title: ESP8266: Timed out waiting for packet header
body: <p>Hi somebody who can link an beginners guide for ESP 8266 on arduino uno? Or help me with this error :</p>
  
  <blockquote>
    <p>Arduino:1.8.9 (Windows 10), Kort:"Generic ESP8266 Module, 80 MHz,
    Flash, Legacy (new can return nullptr), All SSL ciphers (most
    compatible), dtr (aka nodemcu), 26 MHz, 40MHz, DOUT (compatible), 4MB
    (FS:3MB OTA:~512KB), 2, nonos-sdk 2.2.1+100 (190703), v2 Lower Memory,
    Disabled, None, Only Sketch, 115200"</p>
    
    <p>Executable segment sizes:</p>
    
    <p>IROM   : 227372          - code in flash         (default or
    ICACHE_FLASH_ATTR) </p>
    
    <p>IRAM   : 26368   / 32768 - code in IRAM          (ICACHE_RAM_ATTR,
    ISRs...) </p>
    
    <p>DATA   : 1252  )         - initialized variables (global, static) in
    RAM/HEAP </p>
    
    <p>RODATA : 672   ) / 81920 - constants             (global, static) in
    RAM/HEAP </p>
    
    <p>BSS    : 24848 )         - zeroed variables      (global, static) in
    RAM/HEAP </p>
    
    <p>Sketch uses 255664 bytes (24%) of program storage space. Maximum is
    1044464 bytes. Global variables use 26772 bytes (32%) of dynamic
    memory, leaving 55148 bytes for local variables. Maximum is 81920
    bytes. esptool.py v2.8 Serial port COM3
    Connecting........_____....._____....._____....._____....._____....._____.....____Traceback (most recent call last):   File
    "C:\Users\Elev\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.6.3/tools/upload.py",
    line 65, in 
        esptool.main(cmdline)   File "C:/Users/Elev/AppData/Local/Arduino15/packages/esp8266/hardware/esp8266/2.6.3/tools/esptool\esptool.py",
    line 2890, in main
        esp.connect(args.before)   File "C:/Users/Elev/AppData/Local/Arduino15/packages/esp8266/hardware/esp8266/2.6.3/tools/esptool\esptool.py",
    line 483, in connect
        raise FatalError('Failed to connect to %s: %s' % (self.CHIP_NAME, last_error)) esptool.FatalError: Failed to connect to ESP8266: Timed
    out waiting for packet header esptool.FatalError: Failed to connect to
    ESP8266: Timed out waiting for packet header</p>
  </blockquote>
  
  <p>_</p>
  
  <p>This report would have more information with
  "Show verbose output during compilation"
  option enabled in File -> Preferences.</p>