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esp_flash_t* example_init_ext_flash(void)
{
  spi_bus_config_t bus_config = {
	.mosi_io_num = GPIO_NUM_12,
	.miso_io_num = GPIO_NUM_13,
	.sclk_io_num = GPIO_NUM_15,
	.quadwp_io_num = -1,
	.quadhd_io_num = -1
    };

    const esp_flash_spi_device_config_t device_config = {
        .host_id = SPI2_HOST,
        .cs_io_num = GPIO_NUM_5,
        .io_mode = SPI_FLASH_SLOWRD,
        .speed = ESP_FLASH_40MHZ,
        .input_delay_ns = 0,
        .cs_id = 0,
        .freq_mhz = 40,
    };

    ESP_LOGI(API_TAG_IO, "Initializing external SPI Module");
    ESP_LOGI(API_TAG_IO, "Pin assignments:");
    ESP_LOGI(API_TAG_IO, "MOSI: %2d   MISO: %2d   SCLK: %2d   CS: %2d",
        bus_config.mosi_io_num, bus_config.miso_io_num,
        bus_config.sclk_io_num, device_config.cs_io_num
    );

    // Initialize the SPI bus
    ESP_ERROR_CHECK(spi_bus_initialize(SPI2_HOST, &bus_config, SPI2_HOST));

    // Add device to the SPI bus
    esp_flash_t* ext_flash;
    ESP_ERROR_CHECK(spi_bus_add_flash_device(&ext_flash, &device_config));
	
    // Probe the Flash chip and initialize it
    // ERASE DOES NOT WORK WITH THIS
    ext_flash->chip_drv = &esp_flash_chip_winbond;
    esp_err_t err = esp_flash_init(ext_flash);
    if (err != ESP_OK) {
        ESP_LOGE(API_TAG_IO, "Failed to initialize external Flash: %s (0x%x)", esp_err_to_name(err), err);
        return NULL;
    }

    ext_flash->size = 32*1024*1024;
    esp_flash_set_chip_write_protect(ext_flash,false);

    return ext_flash;
}