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/**
 * @brief Read from I2C device
 *
 * @note The LP I2C must have been initialized from the HP core using the lp_core_i2c_master_init() API
 * before invoking this API.
 *
 * @param lp_i2c_num    LP I2C port number
 * @param device_addr   I2C device address (7-bit)
 * @param data_rd       Buffer to hold data to be read
 * @param size          Size of data to be read in bytes
 * @param timeout       Operation timeout in CPU cycles. Set to -1 to wait forever.
 *
 * @return esp_err_t    ESP_OK when successful
 *
 * @note the LP I2C does not support 10-bit I2C device addresses.
 * @note the LP I2C port number is ignored at the moment.
 */
esp_err_t lp_core_i2c_master_read_from_device(i2c_port_t lp_i2c_num, uint16_t device_addr,
                                            uint8_t *data_rs, size_t size,
                                            int32_t ticks_to_wait);

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uint8_t data_rd[2];
    esp_err_t ret = lp_core_i2c_master_read_from_device(LP_I2C_NUM_0, BH1750_I2C_ADDR, data_rd, sizeof(data_rd), LP_I2C_TRANS_TIMEOUT_CYCLES);
    if (ret != ESP_OK) {
        // Skip this round of calculation and return
        return;
    }

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#define BH1750_I2C_ADDR                 0x23

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esp_err_t lp_core_i2c_master_write_to_device(i2c_port_t lp_i2c_num, uint16_t device_addr,
                                            const uint8_t *data_wr, size_t size,
                                            int32_t ticks_to_wait)

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uint8_t data_wr[3];
data_wr[0] = (uint8_t) reg_addr;  //寄存器地址
data_wr[1] = (uint8_t) (reg_date>> 8);
data_wr[2] = (uint8_t) reg_date;

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esp_err_t lp_core_i2c_master_write_to_device(i2c_port_t lp_i2c_num, uint16_t device_addr,
                                            const uint8_t *data_wr, size_t size,
                                            int32_t ticks_to_wait)

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esp_err_t lp_core_i2c_master_read_from_device(i2c_port_t lp_i2c_num, uint16_t device_addr,
                                            uint8_t *data_rd, size_t size,
                                            int32_t ticks_to_wait)

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uint8_t data_wr = reg_addr;
uint8_t data_rd[2];