Flash Bootloader – Classic

Some Signs a bootloader might be corrupt, or incorrect:

  • FC does not appear as Arduino Leonardo under a com port.
  • FC appears in device manager but with a yellow exclamation point.
  • When plugging in the FC you are warned about a missing device descriptor.
  • Computer doesn’t detect the FC at all.

How to Flash a Bootloader using a USBasp

This process assumes Arduino Software is installed, you have a soldering iron, header pins, and  a USBasp along with a Micro JST 1.0mm 6 pin connector – Sparkfun or eBay for the classic or a Micro JST 1.5mm 6 pin connector – eBay for the narrow. For Windows, you may also need the USBasp drivers.

1.) Connect/solder the wires from the Micro JST 1.0 6 pin connector to the SPI, matching the pinout as shown.

USBasp pinout
USBasp pinout
alienflight SPI Pinout
alienflight SPI Pinout

2.) Plug the USBasp into your computer

USBasp connected
USBasp connected

3.) Launch Arduino, and navigate to Tools >Board and select Arduino Leonardo choose arduino leonardo board

4.) Navigate to Tools > Programmer, and select USBasp

Arduino Programmer USBasp
Arduino Programmer USBasp

5.) Navigate to Tools again, and select Burn Bootloader

Burn Bootloader
Burn Bootloader

You’ll be presented with a message at the bottom of the Arduino window stating “Burning Bootloader to I/O Board (this may take a minute)“. During this time notice that both data LEDS on the USBasp are solid.

Once Arduino is finished, there should be a message stating “Done Burning Bootloader“.

6.) At this point your board should have a compatible bootloader, and you can proceed to Install a Sketch.