I immediatly flashed my sketch with the Arduino IDE, and this just worked.
Now I worked further on the sketch...and uploading isn't possible anymore, I always get
"esptool.FatalError: Failed to connect to ESP8266: Timed out waiting for packet header"
My guess is that because of the serial connection in the first sketch, it's busy now or so...no idea.
I tried connecting D3 (GPIO0) to ground forcing programming mode (BLUE LED is off wenn doing this), but with no succes. I also tried pressing reset in different ways.
I also installed the USB driver...
Has someone any tips what I could try?
Thanks a lot!