How do I update firmware on Mbot cube current version is 6.2

I would like to update the firmware so I can use x3g files instead of s3g files. I can get all the way to the upload stage of the process where it tells me to press the reset button then hit upload. When I do it always tells me the process failed. Does anyone have any suggestions?

It can be done only with the help of programmer AVRISP mkII. But the process is not easy. I loaded the firmware 7.5.0 and the printer began to understand x3g files.

Hi, can you teach me how to update the firmware with an AVRISP Programmer? Total newb here who knows nothing. I tried to google but didn’t quite understand. Would be much appreciated if you could help or point me in the right direction.