esp_rom_spiflash_erase_sector() function
Erase a sector of flash. Uses SPI flash command 20H. Please do not call this function in SDK.
Return value
ESP_ROM_SPIFLASH_RESULT_OK : Erase OK. ESP_ROM_SPIFLASH_RESULT_ERR : Erase error. ESP_ROM_SPIFLASH_RESULT_TIMEOUT : Erase timeout.