bs_bcu_app/bsp/bsp_iic.c

#include "bsp_delay.h"
#include "drv_sys.h"
#include "bsp_iic.h"

/**
 * @brief       <EFBFBD><EFBFBD>ʼ<EFBFBD><EFBFBD>IIC
 * @param       <EFBFBD><EFBFBD>
 * @retval      <EFBFBD><EFBFBD>
 */
void iic_init(void)
{
    GPIO_InitTypeDef gpio_init_struct;

    IIC_SCL_GPIO_CLK_ENABLE();  /* SCL<43><4C><EFBFBD><EFBFBD>ʱ<EFBFBD><CAB1>ʹ<EFBFBD><CAB9> */
    IIC_SDA_GPIO_CLK_ENABLE();  /* SDA<44><41><EFBFBD><EFBFBD>ʱ<EFBFBD><CAB1>ʹ<EFBFBD><CAB9> */

    gpio_init_struct.Pin = IIC_SCL_GPIO_PIN;
    gpio_init_struct.Mode = GPIO_MODE_OUTPUT_PP;        /* <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
    gpio_init_struct.Pull = GPIO_PULLUP;                /* <20><><EFBFBD><EFBFBD> */
    gpio_init_struct.Speed = GPIO_SPEED_FREQ_VERY_HIGH; /* <20><><EFBFBD><EFBFBD> */
    HAL_GPIO_Init(IIC_SCL_GPIO_PORT, &gpio_init_struct);/* SCL */

    gpio_init_struct.Pin = IIC_SDA_GPIO_PIN;
    gpio_init_struct.Mode = GPIO_MODE_OUTPUT_OD;        /* <20><>©<EFBFBD><C2A9><EFBFBD><EFBFBD> */
    HAL_GPIO_Init(IIC_SDA_GPIO_PORT, &gpio_init_struct);/* SDA */
    /* SDA<44><41><EFBFBD><EFBFBD>ģʽ<C4A3><CABD><EFBFBD><EFBFBD>,<2C><>©<EFBFBD><C2A9><EFBFBD><EFBFBD>,<2C><><EFBFBD><EFBFBD>, <20><><EFBFBD><EFBFBD><EFBFBD>Ͳ<EFBFBD><CDB2><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>IO<49><4F><EFBFBD><EFBFBD><EFBFBD><EFBFBD>, <20><>©<EFBFBD><C2A9><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><CAB1>(=1), Ҳ<><D2B2><EFBFBD>Զ<EFBFBD>ȡ<EFBFBD>ⲿ<EFBFBD>źŵĸߵ͵<DFB5>ƽ */

    iic_stop();     /* ֹͣ<CDA3><D6B9><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>豸 */
}

/**
 * @brief       IIC<EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>,<EFBFBD><EFBFBD><EFBFBD>ڿ<EFBFBD><EFBFBD><EFBFBD>IIC<EFBFBD><EFBFBD>д<EFBFBD>ٶ<EFBFBD>
 * @param       <EFBFBD><EFBFBD>
 * @retval      <EFBFBD><EFBFBD>
 */
static void iic_delay(void)
{
    delay_us(2);    /* 2us<75><73><EFBFBD><EFBFBD>ʱ, <20><>д<EFBFBD>ٶ<EFBFBD><D9B6><EFBFBD>250Khz<68><7A><EFBFBD><EFBFBD> */
}

/**
 * @brief       <EFBFBD><EFBFBD><EFBFBD><EFBFBD>IIC<EFBFBD><EFBFBD>ʼ<EFBFBD>ź<EFBFBD>
 * @param       <EFBFBD><EFBFBD>
 * @retval      <EFBFBD><EFBFBD>
 */
void iic_start(void)
{
    IIC_SDA(1);
    IIC_SCL(1);
    iic_delay();
    IIC_SDA(0);     /* START<52>ź<EFBFBD>: <20><>SCLΪ<4C><CEAA>ʱ, SDA<44>Ӹ߱<D3B8><DFB1>ɵ<EFBFBD>, <20><>ʾ<EFBFBD><CABE>ʼ<EFBFBD>ź<EFBFBD> */
    iic_delay();
    IIC_SCL(0);     /* ǯסI2C<32><43><EFBFBD>ߣ<EFBFBD>׼<EFBFBD><D7BC><EFBFBD><EFBFBD><EFBFBD>ͻ<EFBFBD><CDBB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
    iic_delay();
}

/**
 * @brief       <EFBFBD><EFBFBD><EFBFBD><EFBFBD>IICֹͣ<EFBFBD>ź<EFBFBD>
 * @param       <EFBFBD><EFBFBD>
 * @retval      <EFBFBD><EFBFBD>
 */
void iic_stop(void)
{
    IIC_SDA(0);     /* STOP<4F>ź<EFBFBD>: <20><>SCLΪ<4C><CEAA>ʱ, SDA<44>ӵͱ<D3B5><CDB1>ɸ<EFBFBD>, <20><>ʾֹͣ<CDA3>ź<EFBFBD> */
    iic_delay();
    IIC_SCL(1);
    iic_delay();
    IIC_SDA(1);     /* <20><><EFBFBD><EFBFBD>I2C<32><43><EFBFBD>߽<EFBFBD><DFBD><EFBFBD><EFBFBD>ź<EFBFBD> */
    iic_delay();
}

