tx pinout switch, 8266 uploading warning: espcomm_sync failed error: espcomm_ope

Projects Programming
1 
change tx pin to gpio ,,, i solve this problem with ota upload

void setup() {
  Serial.begin(9600);
  while (!Serial);
WiFi.hostname("xxxxx");      // DHCP Hostname (useful for finding device for static lease)
  ArduinoOTA.setHostname("xxxx");
  ArduinoOTA.setPort(8266);
  ArduinoOTA.setPassword("");
  ArduinoOTA.onStart([]() {

    /////////////////change pin to gpio////////
    //GPIO 1 (TX) swap the pin to a GPIO.
    pinMode(1, FUNCTION_3);
    //GPIO 3 (RX) swap the pin to a GPIO.
    pinMode(3, FUNCTION_3);
    ///////////////////////
    String type;
    if (ArduinoOTA.getCommand() == U_FLASH) {
      type = "sketch";
    } else { // U_SPIFFS
      type = "filesystem";
    }

    // NOTE: if updating SPIFFS this would be the place to unmount SPIFFS using SPIFFS.end()
    Serial.println("Start updating " + type);
  });
  ArduinoOTA.onEnd([]() {
    ////////////////change pin to rx tx again//////////
    //GPIO 1 (TX) swap the pin to a TX.
    pinMode(1, FUNCTION_0);
    //GPIO 3 (RX) swap the pin to a RX.
    pinMode(3, FUNCTION_0);
    ///////////////////////
    Serial.println("\nEnd");
  });
  ArduinoOTA.begin();
  delay(1000);
}