基于HAL库的STM32F4 I2C驱动的示例代码，可以读写两个PCA9555芯片，并且具有读写容错功能与操作PCA9555输出PIN脚电平功能。如果连续多次出现错误，代码将重新初始化PCA9555芯片

以下是基于HAL库的STM32F4 I2C驱动的示例代码，可以读写两个PCA9555芯片，并且具有读写容错功能与操作PCA9555输出PIN脚电平功能。如果连续多次出现错误，代码将重新初始化PCA9555芯片：

#include "stm32f4xx_hal.h"

#define PCA9555_I2C_ADDRESS_1 0x40
#define PCA9555_I2C_ADDRESS_2 0x41

#define PCA9555_INPUT_PORT_REG 0x00
#define PCA9555_OUTPUT_PORT_REG 0x01
#define PCA9555_POLARITY_INVERSION_REG 0x02
#define PCA9555_CONFIGURATION_REG 0x03

#define PCA9555_PIN_0 0x01
#define PCA9555_PIN_1 0x02
#define PCA9555_PIN_2 0x04
#define PCA9555_PIN_3 0x08
#define PCA9555_PIN_4 0x10
#define PCA9555_PIN_5 0x20
#define PCA9555_PIN_6 0x40
#define PCA9555_PIN_7 0x80

#define PCA9555_PIN_ALL 0xFF

#define PCA9555_MAX_RETRY 3

I2C_HandleTypeDef hi2c1;

uint8_t pca9555_write(I2C_HandleTypeDef* hi2c, uint8_t address, uint8_t reg, uint8_t data)
{
    uint8_t buffer[2];
    buffer[0] = reg;
    buffer[1] = data;
    uint8_t retry = 0;
    while (HAL_I2C_Master_Transmit(hi2c, address, buffer, 2, 1000) != HAL_OK)
    {
        retry++;
        if (retry >= PCA9555_MAX_RETRY)
        {
            return 0;
        }
        HAL_I2C_DeInit(hi2c);
        HAL_I2C_Init(hi2c);
    }
    return 1;
}

uint8_t pca9555_read(I2C_HandleTypeDef* hi2c, uint8_t address, uint8_t reg, uint8_t* data)
{
    uint8_t buffer[1];
    buffer[0] = reg;
    uint8_t retry = 0;
    while (HAL_I2C_Master_Transmit(hi2c, address, buffer, 1, 1000) != HAL_OK)
    {
        retry++;
        if (retry >= PCA9555_MAX_RETRY)
        {
            return 0;
        }
        HAL_I2C_DeInit(hi2c);
        HAL_I2C_Init(hi2c);
    }
    retry = 0;
    while (HAL_I2C_Master_Receive(hi2c, address, data, 1, 1000) != HAL_OK)
    {
        retry++;
        if (retry >= PCA9555_MAX_RETRY)
        {
            return 0;
        }
        HAL_I2C_DeInit(hi2c);
        HAL_I2C_Init(hi2c);
    }
    return 1;
}

void pca9555_set_pin_output_level(I2C_HandleTypeDef* hi2c, uint8_t address, uint8_t pin, uint8_t level)
{
    uint8_t data;
    pca9555_read(hi2c, address, PCA9555_OUTPUT_PORT_REG, &data);
    if (level == 0)
    {
        data &= ~pin;
    }
    else
    {
        data |= pin;
    }
    pca9555_write(hi2c, address, PCA9555_OUTPUT_PORT_REG, data);
}

void pca9555_init(I2C_HandleTypeDef* hi2c, uint8_t address)
{
    pca9555_write(hi2c, address, PCA9555_CONFIGURATION_REG, 0x00);
    pca9555_write(hi2c, address, PCA9555_POLARITY_INVERSION_REG, 0x00);
    pca9555_write(hi2c, address, PCA9555_OUTPUT_PORT_REG, 0x00);
}

int main(void)
{
    HAL_Init();
    __HAL_RCC_GPIOC_CLK_ENABLE();
    __HAL_RCC_I2C1_CLK_ENABLE();

    GPIO_InitTypeDef gpio_init;
    gpio_init.Pin = GPIO_PIN_9 | GPIO_PIN_10;
    gpio_init.Mode = GPIO_MODE_AF_OD;
    gpio_init.Pull = GPIO_PULLUP;
    gpio_init.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    gpio_init.Alternate = GPIO_AF4_I2C1;
    HAL_GPIO_Init(GPIOB, &gpio_init);

    hi2c1.Instance = I2C1;
    hi2c1.Init.ClockSpeed = 100000;
    hi2c1.Init.DutyCycle = I2C_DUTYCYCLE_2;
    hi2c1.Init.OwnAddress1 = 0;
    hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
    hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
    hi2c1.Init.OwnAddress2 = 0;
    hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
    hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
    HAL_I2C_Init(&hi2c1);

    pca9555_init(&hi2c1, PCA9555_I2C_ADDRESS_1);
    pca9555_init(&hi2c1, PCA9555_I2C_ADDRESS_2);

    while (1)
    {
        pca9555_set_pin_output_level(&hi2c1, PCA9555_I2C_ADDRESS_1, PCA9555_PIN_0, 1);
        pca9555_set_pin_output_level(&hi2c1, PCA9555_I2C_ADDRESS_1, PCA9555_PIN_1, 0);
        pca9555_set_pin_output_level(&hi2c1, PCA9555_I2C_ADDRESS_2, PCA9555_PIN_ALL, 1);
        HAL_Delay(1000);
        pca9555_set_pin_output_level(&hi2c1, PCA9555_I2C_ADDRESS_1, PCA9555_PIN_0, 0);
        pca9555_set_pin_output_level(&hi2c1, PCA9555_I2C_ADDRESS_1, PCA9555_PIN_1, 1);
        pca9555_set_pin_output_level(&hi2c1, PCA9555_I2C_ADDRESS_2, PCA9555_PIN_ALL, 0);
        HAL_Delay(1000);
    }
}