Hello, Habr!
Recently I had such a situation: I bought an Arduino Leonardo, used it for a year. And suddenly it stopped working. I began to google hard, trying to figure out how to save the board. And I realized that there are not so many guides describing methods of salvation, so I decided to write my own.
So, we are given an Arduino board (it does not matter which one), into which the sketch is not loaded. What to do with it?
Check IDE settings.
Yes, yes, often the problem lies precisely in the wrong settings. Therefore, the first step is to check whether the correct port is selected, whether the correct board, programmer, bootloader, etc. is selected. Detailed instructions on setting up an IDE for almost any board can be Google, I will not list them all here.
Drivers.
Sometimes the problem lies in the lack of drivers for working with the board. If the board has a CH340 microcircuit, then you need to install a driver for it, and then everything will most likely work. You can find it, for example, here
Serial
If your board communicates with other programs on the computer (Putty, port monitor, etc.), then disconnect all programs from it, with a 90% probability everything will work.
Periphery
If in your project to pins RX and TX (meaning the 0th and 1st pins), then disconnect everything from them, otherwise the firmware will not be loaded
, . :
, 99,9% .
, Arduino Leonardo, . : 2. , , ( ), , 10 . RESET GND. .
!