

4、中断处理函数，gd32f30x_it.c中修改

#if I2C1_MODE == I2C1_MODE_SLAVE
/*!
    \brief      I2C1 event handle function
    \param[in]  none
    \param[out] none
    \retval     none
*/
void I2C1_EV_IRQHandler(void)
{
    I2C1_EventIRQ_Handler();
}

/*!
    \brief      I2C1 error handle function
    \param[in]  none
    \param[out] none
    \retval     none
*/
void I2C1_ER_IRQHandler(void)
{
    I2C1_ErrorIRQ_Handler();
}
#endif

5、 I2C1_EventIRQ_Handler()、I2C1_ErrorIRQ_Handler() 在i2c.c定义

volatile uint8_t        i2c_txbuffer[4] = {0x98,0x78,0x67,0xff};
volatile uint8_t        i2c_rxbuffer[128];
volatile uint16_t       i2c_rx_num;
volatile uint16_t       i2c_tx_num;
static   uint8_t        isfirst = 0;

static void send_i2c_data(uint8_t *p_buff,uint16_t len)
{

    printf("get read command ");
    print_register_value(p_buff,len);

}


/*!
    \brief      handle I2C1 event interrupt request
    \param[in]  none
    \param[out] none
    \retval     none
*/
void I2C1_EventIRQ_Handler(void)
{
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_ADDSEND)) {
        /* clear the ADDSEND bit */
        if (isfirst == 0)
        {
            isfirst = 1;
            i2c_rx_num = 0; 
        }
        else
        {
            isfirst = 0;
            i2c_tx_num = 0;
            send_i2c_data(i2c_rxbuffer,i2c_rx_num);
        }
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_ADDSEND);
    } else if((i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_TBE)) && (!i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_AERR))) {
        
        /* send a data byte */ 
        //printf("now send data  %d: \r\n",i2c_tx_num);
        i2c_data_transmit(I2C1, i2c_txbuffer[i2c_tx_num++]);
    } else if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_RBNE)) {
        /* if reception data register is not empty ,I2C1 will read a data from I2C_DATA */
        i2c_rxbuffer[i2c_rx_num] = i2c_data_receive(I2C1);
        i2c_rx_num++;

    } else if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_STPDET)) {

        //printf("get num == %d\r\n",i2c_rx_num);
        print_register_value(i2c_rxbuffer,i2c_rx_num);
        /* clear the STPDET bit */
        i2c_enable(I2C1);
        i2c_rx_num = 0;
        i2c_tx_num = 0;
        isfirst = 0;
    }
}


/*!
    \brief      handle I2C1 error interrupt request
    \param[in]  none
    \param[out] none
    \retval     none
*/
void I2C1_ErrorIRQ_Handler(void)
{
    /* no acknowledge received */
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_AERR)) {
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_AERR);
    }

    /* SMBus alert */
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_SMBALT)) {
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_SMBALT);
    }

    /* bus timeout in SMBus mode */
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_SMBTO)) {
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_SMBTO);
    }

    /* over-run or under-run when SCL stretch is disabled */
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_OUERR)) {
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_OUERR);
    }

    /* arbitration lost */
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_LOSTARB)) {
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_LOSTARB);
    }

    /* bus error */
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_BERR)) {
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_BERR);
    }

    /* CRC value doesn't match */
    if(i2c_interrupt_flag_get(I2C1, I2C_INT_FLAG_PECERR)) {
        i2c_interrupt_flag_clear(I2C1, I2C_INT_FLAG_PECERR);
    }
    // /* disable the I2C1 interrupt */
    // i2c_interrupt_disable(I2C1, I2C_INT_ERR);
    // i2c_interrupt_disable(I2C1, I2C_INT_BUF);
    // i2c_interrupt_disable(I2C1, I2C_INT_EV);
}

6、现象，
树莓派发送数据：i2ctransfer -f -y 1 w4@0x18 0x08 0x09 0xA0 0xA3
gd32打印
在这里插入图片描述
树莓派读取数据：
i2ctransfer -y -f 1 w3@0x30 0x18 0x19 0x56 r3
发送三个数据读取三个，gd32打印如下：

树莓派读取的数据：

0x98 0x78 0x67是我们定义的数据
volatile uint8_t i2c_txbuffer[4] = {0x98,0x78,0x67,0xff};
7、代码路径：https://gitee.com/xiaoguo-tec_0/gd32-iap-code.git