Added documentation on flashing over serial with esptool

README.md

@@ -16,6 +16,7 @@ This is being developed in my free time as a fun project. It is no where near be
 ![](./.screens/preview1.png) ![](./.screens/preview2.png)
 
 # Flashing the Firmware
+###### Using VS Code
 1. Add your user to the `dialout` group: `sudo gpasswd -a YOURUSERNAME dialout` *(You will need to re-login after adding your user to the `dialout` group for it to take affect)*
 2. Install [Visual Studio Code](https://code.visualstudio.com/)
 3. Install the [PlatformIO plugin](https://platformio.org/install/ide?install=vscode)
@@ -23,7 +24,12 @@ This is being developed in my free time as a fun project. It is no where near be
 5. Press **F1** and select `PlatformIO: Build`
 6. Press **F1** and select `PlatformIO: Upload`
 
-**Note:** Your device will likely be `/dev/ttyAMC0` or `/dev/ttyUSB0`
+###### Using ESP Tool
+1. Take the `firmware.bin` file from the release page and download it. *(no releases yet, we still building)*
+2. Install [esptool](https://pypi.org/project/esptool/): `pip install esptool`
+3. Hold down the trackball on the device, turn it on, and plug it in to the computer.
+4. Confirm the serial device in your `/dev` directory *(Your device will likely be `/dev/ttyAMC0` or `/dev/ttyUSB0`)*
+5. Flash the device: `esptool.py --chip esp32 --port /dev/ttyUSB0 --baud 115200 write_flash -z 0x1000 firmware.bin`
 
 # Roapmap
 - [X] Wifi scanning & selection menu