herzig

// setup i2c master
static esp_err_t i2c_master_init()
{
    i2c_config_t conf;
    conf.mode = I2C_MODE_MASTER;
    conf.sda_io_num = I2C_SDA_PIN;
    conf.scl_io_num = I2C_SCL_PIN;
    conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
    conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
    conf.master.clk_speed = I2C_MASTER_FREQ_HZ;