Unable to upload Sketch to esp8266-01 cannot connect to the board


I have successfully flashed a the firmware to the esp8266-01 board that i have it connected breadboard and using uno to communicate with it.

Here is how i connected it while i was flashing the firmware.

ESP8266:____________ Arduino:

GND -------------------------- GND

GP2 -------------------------- Not connected (open)

GP0 -------------------------- GND

RXD -------------------------- RX

TXD -------------------------- TX

CHPD ------------------------ 3.3V

RST -------------------------- Not connected (open)

VCC -------------------------- 3.3V
REST ........... GND

I got the firmware from here and the software from here

Let me know if i flashed the correct firmware.

Now i have installed the esp8266 library from a third part URL and selected the Generic ESP8266 module and baud rate 115200, when i try to upload a test sketch it cant connect to the board.

Here is the skecth that i am trying to upload

void setup()

void loop()
  Serial.write("Hello From -01");

Here is the error i am getting

Executable segment sizes:

IROM   : 231780          - code in flash         (default or ICACHE_FLASH_ATTR) 

IRAM   : 26908   / 32768 - code in IRAM          (ICACHE_RAM_ATTR, ISRs...) 

DATA   : 1252  )         - initialized variables (global, static) in RAM/HEAP 

RODATA : 704   ) / 81920 - constants             (global, static) in RAM/HEAP 

BSS    : 24936 )         - zeroed variables      (global, static) in RAM/HEAP 

Sketch uses 260644 bytes (27%) of program storage space. Maximum is 958448 bytes.
Global variables use 26892 bytes (32%) of dynamic memory, leaving 55028 bytes for local variables. Maximum is 81920 bytes.
esptool.py v2.8
Serial port COM4
Connecting........_____....._____....._____....._____....._____....._____.....____Traceback (most recent call last):
  File "C:\Users\Vasim\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.6.3/tools/upload.py", line 65, in <module>
  File "C:/Users/Vasim/AppData/Local/Arduino15/packages/esp8266/hardware/esp8266/2.6.3/tools/esptool\esptool.py", line 2890, in main
  File "C:/Users/Vasim/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: Invalid head of packet (0xF0)
the selected serial port _
 does not exist or your board is not connected

Edit: I disconnected the GPIO0 from the ground after i was done flashing the firmware to upload the sketch. I also tried swamping the RX/TX pins

You ESP-01 is not on COM4.

You ESP-01 is not on COM4.

Thanks for replying,

I have double checked there are no additional ports other then COM4, i have connected the RESET of Arduino to the GND mentioned above that should bypass the atmega microcontroller right ? and let me communicate with esp-01 right ?.

When i connect the arduino with the usb the esp-01 blue led flickers for a second and goes off, while trying to upload the led doesn't turn on at all, tho the module does stay warm.

Are you sure that i have flashed the correct firmware ?