File "C:/Users/erics/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
I already used this board to put other codes, but when I switched to the protoboard I can't send any more codes.
Note: the built in led is always on, it does not turn off or when pressing the reset button