Blank printer firmware

I appeal, first of all, to the site moderators.

I downloaded an updated version of arduino-1.8.9 with the goal of writing a firmware for Prusia.

I wanted to update my printer firmware, hoping to use the new options arduino-1.8.9

In the new firmware, as before, I wanted to see the Marlin.ino file in an environment with many other files -
as a starting file, for writing my firmware.

As a result of the download, I found a completely empty file (without many bookmarks like "configuration.h")

I went to the Arduino site and found that I needed to establish a connection with the printer by choosing the right
COM3 port and data rates of 250000.

I installed it all.

Further instructions on the site called me to press the "Apload" button. At this moment, I did not have a firmware written by me,
I just wanted to do this, and I could not guess that with this action I would load onto my printer,
absolutely empty firmware, and destroy the firmware that was on my printer.

I really want to swear strongly !!! Now my printer does not respond to anything and its screen shows me cubes.
and turned into nothing.

Tell me, in great detail, how to make an O-em printer firmware that has nothing in memory.

I beg you, this is very important to me.

Make a correction on the site, so that people do not fall into this situation.


Don't jump into unrelated posts please as it is considered bad.
Your email was also removed to prevent SPAM.

When you upload a blank sketch it will over write the original and you can use the same process to write a new firmware onto the board.

Can your computer still see the board and COM port ?