When I buyed CORE modul and connect to PC, LED diode is on and Windows recognize new hardware… And all working well.
Now, I ordered 3 pcs CORE-NR
https://shop.bigclown.com/core-module-nr/
and after plug in to the PC it’s nothing… No LED lights, no hardware detection in Windows…
IS somewhere guide how to make it live?
If you buy only core modules ? Then no contains firmware. You must flash any firmware, use bcf tool, install is descprite here https://www.bigclown.com/doc/tutorials/playground-setup/
bcf update
bcf list
and
bcf flash --dfu …
Karel: Really? I hope some “blinky” is default firmware from production… It will be more user friendly if LED will be blinky after connection…
So, issue was in nonsoldered button “B” on CORE module and can’t switch module to DFU state and can’t recognized by Windows. After pin soldering it’s working well and CORE modul is recognized as STM32 BOOTLOADER device in USB devices.
I didn’t tried to switch to DFU another two modules before, only one with bad button… 
I don’t know if was problem from production or from my side, because this board was dropt from desk to ground :-/.