/**
 * @brief       <EFBFBD>ȴ<EFBFBD>Ӧ<EFBFBD><EFBFBD><EFBFBD>źŵ<EFBFBD><EFBFBD><EFBFBD>
 * @param       <EFBFBD><EFBFBD>
 * @retval      1<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD>ʧ<EFBFBD><EFBFBD>
 *              0<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӧ<EFBFBD><EFBFBD><EFBFBD>ɹ<EFBFBD>
 */
uint8_t iic_wait_ack(void)
{
    uint8_t waittime = 0;
    uint8_t rack = 0;

    IIC_SDA(1);     /* <20><><EFBFBD><EFBFBD><EFBFBD>ͷ<EFBFBD>SDA<44><41>(<28><>ʱ<EFBFBD>ⲿ<EFBFBD><E2B2BF><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>SDA<44><41>) */
    iic_delay();
    IIC_SCL(1);     /* SCL=1, <20><>ʱ<EFBFBD>ӻ<EFBFBD><D3BB><EFBFBD><EFBFBD>Է<EFBFBD><D4B7><EFBFBD>ACK */
    iic_delay();

    while (IIC_READ_SDA)    /* <20>ȴ<EFBFBD>Ӧ<EFBFBD><D3A6> */
    {
        waittime++;

        if (waittime > 250)
        {
            iic_stop();
            rack = 1;
            break;
        }
    }

    IIC_SCL(0);     /* SCL=0, <20><><EFBFBD><EFBFBD>ACK<43><4B><EFBFBD><EFBFBD> */
    iic_delay();
    return rack;
}

/**
 * @brief       <EFBFBD><EFBFBD><EFBFBD><EFBFBD>ACKӦ<EFBFBD><EFBFBD>
 * @param       <EFBFBD><EFBFBD>
 * @retval      <EFBFBD><EFBFBD>
 */
void iic_ack(void)
{
    IIC_SDA(0);     /* SCL 0 -> 1 ʱ SDA = 0,<2C><>ʾӦ<CABE><D3A6> */
    iic_delay();
    IIC_SCL(1);     /* <20><><EFBFBD><EFBFBD>һ<EFBFBD><D2BB>ʱ<EFBFBD><CAB1> */
    iic_delay();
    IIC_SCL(0);
    iic_delay();
    IIC_SDA(1);     /* <20><><EFBFBD><EFBFBD><EFBFBD>ͷ<EFBFBD>SDA<44><41> */
    iic_delay();
}

/**
 * @brief       <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ACKӦ<EFBFBD><EFBFBD>
 * @param       <EFBFBD><EFBFBD>
 * @retval      <EFBFBD><EFBFBD>
 */
void iic_nack(void)
{
    IIC_SDA(1);     /* SCL 0 -> 1  ʱ SDA = 1,<2C><>ʾ<EFBFBD><CABE>Ӧ<EFBFBD><D3A6> */
    iic_delay();
    IIC_SCL(1);     /* <20><><EFBFBD><EFBFBD>һ<EFBFBD><D2BB>ʱ<EFBFBD><CAB1> */
    iic_delay();
    IIC_SCL(0);
    iic_delay();
}

/**
 * @brief       IIC<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD>ֽ<EFBFBD>
 * @param       data: Ҫ<EFBFBD><EFBFBD><EFBFBD>͵<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
 * @retval      <EFBFBD><EFBFBD>
 */
void iic_send_byte(uint8_t data)
{
    uint8_t t;
    
    for (t = 0; t < 8; t++)
    {
        IIC_SDA((data & 0x80) >> 7);    /* <20><>λ<EFBFBD>ȷ<EFBFBD><C8B7><EFBFBD> */
        iic_delay();
        IIC_SCL(1);
        iic_delay();
        IIC_SCL(0);
        data <<= 1;     /* <20><><EFBFBD><EFBFBD>1λ,<2C><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD>η<EFBFBD><CEB7><EFBFBD> */
    }
    IIC_SDA(1);         /* <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>, <20><><EFBFBD><EFBFBD><EFBFBD>ͷ<EFBFBD>SDA<44><41> */
}

/**
 * @brief       IIC<EFBFBD><EFBFBD>ȡһ<EFBFBD><EFBFBD><EFBFBD>ֽ<EFBFBD>
 * @param       ack:  ack=1ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ack; ack=0ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>nack
 * @retval      <EFBFBD><EFBFBD><EFBFBD>յ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
 */
uint8_t iic_read_byte(uint8_t ack)
{
    uint8_t i, receive = 0;

    for (i = 0; i < 8; i++ )    /* <20><><EFBFBD><EFBFBD>1<EFBFBD><31><EFBFBD>ֽ<EFBFBD><D6BD><EFBFBD><EFBFBD><EFBFBD> */
    {
        receive <<= 1;  /* <20><>λ<EFBFBD><CEBB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>,<2C><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>յ<EFBFBD><D5B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>λҪ<CEBB><D2AA><EFBFBD><EFBFBD> */
        IIC_SCL(1);
        iic_delay();

        if (IIC_READ_SDA)
        {
            receive++;
        }
        
        IIC_SCL(0);
        iic_delay();
    }

    if (!ack)
    {
        iic_nack();     /* <20><><EFBFBD><EFBFBD>nACK */
    }
    else
    {
        iic_ack();      /* <20><><EFBFBD><EFBFBD>ACK */
    }

    return receive;
}