yes, I already played with the USB cable. Some basically not work at all, I cannot even upload the code runs into "MD5 of file does not match data in flash!" error. I have long and short one that works, at least I can upload the code.
But, I was trying I think hundred time to upload the code and check in the serial monitor. Never worked but ONE time not long before. After I uploaded I realized the led is blinking in blue. And the serial monitor also shows the hello world. See attached
After this I tried to upload the code again and not works any more. Again tried hundred times. Pushing the reset button then EN and whatever combination. I was wondering I might pushed the buttons in a combiantion that I have not before. But not works....I am really fed up.
By the way my code is uploaded without pushing the reset (IOO) button during "Connecting". Does that mean that my board can manage it through the software?
Iintentianally I did not buy an old one. This was 25 EUR and bought from a domestic seller not even oredered from China. But of course this still can be a bad one too, does not matter where I bought.