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@herzig
Created August 9, 2019 10:12
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esp32 i2c scan (esp-idf)
// 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;
i2c_param_config(I2C_NUM_0, &conf);
return i2c_driver_install(I2C_NUM_0, conf.mode, 0, 0, 0);
}
void app_main()
{
// i2c init & scan
if (i2c_master_init() != ESP_OK)
ESP_LOGE(TAG, "i2c init failed\n");
printf("i2c scan: \n");
for (uint8_t i = 1; i < 127; i++)
{
int ret;
i2c_cmd_handle_t cmd = i2c_cmd_link_create();
i2c_master_start(cmd);
i2c_master_write_byte(cmd, (i << 1) | I2C_MASTER_WRITE, 1);
i2c_master_stop(cmd);
ret = i2c_master_cmd_begin(I2C_NUM_0, cmd, 100 / portTICK_RATE_MS);
i2c_cmd_link_delete(cmd);
if (ret == ESP_OK)
{
printf("Found device at: 0x%2x\n", i);
}
}
}
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