Welcome to today's blog post. Today we would like to answer a frequently asked question from our support department: how can I reflash the bootloader on the Nano?
Microcontrollers like the NanoV3 are shipped with a bootloader already installed. This allows you to write programs to the module via the Arduino IDE.
So if the module does not work anymore it can be because the bootloader is faulty. Also this method allows to flash modules with the original bootloader up to date, so you don't have to select "old bootloader" at "processor" every time.
To reprogram the chip we need a programming device. There are special programmers for this, but most of them already have a suitable solution in their drawer.
So today we show you how to make a programmer out of a microcontroller compatible with Arduino Uno R3, and how to supply a Nano with a new bootloader.
To do this, we connect the microcontroller to the PC, and start the ArduinoIDE. In the menu "File we go to "Examples" -> "11. ArduinoISP" -> "ArduinoISP".
Now we make sure that we have selected "Arduino/Genuino Uno" as board, and set the correct COM port, and load the sketch on our microcontroller, compatible with Arduino Uno R3.
Now we wire our Uno to our NanoV3 as shown in the picture:
It may be possible that you add a 10µm capacitor on the programming controller between GND(-) and RESET(+).
After we have connected everything properly, we need to make a few settings in the Arduino IDE so that we can flash the new bootloader to the Nano.
To do this, we go to "Tools" in the menu and select the "Arduino Nano" as the board. As Com-Port we leave the Uno selected and as Programmer we set "Arduino as ISP".
ATTENTION: the options ArduinoISP and ArduinoISP.org don't work, only the entry "Arduino as ISP".
After we have checked all settings again, we can start the flash process via the menu "Tools" using "Write Bootloader". After only a few moments the process is finished and our Nano V3 is ready for use again.